Applied Catalysis最新文献_第10页

Effect of binding agent on the catalytic activity and thermal stability of granulated spinel catalysts 结合剂对颗粒状尖晶石催化剂催化活性和热稳定性的影响

Applied Catalysis Pub Date : 1991-10-01 DOI: 10.1016/0166-9834(91)80024-Q

D. Mehandjiev *, V. Zarkov, I. Tsolovsky

引用次数: 3

Carbon monoxide hydrogenation on cobalt/alumina and cobalt/NaX catalysts 钴/氧化铝和钴/NaX催化剂上的一氧化碳加氢反应

Applied Catalysis Pub Date : 1991-10-01 DOI: 10.1016/0166-9834(91)80020-W

Wei-Jye Wang, Yu-Wen Chen *

{"title":"Carbon monoxide hydrogenation on cobalt/alumina and cobalt/NaX catalysts","authors":"Wei-Jye Wang, Yu-Wen Chen *","doi":"10.1016/0166-9834(91)80020-W","DOIUrl":"10.1016/0166-9834(91)80020-W","url":null,"abstract":"<div>The synthesis of hydrocarbons from catalytic hydrogenation of carbon monoxide was investigated over Co/Al2O3 and Co/NaX catalysts at 1 atm, 493–553 K, H2/CO = 2, and gas hourly space velocity (GHSV) = 1200. These catalysts were characterized by hydrogen chemisorption. X-ray diffraction (XRD), and temperature-programmed reduction. The type of support had pronounced effects on the activity and selectivity of cobalt. The results indicated that the cobalt oxide supported on alumina is easier to reduce than that on zeolite X. This is essentially due to strong acidity of the HX and the high dispersion of cobalt. This would result in less active sites for the chemisorption of hydrogen, and would result in a decrease in activity and an increase in the selectivity to alkenes. Significant amounts of 2-butene are observed on Co/NaX catalyst, indicating that the predominant secondary reaction is isomerization rather than oligomerization and cracking reactions. The presence of water in the zeolite may cause a change in the catalytic behavior of the Co/NaX catalyst. The kinetic order of the reaction for Co/Al2O3 is negative to the carbon monoxide partial pressure and positive to the hydrogen partial pressure. The reaction rates for the Co/NaX catalysts are independent of the carbon monoxide partial pressure and become more strongly dependent on the hydrogen partial pressure with positive order. The different kinetics seem to be due to different reaction mechanisms operative on the cobalt surface with different degrees of reduction.</div>","PeriodicalId":8091,"journal":{"name":"Applied Catalysis","volume":"77 1","pages":"Pages 21-36"},"PeriodicalIF":0.0,"publicationDate":"1991-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0166-9834(91)80020-W","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88014509","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}

引用次数: 27

Oxidative dehydrogenation of propane in lithium hydroxide/lithium iodide melts 丙烷在氢氧化锂/碘化锂熔体中的氧化脱氢

Applied Catalysis Pub Date : 1991-10-01 DOI: 10.1016/0166-9834(91)80033-S

Ivar M. Dahl , Knut Grande , Klaus-J. Jens , Erling Rytter , Åse Slagtern *

引用次数: 22

Role of rare-earth oxides and thoria as promoters in precipitated iron-based catalysts for Fischer-Tropsch synthesis 稀土氧化物和钍在沉淀铁基费托合成催化剂中的促进剂作用

Applied Catalysis Pub Date : 1991-10-01 DOI: 10.1016/0166-9834(91)80028-U

Ding-zhu Wang, Xiao-ping Cheng, Zhi-er Huang, Xiu-zhi Wang, Shao-yi Peng

{"title":"Role of rare-earth oxides and thoria as promoters in precipitated iron-based catalysts for Fischer-Tropsch synthesis","authors":"Ding-zhu Wang, Xiao-ping Cheng, Zhi-er Huang, Xiu-zhi Wang, Shao-yi Peng","doi":"10.1016/0166-9834(91)80028-U","DOIUrl":"10.1016/0166-9834(91)80028-U","url":null,"abstract":"<div>The catalytic results in Fischer-Tropsch synthesis indicate that the addition of La, Ce, Nd, Eu and Th oxides to a precipitated iron-based catalyst increases the syngas conversion to hydrocarbon products and shifts the selectivity to the gasoline and middle fractions with significant suppression of both methane and wax formation. Rare-earth (RE) oxides are more effective than thoria, of which Eu2O3 shows a unique promoting effect. The results of catalyst characterization obtained from the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR),carbon monoxide temperature-programmed desorption (TPD), carbon dioxide TPD and temperature-programmed surface reaction (TPSR) measurements demonstrate that the presence of these promoters greatly changes both the bulk structure and surface states of the iron catalyst, especially when promoted with europium. It is found that they increase the dispersion of the iron particles, inhibiting their growth and further reduction due to the formation of a mixed Fe-RE(Th) oxide interface, encourage the adsorption and dissociation of carbon monoxide and decrease the reactivity of the surface carbon species towards hydrogen due to the electronic donation properties brought about by their basicities. These results explain the observed variation in the catalytic performances. Eu2O3 exhibits a unique promoting effect on the catalytic activity and selectivity due to its superior structural and chemical effects.</div>","PeriodicalId":8091,"journal":{"name":"Applied Catalysis","volume":"77 1","pages":"Pages 109-122"},"PeriodicalIF":0.0,"publicationDate":"1991-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0166-9834(91)80028-U","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72771845","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}

引用次数: 19

Catalysis letters 催化的信

Applied Catalysis Pub Date : 1991-10-01 DOI: 10.1016/0166-9834(91)80036-V

R. Burch

引用次数: 0

Tailpiece 附属物

Applied Catalysis Pub Date : 1991-10-01 DOI: 10.1016/0166-9834(91)80041-T

Uncle Toby

引用次数: 0

Improvements to raney copper methanol synthesis catalysts through zinc impregnation 锌浸渍法对雷尼铜甲醇合成催化剂的改进

Applied Catalysis Pub Date : 1991-10-01 DOI: 10.1016/0166-9834(91)80026-S

H. Edward Curry-Hyde *, Mark S. Wainwright, David J. Young