the potential of carbon nanotubes (cnt) supported cobalt catalysts for fischer-tropsch (ft) reaction is shown. using the wet impregnation method cobalt on carbon nanotubes catalysts were prepared with cobalt loading varying from 15 to 45 wt. %. the catalysts are characterized by different methods including: bet physisorption, x-ray diffraction, hydrogen chemisorption, and temperature-programmed...

the interaction of the external donor (propyltrimethoxysilane - ptms) with titanium-magnesium catalysts (tmcs) containing dibutylphthalate (dbp) as internal donor, which were prepared in different ways, was studied by chemical analysis and infrared diffuse reflectance spectroscopy (drifts). the chemical composition of the catalysts after their interaction with heptane solutions of ptms, ptms/al...

1,5-benzodiazepines are regarded as one of the most important classes of heterocyclic compounds as privileged structures and have vast range of applications in the field of medicine and chemistry. they are therefore attractive synthetic targets for organic and medicinal chemist. the current review article mainly covers the multicomponent green chemistry approaches for the synthesis of 1,5-benzo...

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...

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=...

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 ...

This paper reviews various types of heterogeneous acid-base catalysts for fragrances preparation. Catalytic activities of the various types of heterogeneous acid and base catalysts in fragrances preparation, i.e. nonzeolitic, zeolitic, and mesoporous molecular sieves, have been reported. Generally, heterogeneous acid catalysts are more commonly used in fragrance synthesis as compared to heterog...

Catalysts for the oxidation of H2O are an integral component of solar energy to fuel conversion technologies. Although catalysts based on scarce and precious metals have been recognized as efficient catalysts for H2O oxidation, catalysts composed of inexpensive and earth-abundant element(s) are essential for realizing economically viable energy conversion technologies. This Perspective summariz...