The catalytic dehydration of glycerol to acrolein is investigated over silica-supported niobia catalysts in a continuous fixed-bed gas-phase reactor. Various supported niobia catalysts are prepared and characterized using surface analysis and spectroscopic methods (XRD, UV–Vis, XPS, N2 adsorption), as well as with ammonia adsorption microcalorimetry. Good results are obtained with initial glyce...

ethylene polymerization was carried out using phillips chromium catalyst based on silica supports such as silicaaerogel, sio2 (grace 643), and titanium modified sio2 (g 643), and the results were compared with othercatalysts based on sio2 (aldrich), sba-15(hex), sba-15(sp) and mcm-41. a combination of tga, dsc, xrd,nitrogen adsorption, sem, icp, ftir and other analyses were used to characterize...

A facile and efficient synthesis of bis(indolyl)methanes derivatives (3a-u) was reported via a condensation reaction of aldehydes and indole in the presence of by silica-supported-3-(triethoxysilyl) propane-1-ammonium chloride catalysis under solvent free conditions. We studied the reaction in different conditions and optimized. The use of just 0.02 g of (silica gel-ammonium salt) is sufficient...

−− The main objective of this work is to study the feasibility of new materials to be used as support for boron-nickel catalysts. Potential support materials such as: silica gel, alumina, hydrothermal modified Perlites and zeolite 4A, were characterized by BET, TPR and DRX. After the addition of Ni and B, their catalytic activity evaluated with the nitrobenzene hydrogenation model reaction. The...

1. Introduction Porous solids with bimodal pore structures are widely used as catalyst supports. Examples are formed bodies, such as tablets, beads, extrudates, and monoliths, of molecular sieves, silica and alumina. The formed bodies are prepared usually by compacting fine micro-or mesoporous particles [1]. As a result, macropores are formed between the agglomerated particles. Recently, cataly...

Spent catalysts are principally solid waste which that coming out from nitrogenous fertilizer industry, during the production of ammonia, resulting in the production of large amount of solid waste containing nickel, which is the spent or deactivated catalysts. These catalysts contain from 12-14% nickel based on the production process in fertilizer industry disposal of spent catalyst is a proble...

A range of catalysts comprising of platinum supported on silica, prepared by an impregnation method, have been studied for the total oxidation of naphthalene, which is a representative Polycyclic Aromatic Hydrocarbon. The influence of platinum loading and calcination temperature on oxidation activity was evaluated. Increasing the platinum loading up to 2.5 wt.% increased the catalyst activity, ...