Pub Date : 1994-11-01DOI: 10.1080/01614949408013930
K. Zamaraev, M. I. Khramov, V. Parmon
Abstract Photochemistry is recognized to be important for various physicochemical processes in the atmosphere, such as formation of the ozone layer and smogs, degradation of waste substances, etc. [1]. However, up to the present the emphasis in atmospheric photochemistry has been mainly on the study of photochemical reactions that occur with molecules directly excited by absorption of light quanta. However, the major components and impurities of the earth's atmosphere (such as nitrogen, oxygen, water, carbon dioxide, methane, methane halides, etc.) are totally transparent to most solar radiation. Electronically excited states of these molecules are formed only upon absorption of vacuum ultraviolet light quanta with energy hv ≥ 5 eV (i.e., with wavelength λ ≤ 200 nm). Only a small portion of the energy of solar light is found in this spectral region. In other words, most of the energy of the solar flux cannot participate in such direct photochemical reactions.
{"title":"Possible Impact of Heterogeneous Photocatalysis on the Global Chemistry of the Earth's Atmosphere","authors":"K. Zamaraev, M. I. Khramov, V. Parmon","doi":"10.1080/01614949408013930","DOIUrl":"https://doi.org/10.1080/01614949408013930","url":null,"abstract":"Abstract Photochemistry is recognized to be important for various physicochemical processes in the atmosphere, such as formation of the ozone layer and smogs, degradation of waste substances, etc. [1]. However, up to the present the emphasis in atmospheric photochemistry has been mainly on the study of photochemical reactions that occur with molecules directly excited by absorption of light quanta. However, the major components and impurities of the earth's atmosphere (such as nitrogen, oxygen, water, carbon dioxide, methane, methane halides, etc.) are totally transparent to most solar radiation. Electronically excited states of these molecules are formed only upon absorption of vacuum ultraviolet light quanta with energy hv ≥ 5 eV (i.e., with wavelength λ ≤ 200 nm). Only a small portion of the energy of solar light is found in this spectral region. In other words, most of the energy of the solar flux cannot participate in such direct photochemical reactions.","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"76 1","pages":"617-644"},"PeriodicalIF":10.9,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83302538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-11-01DOI: 10.1080/01614949408013929
A. Cybulski
Abstract Methanol is one of the basic chemicals which is manufactured at an annual rate of over 10 million tons. Plant capacity for methanol rises and can be greatly increased eventually when using methanol as a fuel. One of the potential future uses of methanol is as a peaking fuel in coal gasification combined cycle power stations (e.g., in integrated gasification combined cycle, IGCC). In this application, methanol would be produced from the CO-rich gas during periods of low power demand. This methanol would be burned, if necessary, as an auxiliary fuel in combined-cycles gas turbines during periods of peak power demand. Methanol is a clean-burning fuel with versatile applications. As a combustion fuel, it provides extremely low emissions. Methanol can also be used as a primary transportation fuel or a fuel additive.
{"title":"Liquid-Phase Methanol Synthesis: Catalysts, Mechanism, Kinetics, Chemical Equilibria, Vapor-Liquid Equilibria, and Modeling—A Review","authors":"A. Cybulski","doi":"10.1080/01614949408013929","DOIUrl":"https://doi.org/10.1080/01614949408013929","url":null,"abstract":"Abstract Methanol is one of the basic chemicals which is manufactured at an annual rate of over 10 million tons. Plant capacity for methanol rises and can be greatly increased eventually when using methanol as a fuel. One of the potential future uses of methanol is as a peaking fuel in coal gasification combined cycle power stations (e.g., in integrated gasification combined cycle, IGCC). In this application, methanol would be produced from the CO-rich gas during periods of low power demand. This methanol would be burned, if necessary, as an auxiliary fuel in combined-cycles gas turbines during periods of peak power demand. Methanol is a clean-burning fuel with versatile applications. As a combustion fuel, it provides extremely low emissions. Methanol can also be used as a primary transportation fuel or a fuel additive.","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"351 1","pages":"557-615"},"PeriodicalIF":10.9,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80005945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-08-01DOI: 10.1080/01614949408009470
Zhaolong Zhang, X. Verykios, M. Baerns
Abstract The oxidative coupling of methane (OCM) to higher hydrocarbons may eventually become an interesting alternative for the chemical utilization of natural gas. Extensive studies have been conducted since the works of Keller and Bhasin [l] and of Hinsen and Baerns [2].
{"title":"Effect of electronic properties of catalysts for the oxidative coupling of methane on their selectivity and activity","authors":"Zhaolong Zhang, X. Verykios, M. Baerns","doi":"10.1080/01614949408009470","DOIUrl":"https://doi.org/10.1080/01614949408009470","url":null,"abstract":"Abstract The oxidative coupling of methane (OCM) to higher hydrocarbons may eventually become an interesting alternative for the chemical utilization of natural gas. Extensive studies have been conducted since the works of Keller and Bhasin [l] and of Hinsen and Baerns [2].","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"30 1","pages":"507-556"},"PeriodicalIF":10.9,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83352189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-08-01DOI: 10.1080/01614949408009467
U. Sedran
Abstract The importance of fluid catalytic cracking of hydrocarbons (FCC) as a leading process in the chemical industry has been acknowledged for a long time. Present data on feedstock processing and its overall economical impact confirm such a role [1, 21. Technical, economic, and environmental concerns have played significant roles as driving forces in the research conducted on FCC matters, leading to developments that are identifiable along catalytic cracking chronology (e.g., fluid bed technology, zeolite catalyst introduction, promotor addition, octane boosting).
{"title":"Laboratory Testing of FCC Catalysts and Hydrogen Transfer Properties Evaluation","authors":"U. Sedran","doi":"10.1080/01614949408009467","DOIUrl":"https://doi.org/10.1080/01614949408009467","url":null,"abstract":"Abstract The importance of fluid catalytic cracking of hydrocarbons (FCC) as a leading process in the chemical industry has been acknowledged for a long time. Present data on feedstock processing and its overall economical impact confirm such a role [1, 21. Technical, economic, and environmental concerns have played significant roles as driving forces in the research conducted on FCC matters, leading to developments that are identifiable along catalytic cracking chronology (e.g., fluid bed technology, zeolite catalyst introduction, promotor addition, octane boosting).","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"47 1","pages":"405-431"},"PeriodicalIF":10.9,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83133910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-08-01DOI: 10.1080/01614949408009466
S. Rajadurai
Abstract The concept of structure sensitivity is well established for reactions catalyzed by metals as it has been generally demonstrated by the use of supported metal catalysts exhibiting different particle size [l-71. The con-cept of structure sensitivity in catalysis by metal oxides is considerably less well developed than in catalysis by metals, in spite of the growing number of examples of such reactions. Characterization of oxide catalyst is generally more problematical than that of metal; it is difficult, for example, to titrate the active surface areas of supported oxides by chemisorption techniques. Carboxylic acid decomposition could be used as a probe to establish struc-tural dependence and selectivity on metal oxides. For example, in the case of formic acid decomposition, bimolecular decomposition of two adsorbed formates occurs on a surface with Ti4+ cation of fourfold oxygen coordi-znation while unimolecular decomposition occurs in the case of formates adsorbed on Ti4+ fivefold coordinated c...
{"title":"Pathways for Carboxylic Acid Decomposition on Transition Metal Oxides","authors":"S. Rajadurai","doi":"10.1080/01614949408009466","DOIUrl":"https://doi.org/10.1080/01614949408009466","url":null,"abstract":"Abstract The concept of structure sensitivity is well established for reactions catalyzed by metals as it has been generally demonstrated by the use of supported metal catalysts exhibiting different particle size [l-71. The con-cept of structure sensitivity in catalysis by metal oxides is considerably less well developed than in catalysis by metals, in spite of the growing number of examples of such reactions. Characterization of oxide catalyst is generally more problematical than that of metal; it is difficult, for example, to titrate the active surface areas of supported oxides by chemisorption techniques. Carboxylic acid decomposition could be used as a probe to establish struc-tural dependence and selectivity on metal oxides. For example, in the case of formic acid decomposition, bimolecular decomposition of two adsorbed formates occurs on a surface with Ti4+ cation of fourfold oxygen coordi-znation while unimolecular decomposition occurs in the case of formates adsorbed on Ti4+ fivefold coordinated c...","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"14 1","pages":"385-403"},"PeriodicalIF":10.9,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79010713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-08-01DOI: 10.1080/01614949408009468
M. Shelef, G. Graham
Abstract The catalytic treatment of motor vehicle exhaust gas has been a feature of all passenger cars in the USA since the 1975 model year. It has since been adopted in all the developed countries as the principal means of con-trolling the emissions from vehicles powered by Otto-cycle internal com-bustion engines. These include passenger cars, light trucks, and heavy-duty trucks. Catalysts have been developed for motorcycles and even smaller power plants. The so-called three-way catalyst (TWC) has been in use since the 1979 model year. The name reflects the simultaneous treatment by this catalyst of the two reducing pollutants, carbon monoxide and uncombusted hydrocarbons, and the oxidizing pollutant, oxides of nitrogen.
{"title":"Why Rhodium in Automotive Three-Way Catalysts?","authors":"M. Shelef, G. Graham","doi":"10.1080/01614949408009468","DOIUrl":"https://doi.org/10.1080/01614949408009468","url":null,"abstract":"Abstract The catalytic treatment of motor vehicle exhaust gas has been a feature of all passenger cars in the USA since the 1975 model year. It has since been adopted in all the developed countries as the principal means of con-trolling the emissions from vehicles powered by Otto-cycle internal com-bustion engines. These include passenger cars, light trucks, and heavy-duty trucks. Catalysts have been developed for motorcycles and even smaller power plants. The so-called three-way catalyst (TWC) has been in use since the 1979 model year. The name reflects the simultaneous treatment by this catalyst of the two reducing pollutants, carbon monoxide and uncombusted hydrocarbons, and the oxidizing pollutant, oxides of nitrogen.","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"91 1","pages":"433-457"},"PeriodicalIF":10.9,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75235803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-08-01DOI: 10.1080/01614949408009469
C. Bellefon, P. Fouilloux
Abstract Primary or alkylated amines are important chemicals and intermedi-ates. N-Alkylamines are used without further transformation as surface-active agents. Aliphatic primary diamines polymerize with aliphatic diacids to give linear polyamides which have conquered a large place in textile and mechanical industry [11. Mono- and polyamines are produced by catalytic hydrogenation of the corresponding nitriles [2]. In particular this pathway to hexamethylenediamine has been made easier since the synthesis of adi-ponitrile by hydrocyanation of butadiene was made possible [3]. The spec-ifications for production of amines are often very drastic from the point of view of purity, in particular for the diamines used in the textile industry. Thus the stress is put on selectivity of the reaction and most of industrial processes have a yield approaching stoichiometry. It exists few reviews on reduction of nitriles [4, 51, the literature dealing with this type of reaction being mostly published in patents [6–91, an...
{"title":"Homogeneous and heterogeneous hydrogenation of nitriles in a liquid phase: chemical, mechanistic, and catalytic aspects","authors":"C. Bellefon, P. Fouilloux","doi":"10.1080/01614949408009469","DOIUrl":"https://doi.org/10.1080/01614949408009469","url":null,"abstract":"Abstract Primary or alkylated amines are important chemicals and intermedi-ates. N-Alkylamines are used without further transformation as surface-active agents. Aliphatic primary diamines polymerize with aliphatic diacids to give linear polyamides which have conquered a large place in textile and mechanical industry [11. Mono- and polyamines are produced by catalytic hydrogenation of the corresponding nitriles [2]. In particular this pathway to hexamethylenediamine has been made easier since the synthesis of adi-ponitrile by hydrocyanation of butadiene was made possible [3]. The spec-ifications for production of amines are often very drastic from the point of view of purity, in particular for the diamines used in the textile industry. Thus the stress is put on selectivity of the reaction and most of industrial processes have a yield approaching stoichiometry. It exists few reviews on reduction of nitriles [4, 51, the literature dealing with this type of reaction being mostly published in patents [6–91, an...","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"34 1","pages":"459-506"},"PeriodicalIF":10.9,"publicationDate":"1994-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73176795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-05-01DOI: 10.1080/01614949408013925
A. Cybulski, J. Moulijn
Abstract The use of structured catalysts in the chemical industry has been considered for years. Conventional fixed-bed reactors have some obvious disadvantages such as maldistributions of various kinds (including a nonuniform access of reactants to the catalytic surface), high pressure drop in the bed, etc. Structured catalysts are promising as far as elimination of these setbacks is concerned. Two basic kinds of structured catalysts can be distinguished: Structural packings covered with catalytically active material, similar in design to those used in distillation and absorption columns and/or static mixers. Good examples of catalysts of this kind are those offered by Sulzer, clearly developed by Sulzer column packings and static mixers. As in packed beds, there is an intensive radial convective mass transport over the entire cross-section of these packings. Structural packing catalysts and the reactors containing them are, however, not within the scope of this review. Monolithic catalysts are continuou...
{"title":"Monoliths in Heterogeneous Catalysis","authors":"A. Cybulski, J. Moulijn","doi":"10.1080/01614949408013925","DOIUrl":"https://doi.org/10.1080/01614949408013925","url":null,"abstract":"Abstract The use of structured catalysts in the chemical industry has been considered for years. Conventional fixed-bed reactors have some obvious disadvantages such as maldistributions of various kinds (including a nonuniform access of reactants to the catalytic surface), high pressure drop in the bed, etc. Structured catalysts are promising as far as elimination of these setbacks is concerned. Two basic kinds of structured catalysts can be distinguished: Structural packings covered with catalytically active material, similar in design to those used in distillation and absorption columns and/or static mixers. Good examples of catalysts of this kind are those offered by Sulzer, clearly developed by Sulzer column packings and static mixers. As in packed beds, there is an intensive radial convective mass transport over the entire cross-section of these packings. Structural packing catalysts and the reactors containing them are, however, not within the scope of this review. Monolithic catalysts are continuou...","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"21 1","pages":"179-270"},"PeriodicalIF":10.9,"publicationDate":"1994-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85494507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-05-01DOI: 10.1080/01614949408013926
G. Giannetto, R. Monque, R. Galiasso
Abstract A way to increase the value of LPG cut from petroleum feedstocks is its direct transformation to H2 and aromatic products; these aromatic products, BTX—essentially benzene (B), toluene (T), and C, -aromatics (X)—can be used as raw material for the petrochemical industry or as a blending mixture to enhance the octane number of gasoline. However, these transformations require high temperatures. Thermodynamic data show that the conversion of paraffins into aromatics is favored by increasing the length of the chain, and that aromatics are favored in relation to olefins (Table 1) [1,2]. Whereas aromatization of propane and higher paraffins can be carried out at temperatures lower than 500°C, transformation of ethane, and especially that of methane, requires much higher temperatures. This is experimentally supported by the transformation of various hydrocarbons, at constant temperature and space velocity. For instance, over H-[All-ZSM-5, butane and isobutane react four times faster than propane and 100...
{"title":"Transformation of LPG into Aromatic Hydrocarbons and Hydrogen over Zeolite Catalysts","authors":"G. Giannetto, R. Monque, R. Galiasso","doi":"10.1080/01614949408013926","DOIUrl":"https://doi.org/10.1080/01614949408013926","url":null,"abstract":"Abstract A way to increase the value of LPG cut from petroleum feedstocks is its direct transformation to H2 and aromatic products; these aromatic products, BTX—essentially benzene (B), toluene (T), and C, -aromatics (X)—can be used as raw material for the petrochemical industry or as a blending mixture to enhance the octane number of gasoline. However, these transformations require high temperatures. Thermodynamic data show that the conversion of paraffins into aromatics is favored by increasing the length of the chain, and that aromatics are favored in relation to olefins (Table 1) [1,2]. Whereas aromatization of propane and higher paraffins can be carried out at temperatures lower than 500°C, transformation of ethane, and especially that of methane, requires much higher temperatures. This is experimentally supported by the transformation of various hydrocarbons, at constant temperature and space velocity. For instance, over H-[All-ZSM-5, butane and isobutane react four times faster than propane and 100...","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"7 1","pages":"271-304"},"PeriodicalIF":10.9,"publicationDate":"1994-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76634648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1994-05-01DOI: 10.1080/01614949408013927
G. Saracco, V. Specchia
Abstract A membrane is commonly regarded as a barrier capable of being selectively permeated by some components of a mixture or, at least, of changing the composition of a fluid stream that flows through it due to a certain driving force (a pressure, concentration, or electric potential gradient). Permselectivity is thus considered as the most distinctive property of a membrane.
{"title":"Catalytic inorganic membrane reactors: present experience and future opportunities","authors":"G. Saracco, V. Specchia","doi":"10.1080/01614949408013927","DOIUrl":"https://doi.org/10.1080/01614949408013927","url":null,"abstract":"Abstract A membrane is commonly regarded as a barrier capable of being selectively permeated by some components of a mixture or, at least, of changing the composition of a fluid stream that flows through it due to a certain driving force (a pressure, concentration, or electric potential gradient). Permselectivity is thus considered as the most distinctive property of a membrane.","PeriodicalId":50986,"journal":{"name":"Catalysis Reviews-Science and Engineering","volume":"20 1","pages":"305-384"},"PeriodicalIF":10.9,"publicationDate":"1994-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86149084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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