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Zn-Al Mixed Oxides Decorated with Potassium As Catalysts for HT-WGS: Preparation and Properties
catalysts Article Zn-Al Mixed Oxides Decorated with Potassium as Catalysts for HT-WGS: Preparation and Properties Katarzyna Antoniak-Jurak * , Paweł Kowalik, Kamila Michalska, Wiesław Próchniak and Robert Bicki Łukasiewicz Research Network—New Chemical Syntheses Institute, Al. Tysi ˛acleciaPa´nstwa Polskiego 13A, 24-110 Puławy, Poland; [email protected] (P.K.); [email protected] (K.M.); [email protected] (W.P.); [email protected] (R.B.) * Correspondence: [email protected]; Tel.: +48-8-1473-1754 Received: 8 September 2020; Accepted: 18 September 2020; Published: 21 September 2020 Abstract: A set of ex-ZnAl-LDHs catalysts with a molar ratio of Zn/Al in the range of 0.3–1.0 was prepared using co-precipitation and thermal treatment. The samples were characterized using various methods, including X-ray fluorescence spectroscopy (XRF), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy FT-IR, N2 adsorption, Temperature-programmed desorption of CO2 (TPD-CO2) as well as Scanning electron microscopy (SEM-EDS). Catalyst activity and long-term stability measurements were carried out in a high-temperature water–gas shift (HT-WGS) reaction. Mixed oxide catalysts with various Zn/Al molar ratios decorated with potassium showed high activity in the HT-WGS reaction within the temperature range of 330–400 ◦C. The highest activity was found for the Zn/Al molar ratio of 0.5 corresponding to spinel stoichiometry. However, the catalyst with a stoichiometric spinel molar ratio of Zn/Al (ZnAl_0.5_K) revealed a higher tendency for surface migration and/or vaporization of potassium during overheating at 450 ◦C. -
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.................................................. -
Former Fellows Biographical Index Part
Former Fellows of The Royal Society of Edinburgh 1783 – 2002 Biographical Index Part Two ISBN 0 902198 84 X Published July 2006 © The Royal Society of Edinburgh 22-26 George Street, Edinburgh, EH2 2PQ BIOGRAPHICAL INDEX OF FORMER FELLOWS OF THE ROYAL SOCIETY OF EDINBURGH 1783 – 2002 PART II K-Z C D Waterston and A Macmillan Shearer This is a print-out of the biographical index of over 4000 former Fellows of the Royal Society of Edinburgh as held on the Society’s computer system in October 2005. It lists former Fellows from the foundation of the Society in 1783 to October 2002. Most are deceased Fellows up to and including the list given in the RSE Directory 2003 (Session 2002-3) but some former Fellows who left the Society by resignation or were removed from the roll are still living. HISTORY OF THE PROJECT Information on the Fellowship has been kept by the Society in many ways – unpublished sources include Council and Committee Minutes, Card Indices, and correspondence; published sources such as Transactions, Proceedings, Year Books, Billets, Candidates Lists, etc. All have been examined by the compilers, who have found the Minutes, particularly Committee Minutes, to be of variable quality, and it is to be regretted that the Society’s holdings of published billets and candidates lists are incomplete. The late Professor Neil Campbell prepared from these sources a loose-leaf list of some 1500 Ordinary Fellows elected during the Society’s first hundred years. He listed name and forenames, title where applicable and national honours, profession or discipline, position held, some information on membership of the other societies, dates of birth, election to the Society and death or resignation from the Society and reference to a printed biography. -
'New Insights on the Selective Oxidation of Methanol to Formaldehyde on Femo Based Catalysts'
‘New Insights on the Selective Oxidation of Methanol to Formaldehyde on FeMo Based Catalysts' Catherine Brookes School of Chemistry Cardiff University Thesis for the degree of Doctor of Philosophy i This thesis was submitted for examination in August 2015. ii Abstract The selective oxidation of methanol has been studied in detail, with particular focus on gaining insights into the surface active sights responsible for directing the selectivity to formaldehyde. Various Fe and Mo containing oxides have been investigated for their reactivity with methanol, to gain an understanding of the different roles of these components in the industrial catalyst employed, which is a mixed phase comprised of MoO 3 and Fe 2(MoO 4)3. Catalysts have primarily been tested through using TPD (temperature programmed desorption) and TPPFR (temperature programmed pulsed flow reaction). The reactivity of Fe 2O3 is dominated by combustion products, with CO 2 and H 2 produced via a formate intermediate adsorbing at the catalyst surface. For MoO 3 however, the surface is populated by methoxy intermediates, so that the selectivity is almost 100 % directed to formaldehyde. When a mixture of isolated Fe and Mo sites co-exist, the surface methoxy becomes stabilised, resulting in a dehydrogenation reaction to CO and H 2. CO and CO 2 can also be observed on Mo rich surfaces, however here a consequence of the further oxidation of formaldehyde, through a linear pathway. TPD and DRIFTS identify these intermediates and products forming. Since the structure of the industrial catalyst is relatively complex, in that it contains both MoO 3 and Fe 2(MoO 4)3, it is difficult to identify the active site for the reaction with methanol. -
Direct Synthesis of Dimethyl Ether from Syngas on Bifunctional Hybrid
catalysts Article Direct Synthesis of Dimethyl Ether from Syngas on Bifunctional Hybrid Catalysts Based on Supported H3PW12O40 and Cu-ZnO(Al): Effect of Heteropolyacid Loading on Hybrid Structure and Catalytic Activity Elena Millán , Noelia Mota, Rut Guil-López, Bárbara Pawelec , José L. García Fierro and Rufino M. Navarro * Instituto de Catálisis y Petroleoquímica (CSIC), C/Marie Curie 2, Cantoblanco, 28049 Madrid, Spain; [email protected] (E.M.); [email protected] (N.M.); [email protected] (R.G.-L.); [email protected] (B.P.); jlgfi[email protected] (J.L.G.F.) * Correspondence: [email protected] Received: 27 August 2020; Accepted: 15 September 2020; Published: 17 September 2020 Abstract: The performance of bifunctional hybrid catalysts based on phosphotungstic acid (H3PW12O40, HPW) supported on TiO2 combined with Cu-ZnO(Al) catalyst in the direct synthesis of dimethyl ether (DME) from syngas has been investigated. We studied the effect of the HPW loading on TiO2 (from 1.4 to 2.7 monolayers) on the dispersion and acid characteristics of the HPW clusters. When the concentration of the heteropoliacid is slightly higher than the monolayer (1.4 monolayers) the acidity of the clusters is perturbed by the surface of titania, while for concentration higher than 1.7 monolayers results in the formation of three-dimensional HPW nanocrystals with acidity similar to the bulk heteropolyacid. Physical hybridization of supported heteropolyacids with the Cu-ZnO(Al) catalyst modifies both the acid characteristics of the supported heteropolyacids and the copper surface area of the Cu-ZnO(Al) catalyst. -
Platinum Metals Industrial Catalysts Catalysis of Organic Reactions EDITED by M
Platinum Metals Industrial Catalysts Catalysis of Organic Reactions EDITED BY M. G. SCAROS AND M. L. PRUNIER, Marcel Dekker, New York, 1995, 599 pages, ISBN 0-8247-9364-1, U.S. $195.00 This book comprises a set of papers presented reactant purity, agitation and poisons are at the 15th Conference on Catalysis of Organic considered. This is followed by a paper detail- Reactions, held in Phoenix, Arizona, in May ing noble metal recovery operations and the var- 1994. It covers a variety of topics, such as het- ious steps involved in the noble metal “loop”. erogeneous catalysis, asymmetric hydrogena- Heterogeneous catalysis in organic synthesis tion, hydrogenation, oxidation, hydroformyla- is discussed by R. L. Augustine and colleagues tion, catalyst design and catalyst characterisation. from Seton Hall University, New Jersey. This One topic which is emphasised is hydrogena- is illustrated by the platinum catalysed oxida- tion (alpha to omega), and this is intended to tion of alcohols, carbon-carbon bond forming allow a better understanding of the entire reactions of supported palladium catalysts for process, from choosing a catalyst to the noble the Heck type arylation of allylic groups, and metal “loop”. There are over 60 papers and 186 by enantioselective heterogeneous catalysis, contributors, with a healthy number of these which includes the hydrogenation of a-ketoesters being from industry. A large proportion of the to chiral a-hydroxyesters using chinchona alka- papers deal with reactions involving platinum loid modified platinum catalysts. group metal catalysts, reflecting their impor- A detailed study of the homogeneously pal- tance to both academia and industry. -
Charles Kemball Was One of the Most Distinguished British Chemists of His Generation
CHARLES KEMBALL CBE, MA, ScD(Cantab), DSc(H-W,QUB), C Chem, FRSC, MRIA, FRS Charles Kemball was one of the most distinguished British chemists of his generation. He was born in Edinburgh in 1923, the only son of a distinguished dental surgeon, Charles Henry Kemball FRSE , and was educated at Edinburgh Academy. It was clear from an early age that he was very talented and even in the preparatory school at Edinburgh Academy his teacher found his speed at mental arithmetic rather disconcerting. Bright pupils were encouraged towards the Classics and it was only after the School Certificate Examination that a perceptive teacher persuaded him to move to the Sciences. He had an aptitude at shooting and was a member of the shooting VIII which won the Kinder Cup at Bisley in 1939. Subsequently he was captain of shooting and won the shooting cup in his final two years at the Academy. Despite his late move to sciences he won an Entrance Exhibition in Natural Sciences and went up to Trinity College Cambridge in 1940. At this time his interests lay more with Mathematics and Physics but he later moved to Chemistry and gained First Class Honours in Parts I and II of the Tripos. He went on to do research in the Department of Colloid Science under the direction of Professor E K Rideal, financed by a grant from the Ministry of Aircraft Production, to investigate problems in adhesion. In addition to some direct investigations into the strength of various adhesives for metals, the main work undertaken was a detailed study of the adsorption of vapours on the surface of mercury, to determine the magnitude of the forces attracting the molecules to the metal. -
The Unique Interplay Between Copper and Zinc During Catalytic Carbon Dioxide Hydrogenation to Methanol ✉ Maxim Zabilskiy 1 , Vitaly L
ARTICLE https://doi.org/10.1038/s41467-020-16342-1 OPEN The unique interplay between copper and zinc during catalytic carbon dioxide hydrogenation to methanol ✉ Maxim Zabilskiy 1 , Vitaly L. Sushkevich1, Dennis Palagin 1, Mark A. Newton2, Frank Krumeich 2 & ✉ Jeroen A. van Bokhoven 1,2 fi 1234567890():,; In spite of numerous works in the eld of chemical valorization of carbon dioxide into methanol, the nature of high activity of Cu/ZnO catalysts, including the reaction mechanism and the structure of the catalyst active site, remains the subject of intensive debate. By using high-pressure operando techniques: steady-state isotope transient kinetic analysis coupled with infrared spectroscopy, together with time-resolved X-ray absorption spectroscopy and X-ray powder diffraction, and supported by electron microscopy and theoretical modeling, we present direct evidence that zinc formate is the principal observable reactive intermediate, which in the presence of hydrogen converts into methanol. Our results indicate that the copper–zinc alloy undergoes oxidation under reaction conditions into zinc formate, zinc oxide and metallic copper. The intimate contact between zinc and copper phases facilitates zinc formate formation and its hydrogenation by hydrogen to methanol. 1 Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, 5232 Villigen, Switzerland. 2 Institute for Chemistry and Bioengineering, ETH ✉ Zurich, Vladimir-Prelog-Weg 1, 8093 Zürich, Switzerland. email: [email protected]; [email protected] NATURE COMMUNICATIONS | (2020) 11:2409 | https://doi.org/10.1038/s41467-020-16342-1 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | https://doi.org/10.1038/s41467-020-16342-1 arbon dioxide is a principal anthropogenic pollutant, ris- catalyst for this highly important and industrially relevant Cing level of which has a detrimental effect on the envir- reaction. -
Heterogeneous Catalyst Deactivation and Regeneration: a Review
Catalysts 2015, 5, 145-269; doi:10.3390/catal5010145 OPEN ACCESS catalysts ISSN 2073-4344 www.mdpi.com/journal/catalysts Review Heterogeneous Catalyst Deactivation and Regeneration: A Review Morris D. Argyle and Calvin H. Bartholomew * Chemical Engineering Department, Brigham Young University, Provo, UT 84602, USA; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel: +1-801-422-4162, Fax: +1-801-422-0151. Academic Editor: Keith Hohn Received: 30 December 2013 / Accepted: 12 September 2014 / Published: 26 February 2015 Abstract: Deactivation of heterogeneous catalysts is a ubiquitous problem that causes loss of catalytic rate with time. This review on deactivation and regeneration of heterogeneous catalysts classifies deactivation by type (chemical, thermal, and mechanical) and by mechanism (poisoning, fouling, thermal degradation, vapor formation, vapor-solid and solid-solid reactions, and attrition/crushing). The key features and considerations for each of these deactivation types is reviewed in detail with reference to the latest literature reports in these areas. Two case studies on the deactivation mechanisms of catalysts used for cobalt Fischer-Tropsch and selective catalytic reduction are considered to provide additional depth in the topics of sintering, coking, poisoning, and fouling. Regeneration considerations and options are also briefly discussed for each deactivation mechanism. Keywords: heterogeneous catalysis; deactivation; regeneration 1. Introduction Catalyst deactivation, the loss over time of catalytic activity and/or selectivity, is a problem of great and continuing concern in the practice of industrial catalytic processes. Costs to industry for catalyst replacement and process shutdown total billions of dollars per year. Time scales for catalyst deactivation vary considerably; for example, in the case of cracking catalysts, catalyst mortality may be on the order of seconds, while in ammonia synthesis the iron catalyst may last for 5–10 years. -
Former Fellows Biographical Index Part
Former Fellows of The Royal Society of Edinburgh 1783 – 2002 Biographical Index Part One ISBN 0 902 198 84 X Published July 2006 © The Royal Society of Edinburgh 22-26 George Street, Edinburgh, EH2 2PQ BIOGRAPHICAL INDEX OF FORMER FELLOWS OF THE ROYAL SOCIETY OF EDINBURGH 1783 – 2002 PART I A-J C D Waterston and A Macmillan Shearer This is a print-out of the biographical index of over 4000 former Fellows of the Royal Society of Edinburgh as held on the Society’s computer system in October 2005. It lists former Fellows from the foundation of the Society in 1783 to October 2002. Most are deceased Fellows up to and including the list given in the RSE Directory 2003 (Session 2002-3) but some former Fellows who left the Society by resignation or were removed from the roll are still living. HISTORY OF THE PROJECT Information on the Fellowship has been kept by the Society in many ways – unpublished sources include Council and Committee Minutes, Card Indices, and correspondence; published sources such as Transactions, Proceedings, Year Books, Billets, Candidates Lists, etc. All have been examined by the compilers, who have found the Minutes, particularly Committee Minutes, to be of variable quality, and it is to be regretted that the Society’s holdings of published billets and candidates lists are incomplete. The late Professor Neil Campbell prepared from these sources a loose-leaf list of some 1500 Ordinary Fellows elected during the Society’s first hundred years. He listed name and forenames, title where applicable and national honours, profession or discipline, position held, some information on membership of the other societies, dates of birth, election to the Society and death or resignation from the Society and reference to a printed biography. -
The Royal Society of Chemistry Presidents 1841 T0 2021
The Presidents of the Chemical Society & Royal Society of Chemistry (1841–2024) Contents Introduction 04 Chemical Society Presidents (1841–1980) 07 Royal Society of Chemistry Presidents (1980–2024) 34 Researching Past Presidents 45 Presidents by Date 47 Cover images (left to right): Professor Thomas Graham; Sir Ewart Ray Herbert Jones; Professor Lesley Yellowlees; The President’s Badge of Office Introduction On Tuesday 23 February 1841, a meeting was convened by Robert Warington that resolved to form a society of members interested in the advancement of chemistry. On 30 March, the 77 men who’d already leant their support met at what would be the Chemical Society’s first official meeting; at that meeting, Thomas Graham was unanimously elected to be the Society’s first president. The other main decision made at the 30 March meeting was on the system by which the Chemical Society would be organised: “That the ordinary members shall elect out of their own body, by ballot, a President, four Vice-Presidents, a Treasurer, two Secretaries, and a Council of twelve, four of Introduction whom may be non-resident, by whom the business of the Society shall be conducted.” At the first Annual General Meeting the following year, in March 1842, the Bye Laws were formally enshrined, and the ‘Duty of the President’ was stated: “To preside at all Meetings of the Society and Council. To take the Chair at all ordinary Meetings of the Society, at eight o’clock precisely, and to regulate the order of the proceedings. A Member shall not be eligible as President of the Society for more than two years in succession, but shall be re-eligible after the lapse of one year.” Little has changed in the way presidents are elected; they still have to be a member of the Society and are elected by other members. -
High Temperature Water Gas Shift Catalysts: a Computer Modelling Study
High Temperature Water Gas Shift Catalysts: A Computer Modelling Study Sreelekha Benny Department of Chemistry University College London Johnson Matthey Technology Centre Thesis submitted for the degree of Doctor in Engineering March 2010 “It's our attitude at the beginning of a difficult undertaking which more than anything else will determine its successful outcome." William James (Father of American psychology) 2 Declaration ____________________________________________________________________ Declaration I, Sreelekha Benny confirm that the work presented in this thesis is the result of my own investigations and where information has been derived from other sources, this has been fully acknowledged. 3 Abstract ____________________________________________________________________ Abstract The high-temperature (HT) Water Gas Shift (WGS) reaction has considerable technological relevance for lowering CO content during the conversion of natural gas or liquid hydrocarbons to hydrogen. Conventional HT-WGS catalysts based on oxides of iron and chromium are well established industrially. However, it is crucial to remove any impurities present such as Cr6+, S or N during the catalytic process. In particular, Cr6+ is regarded as a Class I carcinogen and its presence is restricted by EU legislation. Even though Cr6+ is reduced during the catalytic process, caution must still be taken to eliminate any further impurities. Hence, it is desirable to identify alternative promoters and develop a Cr-free HT-WGS catalyst. This thesis presents results obtained using atomistic simulation techniques to investigate the effect of Cr3+ and possible alternative dopants in three important iron oxide materials, Hematite (α-Fe2O3), Maghemite (γ-Fe2O3) and Magnetite (Fe3O4). The starting point is to develop an understanding of the structural properties and distribution of Cr3+ on the bulk and surface material of hematite.