Showing papers on "Catalysis published in 1972"
Book•
30 Jun 1972TL;DR: An overview of Chemical Reaction Engineering is presented, followed by an introduction to Reactor Design, and a discussion of the Dispersion Model.
Abstract: Partial table of contents: Overview of Chemical Reaction Engineering. HOMOGENEOUS REACTIONS IN IDEAL REACTORS. Introduction to Reactor Design. Design for Single Reactions. Design for Parallel Reactions. Potpourri of Multiple Reactions. NON IDEAL FLOW. Compartment Models. The Dispersion Model. The Tank--in--Series Model. REACTIONS CATALYZED BY SOLIDS. Solid Catalyzed Reactions. The Packed Bed Catalytic Reactor. Deactivating Catalysts. HETEROGENEOUS REACTIONS. Fluid--Fluid Reactions: Kinetics. Fluid--Particle Reactions: Design. BIOCHEMICAL REACTIONS. Enzyme Fermentation. Substrate Limiting Microbial Fermentation. Product Limiting Microbial Fermentation. Appendix. Index.
8,257 citations
1,832 citations
TL;DR: In the presence of a nickel catalyst, acetylene decomposed to form carbonaceous solids with filamentary, amorphous, or laminar form as discussed by the authors, and parameters controlling the type of deposit have been established.
1,142 citations
1,093 citations
917 citations
Esso1
TL;DR: In this article, the effect of adding copper to nickel was investigated for the hydrogenolysis of ethane to methane and the dehydrogenation of cyclohexane to benzene over a series of copper-nickel alloys.
585 citations
422 citations
Patent•
06 Dec 1972TL;DR: The method of polymerizing olefinic monomers utilizing a solid catalyst composition comprising a solid catalytic complex and an activator, to the resultant high impact resistant polymers, and the method of making such catalytic complexes was described in this article.
Abstract: The present invention relates to the method of polymerizing olefinic monomers utilizing a solid catalyst composition comprising a solid catalytic complex and an activator, to the resultant high impact resistant polymers, to the method of making such catalytic complex, and to the catalytic complex; said catalytic complex comprising the reaction product of an organic oxygenated compound of a metal of groups Ia, IIa, IIb, IIIb, IVb, VIIa, and VIII of the Periodic Table, an organic oxygenated transition compound of a transition metal of groups IVa, Va, and VIa of the Periodic Table, and an aluminium halide.
390 citations
TL;DR: In this article, it was shown that ruthenium is remarkably promoted by the addition of alkali metal, particularly when supported by active carbon (AC) or alumina.
375 citations
TL;DR: Crushed single crystals of perovskite-like compounds RE1-XPb5MnO3 and RECoO3 compare favorably with commercial platinum catalysts in initial activity and lifetime, and are promising substitutes for platinum in devices for the catalytic treatment of auto exhaust.
Abstract: The perovskite-like compounds RE(1-X)Pb(5)MnO(3) and RECoO(3), where RE (rare earth) is lanthanum, praseodymium, or neodymium, are active catalysts for the oxidation of carbon monoxide. Crushed single crystals of these compounds compare favorably with commercial platinum catalysts in initial activity and lifetime. Therefore, these compounds are promising substitutes for platinum in devices for the catalytic treatment of auto exhaust.
254 citations
Patent•
23 Jun 1972
TL;DR: In this article, a process for the stereoregular polymerization of alpha olefins or mixtures thereof with ethylene conducted in the presence of highly active and stereospecific new catalysts is disclosed.
Abstract: There is disclosed a process for the stereoregular polymerization of alpha olefins or mixtures thereof with ethylene conducted in the presence of highly active and stereospecific new catalysts. The catalysts are obtained from the reaction of a particular Al-alkyl compound which is at least in part in the form of a complex and/or a substitution reaction product with an electron-donor compound free from ester groups of oxygenated organic and inorganic acids, with a supported component characterized by having surface area exceeding certain values or by showing a particular X-rays spectrum and which is obtained by contacting a halogenated Ti compound, preferably in the form of a complex with an electron-donor compound, with a support comprising a Mg or Mn dihalide in an active state. In the catalysts the ratio between the Ti compound expressed in Ti g-atoms and the g-moles of the electron donor compounds is lower than 0.3.
TL;DR: In this article, an efficient direct route to optically active α-amino acids has been achieved by a catalytic asymmetric reduction of α-acylaminoacrylic acids.
Abstract: An efficient direct route to optically active α-amino acids has been achieved by a catalytic asymmetric reduction of α-acylaminoacrylic acids.
TL;DR: In this article, a mixture of styrene and ethylbenzene was formed by alkylation of the methyl group of toluene on Na, K, Rb and Cs exchanged zeolites.
TL;DR: Chromocene deposited on silica supports of high surface area forms a highly active catalyst for polymerization of ethylene as discussed by the authors, which is believed to occur by a coordinated anionic mechanism previously outlined.
Abstract: Chromocene deposited on silica supports of high surface area forms a highly active catalyst for polymerization of ethylene. Polymerization is believed to occur by a coordinated anionic mechanism previously outlined. The catalyst formation step liberates cyclopentadiene and leads to a new divalent chromium species containing a cyclopentadienyl ligand. The catalyst has a very high chain-transfer response to hydrogen which permits facile preparation of a full range of molecular weights. Catalyst activity increases with an increase in silica dehydration temperature, chromium content on silica, and ethylene reaction pressure. The temperature-activity profile is characterized by a maximum near 60°C, presumably caused by a deactivation mechanism involving silica hydroxyl groups. A value of 72 was estimated for the ethylene–propylene reactivity ratio (r1). Linear, highly saturated polymers are normally prepared below 100°C. By contrast with other commercial polyethylenes, the chromocene catalyst produces polyethylenes of relatively narrow molecular weight distribution. Above 100°C, unsaturated, branched polymers or oligomers are formed by a simultaneous polymerization–isomerization process.
TL;DR: In this paper, the equilibria of the decomposition reactions of carbon monoxide and methane were studied in the temperature range 450-700 °C on various nickel catalysts by means of a thermogravimetric apparatus.
TL;DR: The intermediate is a charge transfer complex of reduced enzyme and keto acid and that it participates in catalysis, and is concluded that the pathway for acetate production includes the nonenzymatic reaction of these two substances.
TL;DR: In this article, a cyclopentane-deuterium exchange has been followed on nickel and some nickel-copper alloys in the temperature range 200-430 °K.
TL;DR: In this paper, the kinetics of the carbon monoxide oxidation on a clean Pt (110) crystal were investigated in an ultra-high vacuum system by utilizing Auger electron spectroscopy, low-energy electron diffraction and residual gas analysis.
TL;DR: In this article, a flow method was used to measure hydrogen chemisorption on supported platinum catalysts at ambient temperature, the data were in accord with results obtained by the conventional static method.
TL;DR: In this paper, the product distributions and Arrhenius parameters for the zero-order range have been determined for the dehydration on alumina of a series of primary, secondary, and tertiary aliphatic alcohols and for some alicyclic alcohols.
TL;DR: In this article, the experimental determination of the orders of reaction and deactivation in the nth order rate equation is discussed, which represents the four broad classes of deactivation of catalyst particles: parallel, series, side-by-side and independent.
TL;DR: In this article, the carboxy-group of a series of substituted N-methylmaleamic acids is shown to be remarkably sensitive to the pattern of substitution on the carbon-carbon double bond.
Abstract: The efficiency of intramolecular catalysis of amide hydrolysis by the carboxy-group of a series of substituted N-methylmaleamic acids is remarkably sensitive to the pattern of substitution on the carbon–carbon double bond. A single alkyl group increases the rate of hydrolysis by a factor which increases with its size. A second alkyl substituent has a disproportionately larger effect, which is sharply reduced when the two groups are joined together in a ring. The rates of hydrolysis of a series of dialkyl-N-methylmaleamic acids range over more than ten powers of ten, and the ‘effective concentration’ of the carboxy-group of the most reactive compound studied is greater than 1010M. This amide, dimethyl-N-n-propylmaleamic acid, is converted into the more stable dimethylmaleic anhydride with a half-life of less than 1s at 39 °C below pH 3. The mechanism of catalysis, and the factors responsible for this extremely high reactivity, are discussed.
TL;DR: In this article, the catalytic activities of transition-metal catalysts in methane formation from carbons were investigated at temperatures up to 1050 °C under atmospheric pressure of hydrogen, and it was shown that methane was produced in several stages and the temperature of maximal rate varied from one metal catalyst to another.
TL;DR: In this paper, the rate of hydrogenation of ethylene on PtSiO2 catalysts has been studied between 207 and 371 °K, and no evidence in their work for spillover of hydrogen from the metal to the alumina with enhanced rates of hydrogenated ethylene adsorbed on alumina.