Functional catalyst molar ratio, effects

The investigation of the chemical modification of dextran to determine the importance of various reaction parameters that may eventually allow the controlled synthesis of dextran-modified materials has began. The initial parameter chosen was reactant molar ratio, since this reaction variable has previously been found to greatly influence other interfacial condensations. Phase transfer catalysts, PTC s, have been successfully employed in the synthesis of various metal-containing polyethers and polyamines (for instance 26). Thus, the effect of various PTC s was also studied as a function of reactant molar ratio. 

The halophosphite ligands show the same relationship between activity and the preference for the more linear aldehyde isomer as a function of ligand concentration. A series of bench unit studies utilizing halophosphite catalysts were conducted in which propylene was allowed to react to form butyraldehyde. Table 1 presents bench unit data on the effects of the ligand to rhodium molar ratios. 

In this work the effect of process parameters on the amination of iBuOH to (iBu)2NH was studied over V-modified Raney nickel. V is known to increase the yield of amines and the stability of catalyst (4,5). Factorial experimental design was used to describe the conversion of alcohol, and the yield and selectivity of secondary amine as a function of reaction temperature, space velocity and NH3/iBuOH molar ratio. 

Numerical application. This application concerns the conversion of one reactant by an esterification reaction occurring in a discontinuous and stirred reactor. It is a function of the temperature (factor A), the alcohol-acid molar ratio (factor B), the reaction time (factor C) and the catalyst concentration (factor D). A CFE 2 plan is used to investigate the different effects of the factors. The levels of the factors have been established in order to obtain a good reactant conversion. These levels are temperatures Aj = 110 °C, A2 = 130 °C alcohol-acid molar ratio Bj =... 

All the experiments were conducted with the same amount of active metal (0.54 mg Pd) at 40 °C and at a H2-partial pressure of SOOmmHg. The molar ratio of Pd to the substrate was 1 2070. It was shown that catalysts, the functional groups of which decreased the retention time of the substrate in the polymer matrix or enhanced the substrate solubility in the polymer matrix, catalyzed the hydrogenation of styrene more effectively. Such catalyst types included Jt-acceptor or hydrophobic supports. During the hydrogenation of allyl acrylate of the polar substrate model, the catalytic activity depended on both the -acceptor and polar properties of the polymeric supports. Thus, a definite relationship was determined between properties of functional groups and the respective polymers. 

In monolith febrication it is required to take into account the influence of the precursor gradient chemical composition on the sol-gel process. Parameters that affect the process are metal alkoxide precursor types, pH effect - type of catalyst used, H2O Si molar ratio (/ ), steric effect of precursor ligand groups, and functionality of organically modified silanes (ORMOSIL). 

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