Catalyst heterogenization

Hess s law A reaction enthalpy is the sum of the enthalpies of any sequence of reactions (at the same temperature and pressure) into which the overall reaction can be divided, heterogenous alloy See alloy. heterogeneous catalyst See catalyst. heterogeneous equilibrium An equilibrium in which at least one substance is in a different phase from the others. Example AgCI(s) Ag+(aq) + Cl "(aq). heterogeneous mixture A mixture in which the... 

When an aldehyde or a ketone is treated with ammonia or a primary or secondary amine in the presence of hydrogen and a hydrogenation catalyst (heterogeneous or... 

VJhereas the occurrence of 3-state models (or even higher-state models) is reasonable in view of catalyst heterogeneity, the mean deviations obtained in the 2-state and the 3-state models are very similar. Thus, for practical purposes, the 2-state model approximates the copolymer system fairly well. 

OMS materials are also green in that they are heterogeneous catalysts. Heterogeneous catalysts do not leach into the system and are therefore completely recoverable. In addition, doping of OMS materials with iron allows separation of... 

There are two kinds of catalysts. Heterogeneous catalysts are insoluble in the medium in which the reaction is taking place so that reactions of gaseous or liquid reagents occur at the surface, whilst homogeneous catalysts are dissolved in the reaction medium and hence all catalytic sites are available for reaction. Some of the properties of catalysts are collected in Table 1.1, where heterogeneous and homogeneous catalysts are compared. 

Table 34 Water-gas shift rates for a,s-[Rh(CO)2(amme)2]PF6 catalyst heterogenized on P(4-VP)149...

Table 37 Water-gas P(4-VP)159 shift rates for [Rh(COD)(amine)2PF6 catalyst heterogenized on... 

A catalyst is a substance that increases the rate at which a chemical reaction reaches equilibrium. Catalysis is the word used to describe the action of the catalyst. Heterogeneous catalysis describes the enhancement in the rate of a chemical reaction brought about by the presence of an interface between two phases [2],... 

Keywords Catalysis, polymer-supported oxidovanadium (IV) complex, Solid supported catalysts, heterogenized homogeneous catalysts... 

Modified Raney Nickel (MRNi) Catalyst Heterogeneous Enantio-Differentiating (Asymmetric) Catalyst... 

When an aldehyde or a ketone is treated with ammonia or a primary or secondary amine in the presence of hydrogen and a hydrogenation catalyst (heterogeneous or homogeneous), reductive alkylation of ammonia or the amine (or reductive amination of the carbonyl compound) takes place.165 The reaction can formally be regarded as occurring in the following manner (shown for a primary amine), which probably does correspond to the actual sequence of steps 166... 

Reactions in which liquid or gas-phase reactions are catalyzed by solid catalysts (heterogeneous catalysis) often exhibit kinetics that are zero order in the reactant species. Explain why this might be so. 

Pt/Al203 catalyst Heterogeneous dilution of (unpublished results) ... 

---