Pub Date : 2013-10-01DOI: 10.1595/147106713X672221
Alfa Aesar
{"title":"PGMs in the Lab: New, Efficient Tools for Palladium-Catalysed Functionalisation of Heteroaromatics","authors":"Alfa Aesar","doi":"10.1595/147106713X672221","DOIUrl":"https://doi.org/10.1595/147106713X672221","url":null,"abstract":"","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"311-312"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X672221","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1595/147106713X671222
Oliver T. Holton, J. W. Stevenson
Johnson Matthey, Orchard Road, Royston, Hertfordshire SG8 5HE, UK Email: *oliver.holton@matthey.com; **joe.stevenson@matthey.com Proton exchange membrane fuel cells (PEMFCs) dominate the transportation fuel cell market and platinum (Pt) is the catalyst material used for both anode and cathode. This review sets out the fundamentals of activity, selectivity, stability and poisoning resistance which make Pt or its alloys the best available materials to use in this application. It is clear that Pt is the only element which can meet the requirements for performance while avoiding slow reaction kinetics, proton exchange membrane (PEM) system degradation due to hydrogen peroxide (H2O2) formation and catalyst degradation due to metal leaching. Some of the means by which the performance of Pt can be enhanced are also discussed.
英国赫特福德郡罗伊斯顿乌节路SG8 5HE Johnson Matthey邮箱:*oliver.holton@matthey.com;**joe.stevenson@matthey.com质子交换膜燃料电池(pemfc)主导着运输燃料电池市场，铂(Pt)是用于阳极和阴极的催化剂材料。本文综述了Pt或其合金在活性、选择性、稳定性和耐毒害性方面的基本原理，这些基本原理使Pt或其合金成为这方面应用的最佳材料。显然，Pt是唯一能够满足性能要求的元素，同时避免反应动力学缓慢，避免过氧化氢(H2O2)形成导致质子交换膜(PEM)系统降解和金属浸出导致催化剂降解。本文还讨论了提高Pt性能的一些方法。
{"title":"The Role of Platinum in Proton Exchange Membrane Fuel Cells","authors":"Oliver T. Holton, J. W. Stevenson","doi":"10.1595/147106713X671222","DOIUrl":"https://doi.org/10.1595/147106713X671222","url":null,"abstract":"Johnson Matthey, Orchard Road, Royston, Hertfordshire SG8 5HE, UK Email: *oliver.holton@matthey.com; **joe.stevenson@matthey.com Proton exchange membrane fuel cells (PEMFCs) dominate the transportation fuel cell market and platinum (Pt) is the catalyst material used for both anode and cathode. This review sets out the fundamentals of activity, selectivity, stability and poisoning resistance which make Pt or its alloys the best available materials to use in this application. It is clear that Pt is the only element which can meet the requirements for performance while avoiding slow reaction kinetics, proton exchange membrane (PEM) system degradation due to hydrogen peroxide (H2O2) formation and catalyst degradation due to metal leaching. Some of the means by which the performance of Pt can be enhanced are also discussed.","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"259-271"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X671222","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1595/147106713X673194
Andrew D. Heavers, Michael Watson, A. Steele, Jeanette Simpson
{"title":"Final Analysis: Platinum Group Metal Catalysts for the Development of New Processes to Biorenewables","authors":"Andrew D. Heavers, Michael Watson, A. Steele, Jeanette Simpson","doi":"10.1595/147106713X673194","DOIUrl":"https://doi.org/10.1595/147106713X673194","url":null,"abstract":"","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"322-325"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X673194","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1595/147106713X672320
M. Picquet
{"title":"Organometallics as Catalysts in the Fine Chemical Industry","authors":"M. Picquet","doi":"10.1595/147106713X672320","DOIUrl":"https://doi.org/10.1595/147106713X672320","url":null,"abstract":"","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"272-280"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X672320","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1595/147106713X671457
J. Cooper, Joel Beecham
Johnson Matthey Emission Control Technologies, Orchard Road, Royston, Hertfordshire SG8 5HE, UK *Email: jonathan.cooper@matthey.com The price differential between platinum and palladium has driven the industry to adopt emissions control catalyst formulations for gasoline engines that contain higher levels of Pd than Pt, and in most cases no Pt. In addition fl uctuations in the price of rhodium have led to thrifting of this metal. This study compares the performance of ten different catalyst compositions with varying ratios of Pt, Pd and Rh for a Euro 5 vehicle and under bench test conditions. The results show that a system with low Rh loading can readily be improved by increasing the Rh loading and there is a relatively large effect of doing this by a small amount. Increasing the Pd or Pt loading also improves emissions performance but by a signifi cantly smaller amount than the effect of changing the Rh loading. Conversely it may be possible to decrease the Pt or Pd loading with only a small effect on emissions. Furthermore it was found that Pd outperforms Pt under most conditions, although not signifi cantly. The difference appears greater under more stressful conditions such as high-speed driving or wide perturbation amplitude.
Johnson Matthey排放控制技术公司，乌节路，罗伊斯顿，赫特福德郡SG8 5HE，英国*电子邮件:jonathan.cooper@matthey.com铂和钯之间的价格差异促使该行业采用汽油发动机排放控制催化剂配方，其中Pd含量高于Pt，在大多数情况下不含Pt。此外，铑价格的波动导致了这种金属的节约。本研究比较了10种不同Pt、Pd和Rh比例的催化剂组合在欧5车辆和台架测试条件下的性能。结果表明，低Rh负荷的系统可以很容易地通过增加Rh负荷来改善，并且通过少量增加Rh负荷会产生相对较大的效果。增加Pd或Pt负载也可以改善发射性能，但其效果明显小于改变Rh负载的效果。相反，减少铂或钯的负载对排放的影响可能很小。此外，Pd在大多数条件下优于Pt，尽管不是很明显。在更紧张的条件下，如高速驾驶或大扰动幅度，这种差异会更大。
{"title":"A Study of Platinum Group Metals in Three-Way Autocatalysts","authors":"J. Cooper, Joel Beecham","doi":"10.1595/147106713X671457","DOIUrl":"https://doi.org/10.1595/147106713X671457","url":null,"abstract":"Johnson Matthey Emission Control Technologies, Orchard Road, Royston, Hertfordshire SG8 5HE, UK *Email: jonathan.cooper@matthey.com The price differential between platinum and palladium has driven the industry to adopt emissions control catalyst formulations for gasoline engines that contain higher levels of Pd than Pt, and in most cases no Pt. In addition fl uctuations in the price of rhodium have led to thrifting of this metal. This study compares the performance of ten different catalyst compositions with varying ratios of Pt, Pd and Rh for a Euro 5 vehicle and under bench test conditions. The results show that a system with low Rh loading can readily be improved by increasing the Rh loading and there is a relatively large effect of doing this by a small amount. Increasing the Pd or Pt loading also improves emissions performance but by a signifi cantly smaller amount than the effect of changing the Rh loading. Conversely it may be possible to decrease the Pt or Pd loading with only a small effect on emissions. Furthermore it was found that Pd outperforms Pt under most conditions, although not signifi cantly. The difference appears greater under more stressful conditions such as high-speed driving or wide perturbation amplitude.","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"281-288"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X671457","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1595/147106713X673202
C. O'Connor
Anglo American Technical Solutions Research, PO Box 106, Crown Mines 2025, South Africa In the fl otation of platinum group minerals (PGMs) it has generally been assumed that they will behave similarly to base metal sulfi des and thus sulfi de reagent regimes are generally used in such fl otation plants. However the tellurides and arsenides of platinum and palladium contribute about 50% of the PGMs present in the Platreef ore, located in the northern limb of the Bushveld Complex of South Africa, and there is evidence of these minerals reporting to the fl otation tailings. The present investigation was aimed at studying the fl otation behaviour of tellurides, arsenides and sulfi des of Pt and Pd and relating these observations to their surface characteristics. Microfl otation, zeta potential determinations, time-of-fl ight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) analyses were used to study the synthesised samples after various treatments. It was shown that in almost all cases the addition of a typical sulfi de collector, sodium isobutyl xanthate (SIBX), increased the recovery of all the Pt and Pd minerals investigated but that the presence of copper sulfate widely used to activate sulfi de minerals caused the recoveries to decrease. These results may question the value of adding copper sulfate in the treatment of Platreef PGM-bearing ore.
{"title":"Investigations into the Recovery of Platinum Group Minerals from the Platreef Ore of the Bushveld Complex of South Africa","authors":"C. O'Connor","doi":"10.1595/147106713X673202","DOIUrl":"https://doi.org/10.1595/147106713X673202","url":null,"abstract":"Anglo American Technical Solutions Research, PO Box 106, Crown Mines 2025, South Africa In the fl otation of platinum group minerals (PGMs) it has generally been assumed that they will behave similarly to base metal sulfi des and thus sulfi de reagent regimes are generally used in such fl otation plants. However the tellurides and arsenides of platinum and palladium contribute about 50% of the PGMs present in the Platreef ore, located in the northern limb of the Bushveld Complex of South Africa, and there is evidence of these minerals reporting to the fl otation tailings. The present investigation was aimed at studying the fl otation behaviour of tellurides, arsenides and sulfi des of Pt and Pd and relating these observations to their surface characteristics. Microfl otation, zeta potential determinations, time-of-fl ight secondary ion mass spectrometry (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) analyses were used to study the synthesised samples after various treatments. It was shown that in almost all cases the addition of a typical sulfi de collector, sodium isobutyl xanthate (SIBX), increased the recovery of all the Pt and Pd minerals investigated but that the presence of copper sulfate widely used to activate sulfi de minerals caused the recoveries to decrease. These results may question the value of adding copper sulfate in the treatment of Platreef PGM-bearing ore.","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"302-310"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X673202","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1595/147106713X672311
J. Board, Jennifer L. Cosman, T. Rantanen, S. Singh, V. Snieckus
Snieckus Innovations, Innovation Park, 945 Princess Street, Kingston, Ontario, K7L 3N6, Canada *Email: victor.snieckus@chem.queensu.ca This review constitutes a detailed but non-exhaustive examination of the directed ortho metallation (DoM)– cross-coupling fusion in its many fl avours. Special attention is paid to the application of the concept of the linked reactions and the synthetic utility that it endows, particularly in the case of one-pot reactions that can greatly increase the ease and effi ciency of the process. Personal experience of particular issues that can arise from these reactions and examples of their solutions are given, as well as illustrations of the rapid access to complex molecules that the technique encourages.
{"title":"The Directed ortho Metallation-Cross- Coupling Fusion: Development and Application in Synthesis","authors":"J. Board, Jennifer L. Cosman, T. Rantanen, S. Singh, V. Snieckus","doi":"10.1595/147106713X672311","DOIUrl":"https://doi.org/10.1595/147106713X672311","url":null,"abstract":"Snieckus Innovations, Innovation Park, 945 Princess Street, Kingston, Ontario, K7L 3N6, Canada *Email: victor.snieckus@chem.queensu.ca This review constitutes a detailed but non-exhaustive examination of the directed ortho metallation (DoM)– cross-coupling fusion in its many fl avours. Special attention is paid to the application of the concept of the linked reactions and the synthetic utility that it endows, particularly in the case of one-pot reactions that can greatly increase the ease and effi ciency of the process. Personal experience of particular issues that can arise from these reactions and examples of their solutions are given, as well as illustrations of the rapid access to complex molecules that the technique encourages.","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"234-258"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X672311","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-10-01DOI: 10.1595/147106713X671871
A. M. Bonastre
{"title":"“Catalysts for Alcohol-Fuelled Direct Oxidation Fuel Cells”","authors":"A. M. Bonastre","doi":"10.1595/147106713X671871","DOIUrl":"https://doi.org/10.1595/147106713X671871","url":null,"abstract":"","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"297-301"},"PeriodicalIF":0.0,"publicationDate":"2013-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X671871","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-07-01DOI: 10.1595/147106713X667632
G. Mishra, Devraj Singh, P. Yadawa, S. Verma, R. Yadav
Department of Physics, University of Allahabad, Allahabad-211002, India In the present study polyvinylpyrrolidone (PVP) stabilised copper/palladium bimetallic nanoclusters were synthesised through chemical routes. The prepared Cu/Pd bimetallic nanoparticles were characterised by ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The UV-vis absorbance band confi rmed the formation of complex metal ions triggered by the complexing agent trisodium citrate. The XRD pattern indicated the formation of bimetallic nanoparticles. The TEM images of the synthesised bimetallic Cu/Pd nanoparticles showed that the size distribution of the particles was in the range 5–15 nm. An acoustic particle sizer was then used to analyse the size distribution. The results obtained by the acoustic particle sizer were consistent with the XRD and TEM analyses. These results demonstrate the potential usefulness of the acoustic particle sizer for quick and easy characterisation of nanoparticles in various catalytic, sensor and fuel cell applications.
{"title":"Study of Copper/Palladium Nanoclusters Using Acoustic Particle Sizer","authors":"G. Mishra, Devraj Singh, P. Yadawa, S. Verma, R. Yadav","doi":"10.1595/147106713X667632","DOIUrl":"https://doi.org/10.1595/147106713X667632","url":null,"abstract":"Department of Physics, University of Allahabad, Allahabad-211002, India In the present study polyvinylpyrrolidone (PVP) stabilised copper/palladium bimetallic nanoclusters were synthesised through chemical routes. The prepared Cu/Pd bimetallic nanoparticles were characterised by ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM). The UV-vis absorbance band confi rmed the formation of complex metal ions triggered by the complexing agent trisodium citrate. The XRD pattern indicated the formation of bimetallic nanoparticles. The TEM images of the synthesised bimetallic Cu/Pd nanoparticles showed that the size distribution of the particles was in the range 5–15 nm. An acoustic particle sizer was then used to analyse the size distribution. The results obtained by the acoustic particle sizer were consistent with the XRD and TEM analyses. These results demonstrate the potential usefulness of the acoustic particle sizer for quick and easy characterisation of nanoparticles in various catalytic, sensor and fuel cell applications.","PeriodicalId":20208,"journal":{"name":"Platinum Metals Review","volume":"57 1","pages":"186-191"},"PeriodicalIF":0.0,"publicationDate":"2013-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1595/147106713X667632","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67346686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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