Heterogeneous catalysts are promising for the transesterification reaction of vegetable oils to produce biodiesel and have been studied intensively over the last decade. Unlike the homogeneous catalysts, heterogeneous catalysts can be easily separated from reaction mixture and reused for many times. They are environmentally benign and could be easily operated in continuous processes. This revie...

Despite decades of extensive studies, the atomic-scale structure active sites in heterogeneous Ziegler–Natta (ZN) catalysts, one most important processes chemical industry, remains elusive and a matter debate. In present work, ZN catalysts absence ethylene, referred to as dormant sites, is elucidated from magnetic resonance experiments carried out on samples reacted with increasing amounts BCl3...

carbon nanotubes were synthesized over a series of zn-containing fe/alumina catalysts by chemical vapor deposition method at two reaction temperatures of 850 and 950 °c using methane as a carbon source. catalysts were synthesized by keeping fe concentration constant and varying zn concentration to study the effects of zn. the catalysts were characterized using x – ray powder diffraction and n2 ...

h-zsm-5 nano-zeolites were synthesized by hydrothermal method using tetrapropylammonium hydroxide (tpaoh) as a template in the presence of various tpabr concentrations. the effect of different tpabr/tpaoh molar ratios was studied on the catalytic performance of dehydration of methanol to dimethyl ether (dme) in a fixed bed reactor under the same operating conditions (t=300°c, p=1 atm, and whsv=...

The development and improvement of methods for the synthesis environmentally friendly catalysts based on base metals is currently an urgent promising task modern catalysis. Catalysts nanoscale magnetite maghemite have fast adsorption–desorption kinetics high chemical activity. purpose this work to obtain magnetic composites, determine their physicochemical characteristics verify activity in pro...

Catalysts are important to the chemical industry and environmental remediation due to their effective conversion of one chemical into another. Among them, composite catalysts have attracted continuous attention during the past decades. Nowadays, composite catalysts are being used more and more to meet the practical catalytic performance requirements in the chemical industry of high activity, hi...

In recent years, Pillared InterLayered Clays (PILCs) have been widely used in several applications; in particular in adsorption and catalysis. The research interest in this family of solids has increased considerably. Clay minerals provide distinct nanometer-scaled layers and interlayers for engineering them as active catalysts. As such, strategic design and preparation has led to a variety of ...

In this paper, structural, magnetic, optical, and photocatalytic properties of core-shell structure Fe3O4@GO nanoparticles have been compared with Fe3O4 nanoparticles in the degradation of methyl blue and methyl orange. For this purpose, GO nanosheets were wrapped around the APTMS-Fe3O4 nanoparticles and then charact...