Alkylation A Key to Cleaner Gasoline & Better Vehicle Mileage

The American Fuel & Petrochemical Manufacturers (AFPM) is the leading trade association representing the makers of the fuels that keep us moving, the petrochemicals that are the essential building blocks for modern life and the midstream companies that get our feedstocks and products where they need to go. We make the products that make life better, safer and more sustainable — we make progress. U.S. gasoline needs alkylate for (OSHA) Process Safety Management and projects to transition from HF to Refineries that are close to chemical facil- its octane and environmental program and the Environmental even newer alkylation technologies are ities may have the option of selling their properties Protection Agency’s (EPA) Risk still in early phases. Eliminating the use propylene and butylene as feedstocks Management Program. But refineries that of either HF or sulfuric acid technology to manufacture plastics and sanitizers. America’s fuel refiners use a chemical use HF go even further. Because nothing would severely diminish U.S. capacity to For refineries without this option, HF Alkylation is a refinery process called alkylation to produce is more important to the refining industry manufacture cleaner gasoline in line with alkylation technology provides an answer Refinery alkylation process essential to the alkylate, a component of the cleaner than the safety of our people and consumer demand. where sulfuric acid technology does not. is subject to layers gasoline required by today’s higher- communities, facilities with HF alkylation HF units can co-process both propylene production of cleaner fuels efficiency automobiles. Nearly 90 U.S. units also adhere to exacting industry and butylene to make alkylate. of regulation and that satisfy the world’s refineries — representing 90% of total U.S. policies — that go above and beyond The myth of interchangeable accountability, including refining capacity — have alkylation units. what is required by law — to manage risk alkylation technology Alkylation optionality toughest air quality, and keep refining employees, contractors Research into alternative alkylation strict oversight from: Alongside varying combinations of Multiple factors dictate which alkylation and neighbors safe. technologies is ongoing, but HF and sulfuric carbon emissions and ethanol, reformate and other products, technology a refinery will use, including feedstocks, space constraints, trans- acid are still the only commer­cially proven auto efficiency standards. alkylate increases the octane rating of catalysts available to refiners today. gasoline which works to reduce premature portation logistics and refinery location. Fuel alkylation is part of The selection of an alkylation catalyst Part of the reason for this is the refining Industry and auditors, combustion and “engine knock” that can industry’s exacting commitment to the American success damage a vehicle and downgrade engine Once an alkylation unit has impacts configuration of the entire per comprehensive refinery operation and its other process safety and reliability. Engineers and story of doubling fuel efficiency. In optimized engines, higher- been designed and built scientific researchers follow a multi-year, API RP-751 policies octane gasoline supports better vehicle units. Once a technology is chosen and to use a specific catalyst, the alkylation unit is designed and built to multi-step process to test new fuel economy, reducing vehicle performance and fuel economy, and lower alkylation technologies, which includes: OSHA carbon emissions by half overall greenhouse gas emissions. Beyond it cannot be switched use a specific catalyst, refineries cannot contributing octane, alkylate also brings flip a switch and swap to the other. HF · Bench-scale testing to demonstrate to operate on the other and sulfuric acid technologies are not and cutting national air to the table other unique environmental feasibility of chemistry EPA interchangeable. pollutant emissions nearly attributes that help vehicles run cleaner, without major equipment · Pilot plant testing to verify process viability namely low measures of fuel volatility and modifications that would 80% since the 1970s. evaporative emissions —represented by · Demonstration unit testing to determine Department of low Reid Vapor Pressure (RVP) —that are be infeasible for most scalability and evaluate process, Homeland Security essential in parts of the country where facilities to execute. The components and material compatibility smog is a concern. Additionally, because alkylate has no aromatic content and low two catalyst technologies · Commercial unit testing to confirm Department of sulfur, it helps lower vehicle emissions are not interchangeable scalability and ongoing reliability Defense and tailpipe pollution. and require completely · At least one or two turnaround cycles IHS Markit trends suggest global demand (three – five years each) to evaluate safety Chemical Safety different reactor systems. and reliability over time, and to monitor for alkylate will rise nearly 10% by 2030 Square footage and feedstock volume Board as more countries motorize. Investments Sulfuric units require more energy and equipment and unit components for the to expand alkylate production capacity space than HF units. Sulfuric alkylation effects of corrosion and other potential wear worldwide will be needed to supply this While HF alkylation and sulfuric acid requires more acid catalyst, which means State and local larger market. alkylation both accomplish the same there must be additional feedstock Both solid acid catalyst (e.g., AlkyClean, thing — producing alkylate for the deliveries and a larger overall reactor. K-SAAT) and ionic liquid alkylation technol- authorities manufacture of high-octane, low RVP Additionally, sulfuric acid units require ogies (e.g., ISOALKY, Ionikylation) are being Two alkylation technologies gasoline and aviation fuel — there are a refrigeration system and access to explored and show considerable promise. support cleaner fuel significant differences in their processing acid regeneration units, either onsite or As of January 2021, ISOALKY is the only The alkylation process requires a catalyst configurations, equipment and risk nearby. These are not considerations for other technology in operation in the to enable a chemical reaction that safely mitigation strategies, though neither facilities with HF units. United States apart from HF and sulfuric converts feedstocks into alkylate. Sulfuric technology is inherently safer. acid. More time and testing are needed to acid and hydrofluoric acid (HF) are the Location and waste reduction ensure these newer technologies can safely two commercially proven alkylation Decommissioning one type of alkylation Alkylation technology is often a reflection and efficiently produce the compo­nents catalysts used today, each accounting for unit to rebuild around the other of other feedstocks produces onsite. That of cleaner gasoline in a range of differently about half of U.S. alkylate production. technology would be a massive under- means other refinery processes and sized and configured refineries. taking for a facility, and many would find proximity to petrochemical plants factor into Both catalysts are used safely by fuel it impossible given other considerations the decision around alkylation catalysts. Recent progress suggests that new unit refineries around the country and in a wide at their sites. In fact, there is no proven builds and conversions may become range of other industrial settings. They commercial pathway for refineries to Refineries do not waste product, and economically feasible. But we still have a are thoroughly regulated by state and switch from one alkylation catalyst to the complex refineries with fluid catalytic lot to learn. We don’t yet know what total federal workplace and community safety other. No refinery has ever converted an cracking units (FCC units) need to have a costs are associated with the adoption of programs, including the Occupational HF unit over to sulfuric acid alkylation, system in place to utilize their propylene newer catalysts or the reliability of these Safety and Health Administration’s and butylene byproducts. technologies over time. Other refinery processes Butane Isomerization support alkylation & the Butane isomerization converts butane production of cleaner fuels produced by refineries, including FCC units, to isobutane. While butane is also America is home to some of the most a source of octane, it needs to be limited sophisticated and advanced refineries in finished gasoline to keep evaporative in the world. Our complex refineries emissions low, per the Clean Air Act’s feature several interconnected processes Reid Vapor Pressure (RVP) rules. Converting that each play a part in turning crude excess butane into isobutane through oil — even the toughest-to-refine heavy isomerization creates a valuable sour types — into fuels clean enough feedstock for refinery alkylation units. for today’s high-performance engines and stringent U.S. air quality and auto Catalytic Reformer emissions standards. Alkylation and isomerization units aren’t the only sources of fuel octane at refin- Alkylation units allow refineries to upgrade eries. Catalytic reformers produce octane lower value feedstocks into high value too — converting low-octane naphtha alkylate. Other refinery units produce (produced during crude distillation) into the feedstocks required for alkylation, so high-octane reformate to be blended into wherever fuel alkylation units are located gasoline. Whether gasoline is regular, These highly interrelated you will typically find one or more of the midgrade or premium, reformate is likely and sophisticated processes following complementary processes nearby: a source of some of its octane (along with alkylate, butane and ethanol). Like the are used throughout the Fluid catalytic cracking (FCC) butane isomerization process, isobutane country to turn a broad A fluid catalytic cracking unit, often called is a byproduct of catalytic reforming that a “cat cracker,” “cat unit,” or “FCC,” makes range of crude oil and can be used to support alkylation. it possible to convert low value, heavy gas hydrocarbons into the oil (what some might call “the-bottom- Hydrocracker of-the-barrel”) into higher value products Hydrocracking units perform similar cleaner fuels Americans — like gasoline. The process also generates functions as FCC units, but tend to help and the world — depend on. butane, propylene, and butylene refineries maximize diesel fuel production. byproducts that serve as building blocks Hydrocrackers turn heavier hydrocarbons for a wide range of consumer products, into lighter products suitable for distillates and, separately, as feed for a refinery’s HF as well as gasoline and jet fuel. But where Alkylation and the future of alkylation unit. Without a process like cat the FCC unit produces propylene and liquid fuels cracking to enable product optionality from butylene olefins, hydrocracking produces U.S. refiners set the bar globally for a range of crude oils, refineries would have straight isobutane — ready-made to feed process safety, reliability and maximizing a much harder time producing the exact an alkylation unit. the production of cleaner fuels from even products demanded by the global market. the toughest-to-refine crude oils. The How it all connects to alkylation alkylation process that yields low-sulfur, Each of the above processes can be a high-octane alkylate is core to modern complement to alkylation. In alkylation refining and delivers a cleaner future for Other refinery units units, a concentrated catalyst, such as U.S. auto transportation. produce byproducts that hydrofluoric acid or sulfuric acid, kicks off feed the alkylation process. a chemical reaction where alkylate is made Internal combustion engine vehicles from olefins and isobutane feedstocks only function at their best when they’re produced by other refinery processes. running on the right kinds of fuel — Alkylate is a critical fuel component the specific fuel prescribed by their that is high in octane, low in sulfur and manufacturer. Cleaner, higher octane Reid Vapor Pressure and contains zero gasoline helps optimized engines reach aromatics or olefins — features of the their maximum efficiency. Alkylate cleanest gasoline on the market. from U.S refineries is a key component of this gasoline and helps bring to life the benefits of fuel economy and cleaner driving for consumers and the environment.

American Fuel & Petrochemical Manufacturers · afpm.org