Heterogeneous Catalytic Oligomerization of Ethylene
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Opportunities for Catalysis in the 21St Century
Opportunities for Catalysis in The 21st Century A Report from the Basic Energy Sciences Advisory Committee BASIC ENERGY SCIENCES ADVISORY COMMITTEE SUBPANEL WORKSHOP REPORT Opportunities for Catalysis in the 21st Century May 14-16, 2002 Workshop Chair Professor J. M. White University of Texas Writing Group Chair Professor John Bercaw California Institute of Technology This page is intentionally left blank. Contents Executive Summary........................................................................................... v A Grand Challenge....................................................................................................... v The Present Opportunity .............................................................................................. v The Importance of Catalysis Science to DOE.............................................................. vi A Recommendation for Increased Federal Investment in Catalysis Research............. vi I. Introduction................................................................................................ 1 A. Background, Structure, and Organization of the Workshop .................................. 1 B. Recent Advances in Experimental and Theoretical Methods ................................ 1 C. The Grand Challenge ............................................................................................. 2 D. Enabling Approaches for Progress in Catalysis ..................................................... 3 E. Consensus Observations and Recommendations.................................................. -
Particle Size and Structural Effects in Platinum Electrocatalysis
JOURNAL OF APPLIED ELECTROCHEMISTRY 20 (1990) 537-548 REVIEWS OF APPLIED ELECTROCHEMISTRY 23 Particle size and structural effects in platinum electrocatalysis S. MUKERJEE Tata Energy Research Institute, 7 Jor Bagh, New Delhi-llO 003, India Received 4 January 1989; revised 18 October 1989 Of the several factors which influence electrocatalytic activity, particle size and structural effects are of crucial importance, but their effects and mechanism of interaction, vis-a-vis overall performance, have been, at best, vaguely understood. The situation is further aggravated by the use of a wide range of experimental conditions resulting in non-comparable data. This paper attempts systematically to present the developments to date in the understanding of these structural interactions and to point out areas for future investigation. The entire content of this review has been examined from the context of the highly dispersed Pt electrocatalyst, primarily because it has been examined in the greatest detail. In the first two sections a general idea on the correlations between surface microstructure and geometric model is presented. Subsequently, indicators of a direct correlation between particle size and catalyst support synergism are considered. The structural and particle size effect on electro- catalysis is examined from the point of view of anodic hydrogen oxidation and cathodic oxygen reduction reactions. The hydrogen and oxygen chemisorption effects, presented with the discussion on the anodic and cathodic electrocatalytic reactions, provide important clues toward resolving some of the controversial findings, especially on the dependence of particle size on the anodic hydrogen oxidation reaction. Finally, the effect of alloy formation on the cathodic oxygen reduction reaction is discussed, providing insights into the structural aspect. -
Monolithic Substrate Support Catalyst Design Considerations for Steam Methane Reforming Operation
Rev Chem Eng 2017; aop Luqmanulhakim Baharudin and Matthew James Watson* Monolithic substrate support catalyst design considerations for steam methane reforming operation DOI 10.1515/revce-2016-0048 as compared to other processes discussed by Baharudin Received October 16, 2016; accepted March 10, 2017 and Watson (2017). In this review paper, a monolithic structured packing for steam methane reforming (SMR) Abstract: This paper reviews the research undertaken to reactor will be studied. This novel reactor packing offers study the design criteria that address the monolithic sup- the benefits of overcoming the heat conduction limitation port structure requirements in steam reforming opera- in the current industrial-scale reformers, process intensi- tion for the effective mass transfer of process gases to the fication for an overall plant optimization, and materializ- active sites and effective conductive heat transfer through ing the concept of compact reformer. SMR is expressed by tube wall to the active catalytic areas, as well as low pres- (Saito et al. 2015). sure drop operation. Design considerations include selec- tion of substrate materials that possess good mechanical CH42+↔HO CO + 3 H2 (1) strength to withstand the severe reaction conditions and prevent catalyst crushing that would lead to carbon for- In a nutshell, a monolithic structure is a single structure mation and catalyst deactivation, and excessive heating consisting of thin-walled narrow channels that are paral- of the tube that results in hot spots which is fatal to tube lel to each other (Heck et al. 2001, Roy et al. 2004, Zamani- lifetime. The support’s mechanical properties are listed yan et al. -
1 the Structure and Reactivity of Single and Multiple
1 1 The Structure and Reactivity of Single and Multiple Sites on Heterogeneous and Homogeneous Catalysts: Analogies, Differences, and Challenges for Characterization Methods Adriano Zecchina , Silvia Bordiga , and Elena Groppo 1.1 Introduction The content of this book is specifi cally devoted to a description of the complexity of the catalytic centers (both homogeneous and heterogeneous) viewed as nanoma- chines for molecular assembling. Although the word “ nano ” is nowadays some- what abused, its use for catalysts science (as nanoscience) is fully justifi ed. It is a matter of fact that (i) to perform any specifi c catalytic action, the selective catalyst must necessarily possess sophisticated structure where substrates bonds are broken and formed along a specifi c path and (ii) the relevant part of this structure, usually constituted by a metal center or metal cluster surrounded by a sphere of ligands or by a solid framework or by a portion of functionalized surface, often reaches the nanometric dimension. As it will emerge from the various chapters, this vision is valid for many types of selective catalysts including catalysts for hydrogenation, polymerization, olygomerization, partial oxidation, and photocata- lytic solar energy conversion. Five chapters are devoted to the above - mentioned reactions. From the point of view of the general defi nition, homogeneous and heterogeneous selective catalysts can be treated in the same way. As homogeneous selective catalysts are concerned, the tridimensional structure surrounding the metal center can be organized with cavitand shape, while for heterogeneous cata- lysts the selectivity is the result of an accurate design and synthesis of the frame- work structures (often microporous and crystalline) where the sites are anchored. -
SILICA CATALYSTS High Performance Polyolefin Catalysts & Supports High Performance Polyolefin Catalysts & Supports
SILICA CATALYSTS High Performance Polyolefin Catalysts & Supports High Performance Polyolefin Catalysts & Supports World class PQ is a key global supplier of chrome-on-silica catalysts and modified chrome catalysts, widely used catalysts & supports in the polymerization of ethylene into polyethylene. designed to With a manufacturing history stretching back over give exceptional 200 years, PQ prides itself on being a manufacturer performance within that offers customers; the polyolefin • Consistent product quality market • Reliable product supply • Customised solutions • Expert technical service PQ silica supports are used in the production of • HDPE chrome, Ziegler-Natta and single site catalysts that are subsequently used to manufacture polyethylene, • LLDPE polypropylene and other polymers. These polymers • PP are used in a wide variety of applications including films and sheets, pipes and tubes, blow-moulded containers and automobile parts, and wire and • Gas Phase cable sheathings. • Slurry Phase PQ supports are used in both gas-phase and slurry- phase processes. High Performance Polyolefin Catalysts & Supports THE BENEFITS OF PQ PRODUCTS High Purity As a result of the strict control of raw materials and advanced process technologies, PQ produces silica supports that have low levels of impurities. PQ is the world leader in the production of sodium silicate, a key raw material in the production of silica supports, so the quality of this critical feedstock is directly managed. Uniform Products Through the careful control of critical process steps, PQ produces products that are highly uniform at both a macroscopic level (batch to batch consistency) and a microscopic level (particle to particle uniformity). Customizable Catalysts In addition to chrome-on-silica PQ also offers modified chromium catalysts containing aluminium, titanium and other elements to provide performance enhancements needed for certain end uses, such as reduced induction time and increased activity, melt flow index and ESCR. -
Heterogeneous Catalysis Using Supported Metal Nanoparticles for Environmental Applications
Heterogeneous catalysis using supported metal nanoparticles for environmental applications Thesis submitted in accordance with the regulations of the University of Cardiff for the degree of Doctor of Philosophy By Khaled Fadhi F. Alshammari School of Chemistry Cardiff University 2018 Declaration This work has not been submitted in substance for any other degree or award at ths or any other university or place of learning, nor is being submitted concurrently in candidature for any degree or other award. Signed………………………………………… (candidate) Date …………………..... Statement 1 This thesis is being submitted in partial fulfilment of the requirements for the degree of ……PhD……….. (insert MCh, MD, MPhil, PhD, etc, as appropriate). Signed………………………………………… (candidate) Date …………………..... Statement 2 This thesis is the result of my own independent work/investigation, except where otherwise stated, and the thesis has not been edited by a third party beyond what is permitted by Cardiff University’s Policy on the Use of Third-Party Editors by Research Degree Students. Other sources are acknowledged by explicit references. The views expressed are my own. Signed………………………………………… (candidate) Date …………………..... Statement 3 I hereby give consent for my thesis, if accepted, to be available online in the University’s Open Access repository and for inter-library loan, and for the title and summary to be made available to outside organisations. Signed………………………………………… (candidate) Date …………………..... Statement 4: Previously Approved Bar on Access. I hereby give consent for my thesis, if accepted, to be available online in the University’s Open Access repository and for inter-library loans after expiry of a bar on access previously approved by the Academic Standards and Quality Committee. -
Graphene As Catalyst Support: the Influences of Carbon Additives and Catalyst Preparation Methods on the Performance of PEM Fuel Cells
CARBON 58 (2013) 139– 150 Available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/carbon Graphene as catalyst support: The influences of carbon additives and catalyst preparation methods on the performance of PEM fuel cells Angela Marinkas a, Francesco Arena a, Jens Mitzel a,Gu¨ nther M. Prinz b, Angelika Heinzel c, Volker Peinecke c, Harald Natter a,* a Saarland University, Physical Chemistry, Campus Geb. B2 2, D-66123 Saarbru¨ cken, Germany b University Duisburg-Essen, Experimental Physics and CENIDE, Lotharstraße 1, D-47057 Duisburg, Germany c ZBT Duisburg, The Fuel Cell Research Center GmbH, Carl-Benz-Str. 201, D-47057 Duisburg, Germany ARTICLE INFO ABSTRACT Article history: The reduction of the platinum amount for efficient PEM (polymer electrolyte membrane) Received 17 November 2012 fuel cells was achieved by the use of graphene/carbon composites as catalyst support. Accepted 19 February 2013 The influences of the carbon support type and also of the catalyst preparation method Available online 27 February 2013 on the fuel cell performance were investigated with electrochemical, spectroscopic and microscopic techniques. Using pure graphene supports the final catalyst layer consists of a dense and well orientated roof tile structure which causes strong mass transport limita- tions for fuels and products. Thus the catalysts efficiency and finally the fuel cell perfor- mance were reduced. The addition of different carbon additives like carbon black particles or multi-walled carbon nanotubes (MWCNT) destroys this structure and forms a porous layer which is very efficient for the mass transport. The network structure of the catalyst layer and therefore the performance depends on the amount and on the morphol- ogy of the carbon additives. -
Three-Way Catalysts in Passive Selective Catalytic Reduction Systems Calvin Thomas
University of South Carolina Scholar Commons Theses and Dissertations Fall 2018 Three-Way Catalysts in Passive Selective Catalytic Reduction Systems Calvin Thomas Follow this and additional works at: https://scholarcommons.sc.edu/etd Part of the Chemical Engineering Commons Recommended Citation Thomas, C.(2018). Three-Way Catalysts in Passive Selective Catalytic Reduction Systems. (Doctoral dissertation). Retrieved from https://scholarcommons.sc.edu/etd/5067 This Open Access Dissertation is brought to you by Scholar Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. THREE-WAY CATALYSTS IN PASSIVE SELECTIVE CATALYTIC REDUCTION SYSTEMS by Calvin Thomas Bachelor of Chemical Engineering Auburn University, 2013 Submitted in Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy in Chemical Engineering College of Engineering and Computing University of South Carolina 2018 Accepted by: Jochen Lauterbach, Major Professor William Mustain, Committee Member Erdem Sasmaz, Committee Member Todd Toops, Committee Member Cheryl L. Addy, Vice Provost and Dean of the Graduate School © Copyright by Calvin Thomas, 2018 All Rights Reserved. ii DEDICATION This work is dedicated to my brothers and sisters: Micah, Megan, Charles, Jessica, and Alexandra. They have been with me through my whole life and I wouldn’t be where or who I am without them. It is also dedicated to my dog Fritz because he is a very good boy. iii ACKNOWLEDGEMENTS First and foremost, I would like to thank my advisor, Professor Jochen Lauterbach for accepting me into the Strategic Approaches to the Generation of Electricity (SAGE) research group. -
Recent Advances of Titanium Dioxide (Tio2) for Green Organic Synthesis
RSC Advances View Article Online REVIEW View Journal | View Issue Recent advances of titanium dioxide (TiO2) for green organic synthesis Cite this: RSC Adv.,2016,6,108741 Lee Eng Oi,a Min-Yee Choo,a Hwei Voon Lee,a Hwai Chyuan Ong,b Sharifah Bee Abd Hamida and Joon Ching Juan*ac Titanium dioxide (TiO2) has become increasingly popular as a catalyst. Although many applications of TiO2 involve photocatalysis and photoelectrochemical reactions, there are numerous interesting discoveries of TiO2 for other reactions. This review focuses on the recent development of TiO2 as a catalyst in green organic synthesis including in hydrodeoxygenation, hydrogenation, esterification/transesterification, the water–gas shift reaction, and visible light-induced organic transformation owing to its strong metal- Received 13th September 2016 support interaction (SMSI), high chemical stability, acidity, and high redox reaction at low temperature. Accepted 29th October 2016 The relationship between the catalytic performance and different metal or metal oxide dopants, and DOI: 10.1039/c6ra22894a different polymorphs of TiO2 are discussed in detail. It is interesting to note that the reduction www.rsc.org/advances temperature and addition of promoters have a significant effect on the catalytic performance of TiO2. sized scale, can iname the lungs. An occupational daily expo- 1. Introduction 8 sure limit of 15 mg of TiO2 dust has been set by the OSHA. Titanium dioxide is known as titanium(IV) oxide or titania, with Unlike other dust, TiO2 dust does not cause scarring as it is not the chemical formula TiO2. Compared with bulk TiO2, TiO2 chemically irritating to the lungs. -
Reduced Graphene Oxide-Supported Pt-Based Catalysts for PEM Fuel Cells with Enhanced Activity and Stability
catalysts Article Reduced Graphene Oxide-Supported Pt-Based Catalysts for PEM Fuel Cells with Enhanced Activity and Stability Irina V. Pushkareva 1,2 , Artem S. Pushkarev 1,2,3 , Valery N. Kalinichenko 2,4,5, Ratibor G. Chumakov 2,3, Maksim A. Soloviev 1,2, Yanyu Liang 6, Pierre Millet 7 and Sergey A. Grigoriev 1,2,8,* 1 National Research University “Moscow Power Engineering Institute”, 14, Krasnokazarmennaya st., 111250 Moscow, Russia; [email protected] (I.V.P.); [email protected] (A.S.P.); [email protected] (M.A.S.) 2 National Research Center “Kurchatov Institute”, 1, Akademika Kurchatova sq., 123182 Moscow, Russia; [email protected] (V.N.K.); [email protected] (R.G.C.) 3 Moscow Institute of Physics and Technology, 9, Institutskiy per., Dolgoprudny, 141701 Moscow Region, Russia 4 N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia 5 N.M. Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia 6 College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China; [email protected] 7 Institut de Chimie Moléculaire et des Matériaux d’Orsay, Université Paris-Saclay, 91405 Orsay, France; [email protected] 8 HySA Infrastructure Center of Competence, Faculty of Engineering, North-West University, Potchefstroom 2531, South Africa * Correspondence: [email protected] or [email protected] Citation: Pushkareva, I.V.; Pushkarev, A.S.; Kalinichenko, V.N.; Abstract: Platinum (Pt)-based electrocatalysts supported by reduced graphene oxide (RGO) were Chumakov, R.G.; Soloviev, M.A.; synthesized using two different methods, namely: (i) a conventional two-step polyol process using Liang, Y.; Millet, P.; Grigoriev, S.A. -
Basic Research Needs for Catalysis Science
Basic Research Needs for Catalysis Science Report of the Basic Energy Sciences Workshop on Basic Research Needs for Catalysis Science to Transform Energy Technologies May 8–10, 2017 Image courtesy of Argonne National Laboratory. DISCLAIMER This report was prepared as an account of a workshop sponsored by the U.S. Department of Energy. Neither the United States Government nor any agency thereof, nor any of their employees or officers, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of document authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Copyrights to portions of this report (including graphics) are reserved by original copyright holders or their assignees, and are used by the Government’s license and by permission. Requests to use any images must be made to the provider identified in the image credits. This report is available in pdf format at https://science.energy.gov/bes/community-resources/reports/ REPORT OF THE BASIC RESEARCH NEEDS WORKSHOP FOR CATALYSIS SCIENCE Basic Research Needs for Catalysis Science TO TRANSFORM ENERGY TECHNOLOGIES Report from the U.S. Department of Energy, Office of Basic Energy Sciences Workshop May 8–10, 2017, in Gaithersburg, Maryland CHAIR: ASSOCIATE CHAIRS: Carl A. -
Low Cost/Waste Catalyst for Fatty Acid Methyl Ester Production
Article Number: 2AEBF76 A Paper presented at the 39th CSN Annual International Conference, Workshop and Exhibition, Rivers State University of Science and Technology, Port Harcourt, Nigeria. 18th – 23rd September 2016 Copyright ©2018 Author(s) retain the copyright of this article Conference Proceedings http://www.proceedings.academicjournals.org/ Full Length Research Paper Low cost/waste catalyst for fatty acid methyl ester production M. O. Ekeoma1*, P. A. C. Okoye2 and V. I. E. Ajiwe2 1Department of Chemistry, College of Physical and Applied Sciences, Michael Okpara University of Agriculture, Umudike, P. M. B. 7267, Umuahia, Abia State, Nigeria. 2Department of Pure and Industrial Chemistry, Faculty of Physical Sciences, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria. Non-edible crude karanj (Pongamia pinnata) oil (CKO) with high free fatty acid (FFA) content was used as effective renewable feedstock for fatty acid methyl ester (FAME) production. Calcium feldspar clay, a rare compositional variety of plagioclase clay, a low cost, abundant earth resource, containing over 90% CaO and belonging to the class of anorthite clay was used as heterogeneous catalyst in direct conversion of high FFA crude karanj oil to fatty acid methyl esters. The efficiency of the catalyst was made possible by the structural rearrangement of the mixed metal oxides' content of the catalyst at prolonged high temperatures, a behaviour characteristic of glass transitions and properties of amorphous phases of plagioclase feldspar, and thus was transformed into solid acid particles such as acidic mesoporous aluminium silicate mixed oxides. Optimum FAME yield of 98.97% was obtained at 4 h reaction time, 6 wt% catalyst loading, 9:1 methanol to CKO molar ratio and at methanol reflux temperature.