Some early transition metal (Ti, V, Cr) complexes of the triphosphorus macrocycle 1,5,9-triethyl-1,5,9-triphosphacyclododecane, [12]aneP3Et3, and related derivatives [12]aneP3R3 (R = Ph, C3H6OMe) have been examined for their reactivity towards ethene and propene. All complexes of the type [12]aneP3Et3MCl3 display moderate catalytic activity in the homogeneous polymerisation of ethene when combi...

We employ a combination of Z-contrast scanning transmission electron microscopy (ZSTEM) and first-principles density-functional calculations to investigate the interaction between metal atoms and cubic alumina catalytic supports. We show that there are two observed La sites at the porous γalumina surface, and that single La atoms do not exhibit a tendency to cluster. Cr behaves very differently...

Hydrogen generation technologies have become increasingly important due to recent attention focusing on fuel cells. The water-gas shift reaction, which is performed in two stages as highand low-temperature shift, is of central significance to produce highpurity hydrogen. Generally, the high-temperature water-gas shift reaction (HTS) is conducted on Fe-Cr catalysts. However, these catalytic syst...

Four chromium based oxo-trinuclear carboxylate complexes were prepared by reacting chromium(III) nitrate nonahydrate with acetic acid and substituted carboxylic acids. They were characterized using infrared spectroscopy (FT-IR). Chromium content of the complexes was determined by titrimetry method. The chromium(III) monochloroacetate complex, [Cr3O(ClCH2COO)6.3H2O]NO3.3H2O in combination with d...

the use of an inorganic phase in water-in-oil (w/o) microemulsion has recently received considerable attention for preparing metal oxide nanoparticles. this is a technique, which allows preparation of ultrafine metal oxide nanoparticles within the size range 40 to 80 nm. preparation of nano chromium (iii) oxide studied investigated in the inverse microemulsion system. therefore the nucleation o...

A new chelating material from mercerized cotton linter was prepared by a reaction with succinic anhydride in the presence of toluene/triethylamine and a 4-dimethylaminopyridine catalyst, followed by reacting with Fe(III) to obtain the final product. The materials were characterized by Fourier transform infrared spectrometry, scanning electron microscopy, and energy dispersive spectrometer; the ...

An effect of promoters such as calcium, aluminium, and potassium oxides and also addition of chromium and manganese on the structure of cobalt catalysts was examined. Studies of the catalytic ammonia decomposition over the cobalt catalysts are presented. The studies of the ammonia decomposition were carried out for various ammonia-hydrogen mixtures in which ammonia concentration varied in the r...

the conversion of the cellulose into 5-hmf would experience three steps, cellulose to glycose, glycose to fructose and fructose to 5-hmf. chloride ion can break down the hydrogen bond in cellucose, chromium can catalyze the isomerization of glycose to fructose, and the high temperature is helpful to cyclohydration of fructose to 5-hmf. in this paper, the sawdust has been directly degraded into ...

In pilot-plant tests, the linolenate content of soybean oil was reduced to less than 1% without increasing the saturates, by hydrogenation to an IV of about 115 with an active copper-chromite catalyst. The linolenate-linoleate selectivity ratio (KLe/KLo ) was from 9 to 12. Several commercial copper-chromite catalysts were used in hydrogenation tests. The activities of four of five commercial ca...

We propose a method to enhance the fuel cell efficiency with the simultaneous removal of toxic heavy metal ions. Carbon monoxide (CO), an intermediate of methanol oxidation that is primarily responsible for Pt catalyst deactivation, can be used as an in-situ reducing agent for hexavalent chromium (Cr (VI)) with reactivating the CO-poisoned Pt catalyst. Using electro-oxidation measurements, the ...