PS-TEMPO, a polymer-supported 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) was successfully applied as a recyclable, active and selective catalyst for the oxidation of alcohols. Bleach, molecular oxygen and air were successfully used as terminal oxidant under conditions suitable for industrial applications. The intrinsic activity and selectivity of TEMPO for primary alcohols to aldehydes were r...

The cationic ring-opening polymerization reaction of tetrahydrofuran at 20 degrees C was catalyzed by H3PW12O40 x 13 H2O as solid acid catalyst. The effect of the proportions of acetic anhydride and catalyst, reaction time and support on the polymerization reaction was investigated. It has been found that the yield and the viscosity of the polymer depend on the proportion of acetic anhydride, t...

photodegradation of dicamba, an ionizable herbicide, using tio2 supported on hzsm-11 zeolite was investigated. four photocatalysts with different weight percentages (wt%) of tio2 were evaluated: 3%, 10%, 30% and 50%. the effects of the catalyst concentration, the initial ph value and the repeatability of the photocatalytic activity after multiple cycles of reuse were also evaluated. results sho...

Poly (vinylpyridine-N-N-methylenebisacrylamide-acrylicacid) (2-VP-MBAm-AA) was prepared from the reaction of TiO2-methacryloxypropyltrimethoxysilane (TiO2-MAPTMS) with 2-vinylpyridine, methylenbisacrylamide (MBAm) and tert-butyl acrylate (t-BuA). Subsequently (2-VP-MBAm-AA) was reacted with CuI to give the Cu(I) NPs supported onto the above polym...

Poly (vinylpyridine-N-N-methylenebisacrylamide-acrylicacid) (2-VP-MBAm-AA) was prepared from the reaction of TiO2-methacryloxypropyltrimethoxysilane (TiO2-MAPTMS) with 2-vinylpyridine, methylenbisacrylamide (MBAm) and tert-butyl acrylate (t-BuA). Subsequently (2-VP-MBAm-AA) was reacted with CuI to give the Cu(I) NPs supported onto the above polym...

A triethylaluminium(TEAl)-modified Phillips ethylene polymerisation Cr/Ti/SiO2 catalyst has been developed with two distinct active regions positioned respectively in the inner core and outer shell of the catalyst particle. DRIFTS, EPR, UV-Vis-NIR DRS, STXM, SEM-EDX and GPC-IR studies revealed that the catalyst produces simultaneously two different polymers, i.e., low molecular weight linear-ch...

poly(p-n-chlorostyrenesulphonamide) synthesized via direct chlorination of poly[(p-styrene) sulphonamide], can be used for selective chlorination of aromatic compounds. aromatic rings of the anisole, p-xylene, ethylbenzene and toluene are chlorinated with good yields. the polymer can be recovery, rechlorinated and reused several times.

Carbon-supported precious metal catalysts are widely used in heterogeneous catalysis and electrocatalysis, and enhancement of catalyst dispersion and stability by controlling the interfacial structure is highly desired. Here we report a new method to deposit metal oxides and metal nanoparticles on graphene and form stable metal-metal oxide-graphene triple junctions for electrocatalysis applicat...

There is a widespread interest in developing methods to recover homogeneous catalysts, particularly chiral catalysts, from a reaction mixture. The impetus to recover and reuse homogeneous catalysts stems not only from an economic standpoint but also from the need to eliminate contamination of the transition metal catalyst in the product and in the waste streams. The challenge is to recover the ...

The control over both the dispersion and the particle size distribution of supported precious metal nanoparticles used in heterogeneous catalysts is of paramount importance. Here, we demonstrate the successful formation of highly accessible and well dispersed gold−palladium nanoparticles, stabilized with two-dimensional graphene oxide, that itself is dispersed by intercalated titania particles ...