ISSUE 86 | SPRING 2017

Tier 3 regulations and their impact on refineries Best practices for using simulation models in FCC catalyst bids New catalyst, Ketjenfine® 780 STARS®, leads the way for clean fuels hydrotreating

ALBEMARLE CATALYST COURIER ISSUE 86 1 INSIDE THIS ISSUE… 4 NEWS FROM ALBEMARLE 6 HELPING REFINERS DRIVE DOWN SULFUR CONTENT 10 HELP WITH OPTIMIZING YOUR REFINERY OPERATIONS 14 OPTIMIZING VENDORS’ BIDS 18 SMOOTHFLOW™: CIRCULATION CURE-ALL 20 KETJENFINE® (KF) 780 STARS®: AN INTELLIGENT OPTION FOR FCC PRETREATMENT (FCC-PT) APPLICATIONS

Managing editor EVENTS DIARY 2017 Brooke Robertson E: [email protected] March Correspondence and distribution for Catalyst Courier 19–21 AFPM Annual Meeting, San Antonio, TX, USA Brooke Robertson 29–30 ARTC 20th Annual Meeting, Jakarta, Indonesia Albemarle Corporation 4350 Congress Street, Suite 700, Charlotte, NC 28209, USA www.albemarle.com September E: [email protected]

18–19 5th Refining India Conference, New Delhi, India For North and South America, contact: 18–20 Abu Dhabi International Downstream, Abu Dhabi, UAE Albemarle Corporation T: +1 281 480 4747 E: [email protected] October For Europe, the Middle East, CIS and the Indian subcontinent, contact: 2–4 AFPM Operations & Process Technology Summit Albemarle BV (formerly Q&A), Austin, TX, USA T: +31 20 6347300 E: [email protected]

For Asia Pacific, contact: Albemarle Chemicals (Shanghai) Co., Ltd T: +86 21 6103 8666 E: [email protected]

The information presented herein is believed to be accurate and reliable but is presented without guarantee or responsibility on the part of Albemarle Corporation and its subsidiaries. It is the responsibility of the user to comply with all applicable laws and regulations and to provide for a safe workplace. The user should consider any health or safety hazards or other information contained herein only as a guide, and should take those precautions which are necessary or prudent to instruct employees and to develop work practice procedures in order to promote a safe work environment. Further, nothing contained herein shall be taken as an inducement or recommendation to manufacture or use any of the herein materials or processes in violation of existing or future patent. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the copyright owner.

Copyright Albemarle Corporation, 2017 2 ALBEMARLE CATALYST COURIER ISSUE 86 SILVIO GHYOOT PRESIDENT, REFINING SOLUTIONS

THE CASE FOR CAUTIOUS OPTIMISM IN UNCERTAIN TIMES The past few years have seen a significant supply–demand imbalance in the oil and gas industry and a dramatic fall in oil prices associated with slowing economic growth. The refinery sector could do with a period of increased stability and predictability, but is that what the future holds?

Three main factors are driving the market for refinery catalysts: global megatrends such as rising populations and increased personal mobility; the continuing emphasis on environmental protection and more-stringent fuel specifications; and an industry-wide shift towards larger and more-complex refinery and petrochemical facilities.

The adoption of more-stringent limits for fuel emissions is a crucial issue in the hydroprocessing arena. In many parts of the world, the 10-ppm level for sulfur has become the norm and western environmental standards are being taken up more widely. There are changes too in FCC, which has long been a crucial part of the gasoline economy but is now making a larger contribution to petrochemicals and olefins.

Regional differences, price changes and greater crude complexity Future demand and the prospects for long-term growth center on emerging markets such as South East Asia, the Middle East and China. The situation will be very different across the West, where a continuing shift to alternative energy sources and improving fuel efficiency will be the controlling factors.

Oil prices clearly influence refinery margins. We think that oil will remain at its current range in 2017 and that we will see slight growth, but any sudden price change would be disruptive because it will cause uncertainty. Another challenge for refiners is how to convert more-complex crudes into ever-more-tightly specified products.

The outlook for 2017 suggests that refiners should be cautiously optimistic. We expect gasoline to grow, though not as much as it did from 2015 to 2016 when the market was in recovery. As the industry moves through another period of transition, Albemarle’s top priority is to provide customized products that help refiners to address current requirements, deliver products to specification and adapt to what could be an unpredictable future.

SILVIO GHYOOT PRESIDENT, REFINING SOLUTIONS

ALBEMARLE CATALYST COURIER ISSUE 86 3 NEWS FROM ALBEMARLE

LITHIUM OPERATIONS TO Atacama Desert, Chile EXPAND IN CHILE

After discussions with the Chilean de Atacama is the best lithium John Mitchell, president of Economic Development Agency brine reserve in the world and we Albemarle’s Lithium and Advanced and with legal approval from the have a responsibility to ensure this Materials Global Business Unit, appropriate authorities, Albemarle’s strategically important resource adds, “We are proud to be part of lithium production rights agreement is properly managed so that it can this transformational agreement in Chile has been amended. continue to provide value for all that allows for broad collaboration, stakeholders.” value sharing and sustainable The ideal place to support the development of important lithium- growing global demand for lithium, Albemarle’s Planta La Negra in based advanced materials within the the Atacama Desert holds enough Antofagasta will expand and its quota country of Chile.” lithium to supply the world for for authorized lithium extraction at the decades. However, this strategic Salar de Atacama facility will increase. The extended agreement also mineral is subject to strict extraction Effective from December 30, 2016, supports links between Albemarle quotas from the Chilean government. the amended agreement provides and the local indigenous communities Albemarle with sufficient lithium to while creating significant funding Stephen Elgueta, vice president produce more than 80,000 t/y of for research and development for of Albemarle’s lithium resources technical- and battery-grade lithium energy storage, renewable energy and group, says, “We believe the Salar salts over the next 27 years. advanced battery materials.

CMO FAREWELL TO CHEMETALL CMO AWARDAWARD CMO SURFACE TREATMENT WINNER AWARD

The $3.2 billion sale of Albemarle’s Chemetall surface treatment business Our Fine Chemistry Services and related assets to German chemicals group BASF is complete. group was a multi-category winner in the 2017 CMO Leadership Awards. The team Luke Kissam, Albemarle’s chairman, and refinery catalysts businesses. We won awards in all six of the core categories: president and chief executive officer, appreciate the contribution that the quality, reliability, capabilities, expertise, comments, “We are very pleased Chemetall surface treatment team has compatibility and development. to complete this transaction, which made to Albemarle over the last two will accelerate our transformation years and we are certain that BASF Life Science Leader developed the CMO into a company focused on powering will be an excellent steward of this Leadership Awards in 2011 to support the increased energy efficiency around outstanding business.” vetting of outsourcing partners, which is the world through our leading lithium a time-consuming and complex process. The winning contract manufacturing We are proud to be part of this transformational organizations (CMO) are chosen through agreement that allows for broad collaboration, value third-party, impartial market research based sharing and sustainable development of important lithium- on feedback from sponsor companies that utilize outsourcing services, so, very well based advanced materials within the country of Chile. done to the Fine Chemistry Services team.

4 ALBEMARLE CATALYST COURIER ISSUE 86 CORPORATE FOCUS As Albemarle continues to grow, we must not forget our responsibility to the environment. Here is a sample of the initiatives we follow.

Our marshes As a member of the American Chemistry EPA ENERGY STAR® partner We help to protect the environment Council, Albemarle is committed to ENERGY STAR is a voluntary program through two unique wastewater achieving the principles of Responsible run by the United States Environmental treatment facilities at our Magnolia, Care, including minimizing the footprint Protection Agency (EPA) that helps USA, plants. The marshes at the south from its operations; distributing products businesses and individuals to save money and west plants remove low levels of safely; providing excellent training; and protect the climate through superior toxic chemicals from large quantities auditing its carriers and distributors; energy efficiency. Albemarle is a partner of water using aquatic plants. Treating understanding and communicating the in ENERGY STAR and is committed to an average of one million gallons a day hazards of its products though testing; protecting the environment through of noncontact water and storm-water and being responsible contributors to the continuous improvement of its energy runoff, the project is a result of 20 years communities where it operates. performance. We believe that an of research by National Aeronautics and organization-wide energy management Space Administration on wastewater Corporate responsibility approach helps us to enhance our treatment and reuse in space. Our Pasadena, USA, plant has adopted financial health and to preserve the Jackson Intermediate School as a partner environment for future generations. Albemarle employees are on daily duty at in education. Albemarle employees the marshes where their responsibilities participate in book drives, science fair include feeding wildlife and monitoring judging, monthly mentoring programs the health of the marshes. and tutoring algebra and environment As a member of the education workshops. We also have American Chemistry Responsible Care employees serving on the education Council, Albemarle is Responsible Care is the US chemical subcommittee and the community industry’s award-winning performance relations and environment committees. committed to achieving initiative. It has resulted in a 70% the principles of reduction in emissions and an employee Our employees also partake in volunteer Responsible Care. safety record that is four times opportunities such blood drives and better than the average in the US the Trash Bash and Hazardous Waste manufacturing sector. Collection Day.

LUKE KISSAM ELECTED CHAIRMAN

On November 7, 2016, Luke Kissam succeeded Jim Nokes, who Kissam was elected as Albemarle’s continues to serve on the board of chairman in addition to his other directors as lead independent director. responsibilities. Kissam became Nokes commented, “It has been my chief executive officer in 2011, joined honor to serve as chairman of the board the board of directors in 2011 and of directors. I am confident in Luke’s became president in 2013. ability to lead this board, as he can help ensure leadership continuity through Albemarle’s continued growth.”

ALBEMARLE CATALYST COURIER ISSUE 86 5 HELPING REFINERS DRIVE DOWN SULFUR CONTENT

Striking the balance between investment costs, sustainability of operations and long-term profit DAVE CLARY VICE PRESIDENT, HEAVY OIL UPGRADING

The United States According to the EPA, the new gasoline and Europe as models for achieving sulfur standard will make emission the 10-ppm annual sulfur average, but Environmental control systems more effective for the configurations and capacities of Protection Agency (EPA) existing and new vehicles, and will enable oil refineries in these regions are often the application of more stringent vehicle very different from those in the USA. Tier 3 regulations came emissions standards, as removing sulfur Any comparison must acknowledge into force on January 1, enables a vehicle’s tailpipe catalytic the fact that US refiners have made converter to work more efficiently. major investments in infrastructure to 2017. These rules, The EPA estimates suggest that the maximize gasoline production from the which are designed to new sulfur standard will increase fuel refining of heavy sour crude oil. This oil manufacturers’ production costs by can be sourced from foreign markets at a reduce air pollution about 0.65¢ per gallon. significant discount compared with sweeter from passenger cars and crudes. Switching to sweeter feedstocks Small refining companies and low- might carry substantial cost implications trucks, require most volume refineries have more time to and, although it would help to ensure US refiners to reduce comply with the 10-ppm annual sulfur compliance, it would probably be no more average. Refiners that meet a range of than a short-term solution. the average level of criteria, including having fewer than sulfur in gasoline from 1500 employees company-wide and The challenge is to strike the right balance having produced less than 155,000 bbl between investment costs, sustainability of 30 to 10 ppmw, with a per calendar day during 2012, will have operations and long-term profit under the maximum of 80 ppmw until January 1, 2020, to comply. The EPA constraints of the Tier 3 regulations. This has also defined provisions that allow balance varies from refinery to refinery sulfur in any gallon of some companies to petition for delayed and may change over time as feedstocks, gasoline. compliance on a case-by-case basis for processes, catalysts and regulations evolve. situations of extreme hardship or extreme There is a further dimension to the issue of unforeseen circumstances. compliance. Although gasoline regulation changes generally focus on product sulfur, But, for most US refinery operators, they also affect octane quality. the new targets are an immediate and significant challenge. Some industry Focusing on FCC for sulfur removal commentators are looking to Japan The reformer and the FCC unit are the

6 ALBEMARLE CATALYST COURIER ISSUE 86 THOUGHT LEADER

biggest contributors of volume to the periods being required for planning, The main options include overall gasoline pool (Table 1), and FCC construction and commissioning. This ƒƒ more severe hydrotreating of the FCC gasoline is, by far, the biggest source is particularly true when the proposed feed of gasoline pool sulfur. Consequently, modifications require air permits or shift ƒƒ hydrotreating of FCC gasoline naphtha hydrotreating before the the focus toward more-expensive sweet ƒƒ undercutting heavy naphtha, which reformer, FCC pretreatment (FCC-PT) and crude sources rather than continuing contains a disproportionate amount FCC naphtha post-treatment have the with the conventional FCC approach to of sulfur, from the FCC unit into the most significant impacts on gasoline pool maximizing gasoline production. distillate pool sulfur. It seems likely that FCC-PT and FCC ƒƒ using fuel-sulfur reduction additives in naphtha post-treatment will be the main Complying with the Tier 3 regulations the FCC focuses when seeking to comply with and achieving the 10-ppm annual sulfur ƒƒ increasing the fraction of the gasoline Tier 3 gasoline regulations. Isomerization average will not be a simple task. Refinery pool coming from other units, for and alkylation are, by comparison, minor operators will have to adjust their example, alkylate and reformate processes in terms of their volume operating strategies and, in some cases, ƒƒ mercaptan removal from light contributions to the overall gasoline pool, commit to capital investments for new or gasoline. but they essentially produce sulfur-free, upgraded process equipment. high-octane gasoline components.

FCC gasoline accounts for 35–40% TYPICAL of the US gasoline pool and averages PROPORTION OF CONTRIBUTION 60–80 ppmw sulfur, with the exact value SULFUR, PPM GASOLINE POOL, % TO SULFUR, % depending on the sulfur content of the FULL-RANGE FCC NAPHTHA1 2000 45 99 feedstock. Consequently, significant LIGHT STRAIGHT-RUN NAPHTHA 150 3 <1 reductions in sulfur content will be BUTANES 10 5 «1 required to meet Tier 3 regulations. ALKYLATE 3 10 «1 For US refineries where the existing REFORMATE 1 32 «1 infrastructure is insufficient to deliver C5/C6 ISOMERATE 3 5 «1 the 10-ppm annual average, capital 1Range can be 300–3000 ppm sulfur, depending on the crude source and degree of investments may be required to achieve FCC feed hydrotreating compliance. Modifying facilities can be a time-intensive process with extended Table 1: Typical gasoline pool blending components. >>>

ALBEMARLE CATALYST COURIER ISSUE 86 7 >>> 10,000 to assess the likely impact of Tier 3 gasoline by up to 35%, but this will depend regulations. For refineries without FCC on the specifics of the refinery’s operations. 1,200–1,800 FCC feed naphtha post-treatment, the effects will be substantial. These companies will have to 1,000 Hydrotreating the FCC gasoline 40–600 shorten their cycles and increase hydrogen Refiners may need to hydrotreat their consumption at start of run. For constant FCC gasoline or increase the severity of HDS mode, refiners could face a 20–40% 60–100 existing hydrotreatment units to meet the 100 cycle length reduction if they continue to new requirements. An unfortunate side 20–35 rely on the same feeds. effect of this operation is the reduction in FCC naphtha gasoline octane due to olefin saturation. Tier 3 will also lead to higher annualized 10 This octane reduction adds to the value Tier 2 Tier 3 catalyst costs and make the integration of alkylate, which is both high octane and of FCC-PT–FCC unit turnarounds more low in sulfur, and so increases the need Figure 1: The transition from Tier 2 to complicated. Selecting higher activity for C4 streams with high olefinicity to feed Tier 3 in terms of sulfur content. catalysts could help to extend cycle the alkylation unit. lengths, as could switching to easier feeds. These possible solutions offer a range of Catalysts such as ACTION® from Albemarle Added cost will come in the form of new potential advantages and disadvantages. offer octane relief for refiners by increasing refining equipment or higher severity The option chosen will depend on factors the FCC gasoline octane and the production hydrotreating of gasoline. Additionally, the such as capital costs and specific operating and olefinicity of butylene from the FCC lower sulfur requirements will also cause constraints. unit, thereby enabling increased production refiners to blend less light naphtha into of high-octane, low-sulfur alkylate. the gasoline pool owing to its low sulfur Complying with Tier 3 and octane values. As companies look A recently published joint paper with

specifications for new ways to improve octane quality Marathon Petroleum discussed how the FCC Under the Tier 2 regulations, the FCC while meeting sulfur regulations, catalyst unit at the Galveston Bay refinery switched naphtha values were generally in the drop-in solutions for existing selective to Albemarle’s ACTION technology.1 The range 60 to 100 ppmw sulfur and the HDS gasoline units are effective ways for benefits went straight to the bottom FCC-PT hydrodesulfurization (HDS) them to capitalize on the market changes line. After data normalization using requirement was 90–95%. For Tier 3, the without large capital investments. KBC’s powerful FCC SIM kinetic model FCC naphtha values will be 20–35 ppmw to adjust for feed and operating changes, sulfur and the FCC-PT HDS requirement More severe hydrotreating of ACTION catalyst was shown to deliver will be over 97% (Figure 1). the FCC feed a 2.3 vol% increase in butylene yield, a Hydrotreating the FCC feed is an butylene olefinicity increase of more than The change to Tier 3 gasoline attractive option because it provides an 4% and an incremental improvement specifications will result in a slight effective way to remove sulfur (typically in product octane. These benefits, increase in operating stress for FCC lowering FCC feed sulfur content by combined with higher conversion, volume naphtha post-treatment units and a more 70–90%) and delivers other substantial gain improvement and better bottoms significant stress on FCC-PT units that benefits: greatly improved yields from the upgrading, resulted in a benefit of $1.60/bbl. lack any post-treatment capabilities. FCC unit with a relatively small negative impact on octane. This is probably the Tight oils have displaced conventional A key role for catalysis best long-term answer for refineries, Catalyst choices will play a crucial crudes in many cases and this trend is though it may require substantial lead role in the drive towards compliance, expected to continue. Tight oil (also known time to introduce and some operators particularly new-generation catalysts as shale oil or light tight oil) is a light may be reluctant if significant new capital for PT and hydrotreating processes. crude oil produced from low-permeability were to be required. Where feasible, the Albemarle offers solutions for refiners formations such as shale or tight use of more effective catalysts within facing profit constraints from the new sandstone. The use of tight oils reduces existing PT units is the quickest and most Tier 3 regulations, including optimized the severity of operations required to meet cost-effective solution. hydrotreatment and isomerization HDS and hydrodenitrification targets, but catalysts, gasoline-sulfur reduction often requires more guard catalysts. Gasoline sulfur additives additives and butylene-maximizing and octane-enhancing FCC catalysts. Albemarle has examined numerous The use of gasoline sulfur additives such case studies and conducted simulations as Albemarle’s Resolve technology may assist in lowering the sulfur content of FCC

8 ALBEMARLE CATALYST COURIER ISSUE 86 FCC-PT catalysts such as Albemarle’s accessibility catalyst technology, enhances Rising to the challenge Ketjenfine® (KF) 907 STARS® and KF 905N gasoline octane and butylenes while The Tier 3 regulations will present a STARS have been specially designed for preserving transportation fuels. significant challenge to many US refinery FCC-PT applications. KF 907 STARS is a When formulated into an FCC catalyst, operators. Some that had planned to rely very high activity Type I hydrotreating the new zeolite shifts the balance between on sulfur credits, which can be used during catalyst that can be used for a wide range isomerization and cracking toward the period 2017–2018, are finding that this of feedstocks. It is particularly well suited the former. What occurs, therefore, is may not be a straightforward solution. for FCC-PT applications where its very branching of the longer-chain FCC naphtha Each refinery needs to develop a long-term high desulfurization levels can deliver components, as opposed to cracking. The strategy that will meet its specific needs in low-sulfur FCC gasoline without sacrificing result is increased octane with minimal terms of productivity, upfront investment denitrogenation and hydrogenation conversion of gasoline to LPG. Moreover, and operating costs. performance. the isoparaffins that contribute much of the octane gain are unaffected by any PT Albemarle has an extensive toolkit for KF 905N STARS is a high-activity NiCoMo processes to remove sulfur. addressing environmental compliance catalyst that uses STARS technology to challenges while enhancing customer ensure near 100% Type II active sites. HDS activity and octane profitability. Contact us for help and In addition to a high desulfurization selectivity advice about overcoming your sulfur and capability, it offers excellent stability in Conventional hydrotreating to reduce octane challenges. high-severity operations and with metal- sulfur in gasoline has the unfortunate containing feedstocks. side effect of saturating olefins and Reference thereby reducing octane. In preparation 1Skurca, M. et al.: An action plan to improve FCC Octane has become a key issue for many for Tier 3 regulation and optimization unit performance at the Marathon Galveston Bay refiners with the advent of tight oil, more- of performance, Albemarle proposed its refinery,” paper AM-17-48 presented at the AFPM efficient car engines, the almost worldwide Annual Meeting 2017, San Antonio, TX, USA (March next-generation catalyst for selective 19–21, 2017) ban on the use of lead as a gasoline gasoline hydrotreating process: RT-235. additive and continuing pressure on octane This catalyst was a joint development blending components. The drive to ever- by ExxonMobil and Albemarle resulting lower sulfur specifications is making this from test screening of about 500 catalyst FOR MORE INFORMATION, CONTACT: even more of an issue because most PT formulations to ensure optimized support Dave Clary Email: [email protected] designed to remove sulfur from gasoline structure and metals distribution. also reduces its octane. The aim was to develop a catalyst that Albemarle’s ACTION FCC catalysts provide ƒƒ improved selectivity to save additional higher-octane gasoline and a higher yield octane of valuable C components with excellent 4 ƒƒ increased HDS activity to handle more olefinicity, which enables refiners to severe feedstocks with higher sulfur maximize operation of the alkylation unit levels and increase gasoline pool octane. ƒƒ improved carbon monoxide tolerance to prevent octane loss. New zeolite technology Following a detailed study of FCC reaction RT-235 has excellent selectivity to mechanisms, which crucially centered on desulfurization reactions while significantly the way that higher olefins are broken boosting overall desulfurization activity. down, Albemarle scientists developed a The extra desulfurization activity can new zeolite technology, ADZT™ 100. This provide significant economic benefits, provides unique cracking chemistry and, especially on units that require a relatively when used in combination with high- high level of desulfurization.

ALBEMARLE CATALYST COURIER ISSUE 86 9 TECHNICAL FOCUS

HELP WITH OPTIMIZING YOUR REFINERY OPERATIONS

Useful advice for refiners

George Yaluris’s answers to the can be 2 to 3 road octane numbers (RON) before gasoline hydrotreating became following questions, which were or more, most of the loss comes from RON common. It does have the obvious posed during the FCC session at the reduction due to olefins hydrogenation, drawback of decreasing gasoline yield, but 2016 American Fuel & Petrochemical whereas the motor octane number (MON) it can be utilized if the economics favor Manufacturers Q&A and Technology reduction is less. directing the heavy cut naphtha to the Forum in Baltimore, USA, on distillate stream. September 25–28, 2016, offer useful It is important to map the sources of advice for refiners. The first discusses gasoline sulfur and the streams that feed Gasoline octane loss during hydrotreating operating and catalytic changes to into the naphtha hydrotreater carefully. can be reduced by separating out the light FCC for lowering gasoline sulfur In general, if the FCC feed contains highly cat naphtha portion of the gasoline before while retaining octane and the second paraffinic tight oils or severely hydrotreated hydrotreating it. As light cat naphtha is feeds, the cat naphtha will be lower the most olefinic and the highest in RON looks at options for optimizing the C4 olefin yield of an alkylation unit. in sulfur and thus require less-severe fraction, hydrotreating it has the largest hydrotreating, which will result in a smaller negative impact on RON. Examples Q1: What FCC operating and catalytic octane loss. Consequently, the whole train include treating the gasoline in a selective changes can lower gasoline sulfur while of cat feed hydrotreater, FCC unit and hydrogenation unit; separating a lower-sulfur retaining octane? How would feed naphtha hydrotreater should be optimized light cat naphtha stream and using a Merox hydrotreatment affect these options? in terms of its operation and the catalysts unit to remove the sulfur from the light cat How would the FCC operating and being used in order to identify the most naphtha, and then, if needed, hydrotreating catalytic changes affect gasoline post- advantageous operating scheme. the light cat naphtha less severely. hydrotreating? A1: The strategy for reducing gasoline As the heavier and most aromatic portion It may be possible to decrease the octane sulfur and preserving octane has to be, of the gasoline contains most of the sulfur loss and improve the overall profitability by necessity, customized to the specific and this sulfur is the hardest to remove, by redirecting some of the streams. For configuration, the feeds being processed the sulfur level can be reduced without example, it may be better to drop the heavy and the octane needs of the refinery. While significant RON loss by undercutting the cat naphtha into the LCO and send it to a the octane lost by gasoline hydrotreating gasoline. This method was in frequent use hydrocracker, if one is available, while sending

10 ALBEMARLE CATALYST COURIER ISSUE 86 HELP WITH OPTIMIZING YOUR REFINERY OPERATIONS

more straight-run distillate to the FCC unit. octane. Each one should be considered in If they are effective at decreasing gasoline However, the impact of more distillate in the conjunction with the other FCC unit and the sulfur, they reduce the need for more-severe FCC feed on the yields, including the gasoline refinery objectives to arrive at the overall operation of the naphtha hydrotreater octane, must be considered. economic impact before its adoption: and, therefore, decrease the octane loss. ƒƒ Increasing the riser temperature will However, the performance history of If the refinery has an alky unit that is not increase octane, conversion, LPG make gasoline sulfur additives is uneven. Multiple fully utilized, the refiner could consider and olefinicity. factors, including the feed properties and increasing the production of alky feed from ƒƒ Using a catalyst containing a lower composition, and the unit configuration and the FCC unit in order to make more low- amount of rare earth and/or increased operation, can affect their performance. sulfur, high-octane alkylate. As additional matrix activity will help to raise the In addition, the efficacy of these additives alky feed production from the FCC unit gasoline octane. However, less rare earth at low levels of gasoline sulfur (less than often comes at the expense of gasoline, may mean that the catalyst is less active 30 ppm) has not been fully ascertained. the lower cat naphtha contribution to the and, thus, necessitate an increase in Where they have been shown to work, gasoline pool may enable a reduction in catalyst additions. It will also affect the they have decreased gasoline sulfur by as the hydrotreating unit’s severity, thereby amount of gasoline and LPG being made. much as 30%. Figure 1 shows a summary of decreasing the octane loss. ƒƒ ZSM-5 additives are well known to the performance of Albemarle’s RESOLVE increase gasoline octane and the family of gasoline sulfur reduction additives. Catalyst technologies for naphtha concentration of high-octane aromatic hydrotreaters continue to evolve, so components. However, ZSM-5 additives Q2: What operational and catalytic re‑examining the catalyst in the unit and can decrease gasoline production, as changes can be implemented to optimize

the operating conditions, could facilitate a they convert most of it to propylene. the C4 olefin yield of an alkylation unit? decrease in octane loss. ƒƒ Catalyst suppliers are also marketing A2: In recent years, the production of C4 catalysts that are formulated to help olefins from FCC units has been negatively Another option is to start with a higher increase gasoline octane. affected by the feeds being processed, cat naphtha octane. There are several Gasoline sulfur reduction technologies have including tight oils produced by fracking. strategies that can help to increase gasoline been around for more than two decades. These crude oils are highly paraffinic and >>>

0.15

0.10

70 4 Low aromatic sulfur feedstock TC

60 /

High aromatic sulfur feedstock 4= 0.05 50

40 0 30

20 Change in C –0.05 10

Gasoline sulfur reduction (%) 0 –0.10 0 5 10 15 20 25 30 35 40 –20 –10 0 10 20 Additive (%) Riser temperature change (°F)

Figure 1: Summary of a RESOLVE gasoline sulfur reduction additive’s Figure 2: Example of C4 olefinicity change with riser temperature. performance.

ALBEMARLE CATALYST COURIER ISSUE 86 11 TECHNICAL FOCUS

>>> result in a decrease of both LPG olefinicity time riser, riser termination devices and/ catalyst additions, and it will affect the and gasoline octane. This trend has or a new stripper. None of them are readily amount of gasoline and LPG being made. happened at the same time that the values available options and all of them require The gasoline olefinicity will also increase. of alkylate and gasoline octane have been significant capital investment. at their highest in the last two decades. ZSM-5 additives are well known to increase

Consequently, many refiners are looking for For increasing the C4 olefins production of the LPG olefins make in the FCC unit at the ways to increase alky feed production from an alky unit, catalytic options are typically expense of gasoline. However, traditional

the FCC, mostly C4 olefins. easier to implement and likely to be cheaper. ZSM-5 additives primarily convert gasoline to propylene: butylenes are secondary There are several operating options that can In addition to increasing the riser products. Thus, they are inefficient options

result in an increase in the C4 olefins yield. temperature, the refiner can use a more- for increasing C4 olefins production for use active catalyst and/or more catalyst in the in an alky unit unless there is also room Increasing the riser temperature is an unit in order to push the unit conversion to use the extra propylene being made effective option that increases the LPG higher, as shown in Figure 3. or propylene is a high-value product for make and improves olefinicity, including another application.

the C4 olefins yield, as Figure 2 shows. Unless the catalyst is specifically designed However, if this is implemented, it will also with low hydrogen transfer and high Albemarle also has catalysts and increase conversion and dry gas, as the riser matrix activity, this option will typically additives available that promise to

temperature is the strongest operating require higher rare earth content in increase C4 olefins production selectively. driver for dry gas make. If the unit is the catalyst, which will decrease the In Albemarle’s experience, catalyst operating in distillate maximization mode, olefinicity. In addition, the conversion is technologies specifically formulated to

increasing the riser temperature may not be high enough in many units that the C4 increase C4 olefins production are currently a good option. olefinicity will likely decrease even if the quite popular in North America. Figure 5

yield increases, see Figure 4. show an example of the C4 olefinicity If tight oils are being processed, efforts should improvement that can be expected be made to try to minimize the amount of The combination of decreasing the rare with Albemarle’s ACTION™ catalyst light straight-run distillate going to the FCC earth content and/or increasing the matrix technology. This technology is discussed in unit, as this is quite paraffinic and has the activity and overall accessibility is, in greater detail in Yaluris and Kramer (2014).1 largest negative impact on LPG olefinicity. many cases, the most effective option, as it will increase both the LPG olefins yield Reference If possible, the refiner could attempt and the olefinicity by increasing olefin 1Yaluris, G. and Kramer, A.: “Take ACTION™ – To to decrease the hydrocarbon partial production and decreasing hydrogenation maximize distillate and alky feed from your FCC pressure in the riser. The hydrocarbon reactions. Unless the catalyst is redesigned unit,” paper AM-14-26 presented at the American partial pressure is a key driver of the to maintain the activity, decreasing the Fuel & Petrochemical Manufacturers 2014 Annual Meeting, Orlando, FL, USA (March 23–25) reactions converting LPG olefins into rare earth content can make the catalyst paraffins. Decreasing the hydrocarbon less active, thus requiring an increase in partial pressure in the riser can be accomplished by decreasing the unit pressure or increasing the inerts. However, in Albemarle’s experience, a significant 3 change in hydrocarbon partial pressure

cannot be achieved without undertaking 2 a unit turnaround. This option is easier to implement with a grassroots unit. Because 1

decreasing the hydrocarbon pressure will yield (vol%) 4= 0 also decrease conversion, the catalyst will have to be redesigned to help recover –1 some of the lost conversion.

Change in C –2

Decreasing the residence time in the riser –3 and the reactor, and improving stripping –8 –4 0 4 8 will also decrease the secondary reactions Unit conversion change (vol%) and improve olefinicity. However, this Figure 3: Example of C olefins yield change with unit conversion. option may require a new short contact 4

12 ALBEMARLE CATALYST COURIER ISSUE 86 ALBEMARLE HAS CATALYSTS AND ADDITIVES

AVAILABLE THAT PROMISE TO INCREASE C4 OLEFINS PRODUCTION SELECTIVELY. IN ALBEMARLE’S EXPERIENCE, CATALYST TECHNOLOGIES SPECIFICALLY

FORMULATED TO INCREASE C4 OLEFINS PRODUCTION ARE CURRENTLY QUITE POPULAR IN NORTH AMERICA.

FOR MORE INFORMATION, CONTACT: George Yaluris Email: [email protected]

0.85

C3 olefinicity 0.15 0.80

0.10

4 Figure 5: C3 and C4

TC 0.75 olefinicity increases /

4= 0.05 in an FCC unit using C olefinicity Albemarle’s ACTION 0.70 4 catalyst technology 0 after normalizing for

Change in C feed and operating –0.05 0.65 differences. LPG olefinicity (wt%/wt%) –0.10 0.60 –20 –10 0 10 20 Unit conversion change (vol%) 0.55 Reference ACTION Figure 4: Example of C4 olefinicity decrease with unit conversion.

ALBEMARLE CATALYST COURIER ISSUE 86 13 TECHNICAL FOCUS OPTIMIZING VENDORS’ BIDS

Best practices for using FCC simulation models in the catalyst bid process

At Albemarle, we have noted an as, “I want to make sure all vendors’ Regardless of why refiners choose to use increase in the number of refiners projections hydrogen balance,” and “If process modeling, it is clear that these including model results as part I give everyone the same starting point models are becoming permanent fixtures. of the FCC catalyst bid package and same model, it should be easy to The challenge, and focus of this article, requirements, especially in the past pick the winner,” define this group. becomes how to get the most benefit from two years. Although a variety of FCC ƒƒ Some have been instructed by upper the process model when using it as a tool in models has been developed over management to use models. “The the FCC catalyst bid process. the past few decades, the industry refinery manager believes in models,” is coalescing around the FCC-SIM and “We invested heavily and want to Be realistic model developed by KBC Advanced see returns on that investment,” are Be realistic in setting your expectations. Technologies. This model combines the statements we have collected from The most common issue we see is level of sophistication and accuracy refiners in this situation. engineers underestimating the amount required by those of us in the industry, ƒƒ Finally, some refiners wish to of work required to define the base case along with a large user community. investigate the catalyst’s performance and to make sure that the model can in other situations. “We want to know predict correctly. Learning how to use the Refiners have given us many reasons for how different catalysts compare if FCC model can be a tremendous learning requiring model results as part of the conditions change from those given experience, but using the catalyst bid overall bid package. These reasons fall into in the bid package,” and “We want to process as the entry point into one’s foray three groups: compare catalysts in another operating into modeling may be akin to jumping ƒƒ Some believe the model results provide mode [such as comparing results from straight into the deep end of a pool. We an increased level of understanding and a maximum gasoline operation with recommend that engineers first become a reduced level of risk associated with a maximum distillate operation],” are versed in using the model for regular the catalyst change. Comments such typical comments from these users. monitoring of their FCC unit and can

14 ALBEMARLE CATALYST COURIER ISSUE 86 OPTIMIZING VENDORS’ BIDS

undertake predict cases for operational and feed changes without difficulty before evaluating a catalyst.

Choosing the base case and verifying the model’s abilities are undoubtedly the most important and probably the most WE RECOMMEND THAT ENGINEERS FIRST time-consuming parts of the process. The BECOME VERSED IN USING THE MODEL FOR quality of a bid projection will only be as good as the quality of the base case and REGULAR MONITORING OF THEIR FCC UNIT the tuning of the model you give to the AND CAN UNDERTAKE PREDICT CASES FOR catalyst vendors. OPERATIONAL AND FEED CHANGES WITHOUT DIFFICULTY BEFORE EVALUATING A CATALYST. As a catalyst bid is a forward-looking process and you are choosing the catalyst for a future expectation of operations, perhaps with a different feed or product demand scenario, you will likely want to use the expected future conditions as the base ƒƒ The feed density should fall within The next recommended step is to create case for the catalyst vendors. However, this approximately 0.02 kg/l or 2 API of trend plots of the calibration result dataset. creates a problem in setting up the model. typical feed. Check the results for reasonableness, but You can only calibrate the model to existing ƒƒ The cases should all be for the same pay particular attention to the hydrogen (past) data. So, how do you then create an combustion mode and the same as the balance, the hydrogen content of the coke, accurate base case for future conditions? base case for your catalyst projection. the heat of cracking, the catalyst-to-oil Answering this question is where most of For refineries with a single regenerator ratio and the estimated core aromatics the work in setting up the catalyst bid lies. that operates either partial or full content and distribution. burn, segregate the cases according to An accurate base case combustion mode. Finally, the calibration factor values often First, identify the calibrated cases available. provide the best insight as to the quality It is wise to collect as many as possible Once you have identified the initial pool of the raw data and the ability of the because the vetting process may quickly of calibration cases, evaluate the quality model to assimilate the data. Albemarle whittle down the number of usable cases. of each case. A good, quick option is to recommends plotting the “important” The following are a few of the best practices trend every single variable entered on the calibration factors and noting any flyers, Albemarle has established for identifying calibration input sheet graphically to find trends or variability in these factors. As whether you should include or eliminate a cases with flyers or atypical values, trends with the input and result data, you should calibration case: over time or high variability in the input thoroughly investigate, understand ƒƒ The cases must all be for the same data. Correct flyers whenever possible; and correct any anomalies noted in the catalyst formulation. Avoid cases otherwise, eliminate the case. If you find calibration factor plots or discard the case, –– during catalyst transition periods trends, investigate whether the trend as applicable. You can obtain a list of the –– where purchased E-cat is used correlates with a trend in any calibration most-important calibration factors for the at a rate 25% outside the typical factors possibly related to that independent FCC-SIM model, their typical values and amount variable. If a correlation exists, investigate the impact of catalyst formulation on these –– where the purchased E-cat the data further for quality issues. Either factors from Albemarle. An example of an properties are clearly atypical. manual tuning of the model or the important calibration using “fake” data is ƒƒ The cases should all be within 20% of elimination of some cases may be required. shown in Figure 1. the typical feed rate. >>>

ALBEMARLE CATALYST COURIER ISSUE 86 15 TECHNICAL FOCUS

>>> 1.5 Variability Flyers Trends 1.4

1.3

1.2 1.1

1.0

0.9

0.8

0.7 Conversion kinetic (XKUP 9) 0.6

0.5 1 Aug 2016 21 Aug 2016 10 Sept 2016 30 Sept 2016 20 Oct 2016 9 Nov 2016 29 Nov 2016 19 Dec 2016

Figure 1: The conversion kinetic value is an important calibration factor.

After vetting the calibration input data, results and factors, you should use as many PROCESS SIMULATION MODELS SUCH cases as possible of those that remain to AS FCC‑SIM ARE GAINING TRACTION IN establish the base case for the catalyst bid. THE INDUSTRY AS VALUABLE TOOLS FOR Although the process is simpler, Albemarle does not recommend merely selecting SUPPORTING DECISION-MAKING PROCESSES. a single day, known as a “super day”, THIS IS EVIDENT IN THE GROWING USE OF THESE from the candidate cases. Investigations MODELS AS AN INTEGRAL PART OF REFINERS’ have found that predictions based on a FCC CATALYST BID PROCESS. single super day chosen at random from a collection of high-quality super-day candidates can vary by a surprisingly large amount.1 Rather, it is recommended that the base cases’ variables be appropriately averaged to yield a single case. You should then calibrate this new averaged case and compare the input data, results data, and calibration factor data as before against the individual cases comprising it.

Unfortunately, creating the averaged case for the calibration set is not the end-point; it is only the halfway point of the bid preparation process. The second step, which is often neglected, is to verify, and correct, as necessary, the underlying predictive accuracy of the model.

16 ALBEMARLE CATALYST COURIER ISSUE 86 Verifying predictive capability be responsible for ensuring the correct Valuable tool To verify the validity of the model’s catalyst and metals balance target is used In conclusion, process simulation models predictive capability, you should use the so that the catalyst addition rate, activity, such as FCC-SIM are gaining traction averaged calibration case as developed up and E-cat metals are correct. in the industry as valuable tools for to this point. To establish the predictive supporting decision-making processes. accuracy of the model, copy the averaged Preparing for deployment This is evident in the growing use of these calibration case into the predict sheet, When preparing the bid base case for models as an integral part of refiners’ along with its calibration factors. Key deployment, run the bid base case to verify FCC catalyst bid process. As with any independent operational variables smooth operation of the model. You should model, the benefit strongly depends on such as riser and feed temperatures, provide each catalyst vendor with identical the quality of data input and the care feed rate and individual feed properties workbooks and FCC-SIM flowsheets. To taken to ensure that the model is tuned should be varied individually across ensure consistency in results and an apples- to provide accurate predictive results. The their range of experienced and expected to-apples comparison, we recommend best practices offered in this article can values. Then compare the results from specifying the version of FCC-SIM that the be used as a guide to help ensure the best these single variable step-out cases catalyst vendor(s) should execute. results possible when utilizing a process with actual experience to gauge the simulation model in conjunction with predictive accuracy of the model. If KBC Technologies currently supports your upcoming catalyst bid. you find a disconnect between the version 4.1 through version 6.2 of the model’s results and experience, use FCC-SIM model. Older versions are neither Reference the manual tuning factors to tune the supported nor available for download. We 1Kramer A., “How can I use FCC-SIM to monitor my model to align it with observations. recommend refiners utilize the most up-to- FCC unit regularly?” KBC Users’ Group Conference, date and technically advanced version of Houston, Texas, USA (September 2015) You should establish the predict scenario the model available. Also, vendors typically for the FCC catalyst bid base case before license only the FCC-SIM reactor model. If FOR MORE INFORMATION, CONTACT: submitting it to the vendors. Now is the your process flowsheet include objects not Alan Kramer Email: [email protected] time to change the feed properties of included with the FCC-SIM license, such the base case if you desire the catalyst to as crude distillation units, feed or product optimize the unit under a different feed hydrotreaters, other reactor models or feed than run in the average calibration case. assays, the vendor will be unable to execute You should also specify the predict targets the model. The flowsheet should only options to be used for the stripper, spent contain the FCC unit, the main fractionator, catalyst recycle, regenerator, oxygen the naphtha distillation columns and the enrichment and pressure balance, as component product splitters representing applicable. The catalyst vendor should the FCC unit gas plant.

ALBEMARLE CATALYST COURIER ISSUE 86 17 TECHNICAL FOCUS SMOOTHFLOW™: CIRCULATION CURE-ALL

SMOOTHFLOW fluidization aid extends operations having damaged cyclones and helps post-repair start-up

The modern FCC unit is a complex As gas is passed through the FCC catalyst, SMOOTHFLOW: Solutions harmony of physical and chemical it first flows through the interparticle voids Cyclone damage processes for upgrading low-value of a packed bed. At a minimum velocity Within cyclones, the capture efficiency hydrocarbons. The harmony depends (Umf), drag forces overcome gravity and substantially on the reliable retention interparticle friction, and the bed expands is directly related to the particle size, and transportation of fluidized to a fluid, free-flowing state. Such a state is among other factors. When holes form catalyst through the reaction and ideal for smooth, steady transfer of catalyst in the cyclone, the F45 fraction and regeneration zones. When fluidization from one part of the FCC unit to another. even larger particles can be rapidly deteriorates or becomes erratic, the At a higher velocity (the minimum bubbling lost. Increased catalyst additions are a suboptimal solution, as such action does FCC unit may shut down completely, velocity, Umb), distinct bubbles form in the violate environmental permits or fluid catalyst. These bubbles can restrict not preferentially restore the smaller- reduce profitability. Albemarle’s catalyst transfer or flow. sized particles vital to fluidization and SMOOTHFLOW fluidization aid lost most rapidly. The superior solution (Table 1) can mitigate these problems The ratio of the minimum fluidization is SMOOTHFLOW fluidization aid, which and help refiners continue operations velocity (U ) to the minimum bubbling contains a very large fraction of particles in mf the 30–80-µm range (Figure 1). until a planned maintenance period. velocity (Umb) is a key parameter for fluidization. Refiners operating with a higher ratio of U to U have a wider Dipleg malfunctions FCC unit fluidization basics mb mf The fluidization of FCC catalyst is a well- operating window for stable catalyst The cyclone diplegs are responsible for studied subject. The key, influencing factors circulation. Equation 1 shows that the returning captured particles to the bulk, ratio depends on the gas density (ρ ), the fluidized bed. Some diplegs are finished are illustrated in Equation 1: g gas viscosity (μ), the particle density (ρp), with flapper valves that prevent ingress the particle size (dp) and gravity (g). The of gas and fluid catalyst (a short circuit). influence of fines (percentage <45 µm, If these valves become stuck, the cyclone F45) and dp is of utmost importance. overloads and the FCC unit loses catalyst Albemarle’s SMOOTHFLOW additive has a to the overhead. Smaller particles are lost Equation 1. high value of F45 and a lower value for dp; most rapidly. SMOOTHFLOW additive

both of which increase the ratio of Umb to assists operability by preferentially

Umf and facilitate stable operation. restoring this particle size range.

100 90 SMOOTHFLOW 80 Normal FCC 70 60 50 40

than (vol%) 30 20 Relative activity SMOOTHFLOW Inactive product 10 Cumulative amount finer 0 10 100 1000 0 5 10 15 20 Diameter (µm) Circulation additive (%)

Figure 1: SMOOTHFLOW fluidization aid has a large Figure 2: SMOOTHFLOW fluidization aid contains active amount of 30–80-µm particles that tangibly benefit matrix and zeolite components to prevent activity loss in units circulation and fluidization. requiring higher amounts of additive to correct the particle size distribution.

18 ALBEMARLE CATALYST COURIER ISSUE 86 SMOOTHFLOW™: CIRCULATION CURE-ALL

Standpipe stress includes Albemarle’s proprietary ADM-20 bottoms upgrading matrix and proprietary Many refiners use aeration taps along zeolite technologies. It can be used very standpipes to aid catalyst flow from reactor aggressively without worry about dilution to regenerator. When these taps become effects or significant yield alterations. plugged, flow may become erratic and lead Some competitive products have little or to an unstable ΔP across the slide valves no cracking activity. Although these other or physical stress (for example, standpipe products may relieve some circulation movement). Since SMOOTHFLOW issues, they can significantly lower the fluidization aid fluidizes more easily activity of the circulating catalyst and and deaerates more slowly than normal create new problems (Figure 2). The active catalyst, it can provide immediate relief. ingredients in SMOOTHFLOW fluidization Start-up difficulties aid make it the preferred solution for units needing significant additive to correct the When a refinery shuts down an FCC unit particle size distribution. to repair the cyclones and other critical hardware, it may have difficulty restarting References on the exceptionally coarse E-cat. In one 1Geldart, D. and Radtke, A. L.: “The effect of case, a refiner’s catalyst de-fluidized in particles on the behaviour of equilibrium cracking the diplegs, bridged the cross section and catalysts in standpipe flow,” Powder Technology created a plug. With SMOOTHFLOW (1986), 47(2), 157–165 2 fluidization aid, this refiner recovered stable “A fine solution to FCC unit start-up problems,” Catalyst Courier 76, 15 operations within a day.

SMOOTHFLOW: Fluidization with activity FOR MORE INFORMATION, CONTACT: A key advantage of SMOOTHFLOW Ryan Nickell additive compared with competitive Email: [email protected] products is its tangible cracking activity. It

TYPICAL PRODUCT PROPERTIES ADDITIVE NAME SMOOTHFLOW APPLICATION Fluidization additive SURFACE AREA, M2/G 205 PARTICLE SIZE DISTRIBUTION (0–40), % 24 PARTICLE SIZE DISTRIBUTION (0–20), % 6 ATTRITION INDEX, WT% 4.7 SURFACE AREA, M2/G 0.71

Table 1: Typical properties for SMOOTHFLOW fluidization aid.

ALBEMARLE CATALYST COURIER ISSUE 86 19 CASE STUDY

KETJENFINE® (KF) 780 STARS®: AN INTELLIGENT OPTION FOR FCC PRETREATMENT (FCC-PT) APPLICATIONS Meeting the challenges of clean fuel hydrotreating needs

As discussed in a previous high hydrodesulphurization (HDS) to (CFHT) units, the need for deeper HDN Catalyst Courier article1, meet environmental regulations on and greater HDA to improve FCC yields gasoline sulfur content and FCC unit SOx and selectivities has increased. refiners increasingly need emissions to produce ultra-low-sulfur b) reduce nitrogen and aromatics levels To meet these market needs, Albemarle gasoline and more diesel fuel, by maximizing hydrodenitrogenation has researched extensively across its which can be challenging. (HDN) and hydrodearomatization (HDA) customers’ operations to determine for improving FCC unit product yields, how best to help them meet their Therefore, FCC-PT units are selectivities and operations needs. It became clear that variations increasingly more important c) increase the conversion of VGO to in FCC-PT operating conditions, feeds, in helping to overcome this diesel-range products. unit objectives and unit constraints challenge, so they require In addition, controlling FCC-PT catalyst fill often make it impractical for a single costs and achieving target cycle lengths are catalyst to fulfill all a refiner’s needs and robust and reliable catalyst generally high priorities. wants. Albemarle concluded that STAX systems for high activity and technology solutions for FCC-PT are good stability. No single FCC-PT unit is representative of preferable for enabling customers to meet this process application: units are designed the challenges encountered in almost all Albemarle’s VGO STAX®–FCC-PT is the and operated to fit specific refinery their CFHT applications. preferred technology solution to enable operating strategies and objectives. Consequently, FCC-PT units cover a broad customers to meet the FCC-PT challenges KF 780 STARS – an intelligent in their refineries. Albemarle has wide- range of feed properties and operating ranging global refinery operational insights variables. These units can be characterized catalyst addition that help it to identify customers’ needs, by operating objectives and hydrogen KF 780 STARS is the latest CoMo catalyst

constraints and opportunities. Strong partial pressures (ppH2) ranging anywhere addition to Albemarle’s hydroprocessing

process and technology application from low (inlet ppH2 <55 bar, <800 psi) to portfolio. It is a Type II catalyst suitable

expertise enables the company to advise “high” (inlet ppH2 >90 bar, 1300 psi). Units for FCC-PT and diesel hydrotreating customers on the preferred catalyst in Europe, the Middle East and India are applications, which makes it ideal for systems and operating tactics for meeting mostly in the low- to moderate-pressure cascading between different refinery their operating objectives. To bolster this range and are typically operated to achieve applications. This high-activity HDS technical expertise, Albemarle uses a deep HDS and, in some cases, to increase catalyst can be a standalone catalyst or a proprietary computer process modeling conversion of VGO feed to diesel product. key component in a STAX configuration capability, which gives highly reliable North American units tend to fall primarily for FCC-PT. performance estimates, to generate in the moderate- to high-pressure range. and assess catalyst loading design Although many of these units focus on The defining feature of KF 780 STARS recommendations for customers. HDS, others focus on maximizing HDN catalyst is its extremely high metals and HDA. efficiency. This step out was achieved Unlike processes that produce clean fuel through improved metals dispersion and tailored distribution of active sites products directly, the economic value Albemarle’s viewpoint of FCC-PT is largely from how well it coupled with better pore accessibility. improves FCC unit product yields, product In recent years, product sulfur targets This combination of almost 100% Type II qualities and operations. Depending on have become even lower and the need active sites and superior metals efficiency the refinery, the key objectives for FCC-PT for more active and stable catalysts has gives this catalyst exceptional activity and operations may be to increased. In addition, for moderate- to stability in even the most-demanding VGO a) maintain a low product sulfur level with high-pressure catalytic feed hydrotreating hydrotreating applications. These enable it

20 ALBEMARLE CATALYST COURIER ISSUE 86 to help refiners overcome constraints and exploit opportunities.

Figure 1 shows the typical application regimes for KF 780 STARS catalyst in conjunction with Albemarle’s overall FCC-PT catalyst portfolio. Each catalyst is available in two or three sizes to provide solutions for any refining objective in terms of activity, stability, hydrogen consumption and/or avoiding pressure drop issues. Each catalyst can be deployed in various ways using VGO STAX FCC-PT technology.

Figure 2 illustrates how KF 780 STARS catalyst provides value to refiners. A high activity and relatively low loading density give this catalyst superior FCC- PT performance without increasing fill costs. It also enables refiners to upgrade KF 780 STARS catalyst – Commercial Case A is a low-pressure FCC-PT unit (ppH inlet ∼42 bar, 610 psi) lower value feeds and/or to achieve Commercial examples 2 operating in constant HDS mode. The deeper HDS to decrease the sulfur in FCC KF 780 STARS catalyst is now in 11 different unit has two reactors in series treating a products and reduce SOx generation. This VGO commercial hydrotreating units blend of heavy VGO and middle distillates, is especially important for enabling North (Table 1). Two FCC-PT cases follow to including cracked stock, to about American refiners without FCC naphtha illustrate how this catalyst can provide 600‑ppmw sulfur (current cycle) in the post-treatment capabilities to meet Tier 3 increased operating benefits to refiners. total liquid product (TLP). The TLP is sent ultra-low sulfur gasoline regulations. In both cases, KF 780 STARS catalyst was to the FCC unit without fractionation. The Finally, KF 780 STARS catalyst has also originally selected on the basis of in-house bottleneck in the operation is the product been successful for those refiners trying pilot plant testing; its superior commercial sulfur of the FCC naphtha (25–35 ppmw), to increase VGO conversion and increase performance justified its selection for which determines the operating weighted diesel fuel production. subsequent cycles also. average bed temperature (WABT) of the FCC-PT process. Hence, the operating

SR VGO SR VGO/heavy cracked GO/DAO FCC-PT value Loading density Low catalyst density Cycle length KF 860 STARS KF 870 STARS results in effective fill costs and fill costs HDN/aromatic without sacrificing KF 861 STARS High performance saturation limited KF 851 STARS Medium Low + FCC unit conversion Profits HDS limited Ability to upgrade low-value Margin for KF 905N STARS feeds resulting in improvement improved FCC unit = refiners KF 907 STARS performance KF 780 STARS + KF 905 STARS Conversion increase Ability to achieve increased Production

Hydrogenation activity STAX conversion and diesel increase product yield 30 50 80 120 bar 450 750 1150 1750 psi

Outlet ppH2

Figure 1: Albemarle’s FCC-PT catalyst portfolio. Figure 2: KF 780 STARS catalyst gives value to refiners at all

ppH2 levels. >>>

ALBEMARLE CATALYST COURIER ISSUE 86 21 CASE STUDY

>>> incentive is to boost HDS as much as possible. The cycle length requirement is NUMBER OF typically 18 months to satisfy the refinery’s COUNTRY SERVICE AMOUNT (T) UNITS turnaround schedule. AUSTRIA Mild hydrocracking-PT 67 1 FINLAND FCC-PT 305 1 In the previous cycle, in view of the very GERMANY FCC-PT 221 1 low ppH2 and necessity for very high LITHUANIA FCC-PT 109 1 HDS activity, the unit was loaded with a UNDISCLOSED FCC-PT 83 1 combination of KF 905 STARS catalyst (Reactor 1) and KF 757 STARS catalyst SPAIN FCC-PT 409 2 (Reactor 2), which achieved a successful INDIA FCC-PT 448 1 run. In the current cycle, supported by very COLOMBIA FCC-PT 17 1 positive customer test results, the unit’s CANADA FCC-PT 133 1 catalyst system was improved by replacing USA FCC-PT 49 1 the KF 757 STARS catalyst in Reactor 2 and much of the KF 905 STARS catalyst in Table 1: KF 780 STARS catalyst sales to VGO hydrotreating units. Reactor 1 with KF 780 STARS catalyst.

The main value proposition was to reduce CYCLE 1 (PREVIOUS) CYCLE 2 (CURRENT) product sulfur in the FCC naphtha while treating a similar FCC-PT feedstock. Table 2 KF 905 STARS catalyst + compares the first 280 days of operation MAIN CATALYST KF 757 STARS catalyst KF 780 STARS catalyst of the previous (Cycle 1) with the current P /PPH INLET, BAR 48/43 47/41 TOT 2 cycle with KF 780 STARS catalyst (Cycle 2). FEED RATE, M3/H 352 368 The feed properties were similar for the two HYDROGEN/OIL RATIO, NL/L 258 220 cycles (slightly more difficult for Cycle 1), AVERAGE FEED PROPERTIES (FIRST 280 DAYS ONSTREAM) but the operating conditions in Cycle 2 were SULFUR, WT% 1.44 1.35 more demanding to achieve deeper HDS: on average, ~4.5% more feedstock was treated NITROGEN, PPMW 1184 1076 over the same period in Cycle 2 and the DENSITY AT 15°C, G/ML 0.903 0.899 inlet ppH2 (41 versus 43 bar, or 595 versus BROMINE NUMBER, G/100 G 2.8 2.8 625 psi) and hydrogen-to-oil ratio (220 AVERAGE FEED PROPERTIES (FIRST 280 DAYS ONSTREAM) versus 258 Nl/l, or 1300 versus 1530 scf/ SULFUR, PPMW 786 585 (∼200 lower) bbl) were lower. START OF RUN WABT, °C; °F ∼357; 675 ∼360; 680 KF 780 STARS catalyst has consistently NORMALIZED WABT AT 786-PPMW 357; 675 352; 666 (–5°C; –9°F) delivered 200-ppmw (~25%) lower TLP SULFUR, °C; °F product sulfur in Cycle 2 for the derived CYCLE LENGTH, MONTHS 18 18 (projected) benefit of lowering the FCC naphtha sulfur concentration by at least 7 ppmw and Table 2: Commercial Case A: Comparison between commercial cycles 1 and 2. probably by ≥10 ppmw. If the WABT at the start of run is normalized for the difference in feed and product properties and for the main operating conditions, the WABT advantage that KF 780 STARS catalyst provided was approximately 5°C (9°F) compared with the KF 905 STARS–KF 757 STARS system for a 800-ppmw sulfur level in the TLP.

Normalized deactivation in this cycle was lower, i.e., less than 1.5°C/month (2.7°F/ month) compared with 1.8°C/month

22 ALBEMARLE CATALYST COURIER ISSUE 86 700 80 77.4 624 Previous cycle KF 780 STARS cycle 72.3 600 60 500 374 400 366 2000 1821 40 300 1500 25.8 205 922 910 20.3 200 1000 741 20 100 500 1.6 1.8 81 83 0 0 0 Naphtha Diesel DVGO Sulfur (ppmw) T95% ASTM Sulfur (ppm) Density Aniline point (C5–150°C) (150–360°C) (360+°C) cut point (°C) Yields (wt% versus feed) Diesel quality DVGO quality

Figure 3: Commercial Case B: yields and qualities for the KF 780 STARS catalyst cycle versus the previous cycle.

(3.2°F/month) over the same period in mode for the first two months onstream benefits can be achieved in stand-alone the previous cycle. This result testifies and produced ultra-low-sulfur diesel applications and as a key component in to the better stability of KF 780 STARS (ULSD). After switching to the higher- VGO STAX FCC-PT catalyst systems that catalyst, despite the more demanding temperature, higher-conversion operating are tailored to achieve customers’ needs operating conditions. mode, the catalyst deactivation rate and objectives. remained low (2.1°C/month, 3.8°F). Net Commercial Case B is an FCC-PT unit VGO conversion was 5.1 wt% higher than This catalyst has shown very good operating at moderate pressure (ppH2 for the previous cycle, with only a 0.2 wt% performance in customer pilot unit testing inlet ~53 bar) and on oil for more than higher naphtha yield and a 5.5 wt% higher and its first eight commercial applications. 18 months, even though the original cycle diesel yield, see Figure 3. The figure also It is too early to report on the other three length target was 12 months. The primary shows that the diesel product for this cycle commercial units because they have either objective for this unit at Repsol’s Petronor contained significantly less sulfur, which not yet started up or are very early in their refinery in Spain was to increase VGO enabled the refinery to make an 8°C (14°F) cycles. KF 780 STARS catalyst is available conversion (third objective in Figure 2) higher cut point. in both 1.3Q and 3Q sizes, and is also from ~25 to ~30 wt% while ensuring that showing good performance in initial ULSD the FCC feed sulfur content remained The DVGO feed to the FCC unit has applications. That usage will be the subject below 700 ppmw throughout the run. The significantly lower sulfur, lower nitrogen of a future Catalyst Courier article. overall reactor loading consists of 28 vol% and aromatics levels, a slightly lower regenerated NiMo catalyst and 72 vol% density and a slightly higher aniline point Reference 1 KF 780 STARS catalyst. The feed is a blend than the DVGO for the previous cycle. Anderson, G.: “Flexibility for FCC pretreatment,” Catalyst Courier 84, 22–24 of straight-run VGO and heavy coker gas These feed improvements enabled the FCC oil with >3.0 wt% sulfur, >2300 ppmw unit to generate better yields than during Acknowledgement nitrogen and ~0.94 g/ml specific gravity the previous FCC-PT cycle. Repsol SA and, in particular, process engineer (19 API). Maria Moreno Pardo are acknowledged for kindly Through its positive experience with this granting to Albemarle permission to include its Repsol conducted pilot plant tests before cycle, Repsol chose KF 780 STARS catalyst refinery information and data in this publication. selecting a catalyst for this unit. In these again for the next cycle and for a similar tests, KF 780 STARS catalyst gave 4.6 wt% CFHT unit in another refinery. higher net conversion than the base case Summary FOR MORE INFORMATION, CONTACT: catalyst system, with a 0.8 wt% higher George Anderson naphtha yield and a 3.4 wt% higher diesel In conclusion, KF 780 STARS CoMo catalyst Email: [email protected] yield. Because of the higher conversion is a more intelligent catalyst for FCC-PT and better FCC-PT product qualities, the applications, as it spans all pressure regimes company selected KF 780 STARS catalyst and all operating objectives, with particular for the commercial unit. benefits in low- and moderate-pressure applications. It features high activity and The commercial operations have exceeded stability through step-out improvements Repsol’s expectations. The unit was run in in active site dispersion and utilization low-temperature, constant-product-sulfur efficiency. The performance and economic

ALBEMARLE CATALYST COURIER ISSUE 86 23 You deserve satisfACTION

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That’s because with its continuing record of success, Albemarle’s ACTION® is the only commercially proven FCC catalyst to maximize distillate, butylenes and octane with minimal gasoline loss. Utilizing its unique zeolite and matrix technologies, ACTION has been successful at cracking all types of feeds, from tight oil to heavy resid. Your success is too important to risk with unproven alternatives. Achieve satisfaction and success with the undisputed leader…demand ACTION.

For more information on Albemarle ACTION catalyst or our exceptional portfolio of products and services, call REFINING SOLUTIONS +1 281 480 4747 or visit www.albemarle.com. 24 ALBEMARLE CATALYST COURIER ISSUE 86