Heterogeneous selective hydrogenation of ethylene carbonate (EC), a key step in indirect conversion of CO2, was realized over a copper chromite nanocatalyst prepared via a hydrothermal method followed by calcination. The selectivities towards methanol (60%) and ethylene glycol (93%) were higher than those achieved over other usual hydrogenation catalysts.

By examining the minor and trace element contents of chromites from three intrusions—the Bushveld Complex (South Africa), Stillwater (USA), Great Dyke (Zimbabwe)—and comparing these chromite compositions with those magmas which they could have formed (komatiites picrites) we conclude that ( i) variations in Ti, V, Sc, Ga across stratigraphy individual layers do not support model magma mixing le...

No genetic link between the two main types of chromitite, stratiform and podiform chromitites, has ever been discussed. These chromitite have very different geological contexts; one is a member layered intrusions, representing fossil magma chambers, in crust, forms pod-like bodies, conduits, upper mantle. Chromite grains contain peculiar polymineralic inclusions derived from Na-bearing hydrous ...

Abstract Drilling related to development of the platinum-group element deposit J-M Reef Stillwater Complex returned samples a rare chromitite seam between anorthosite and norite in discordant anorthositic body. Plagioclase core An concentrations are marginally higher modestly reversely zoned on side (average Ancore = 83·8; average – Anrim –1·1) as compared with 82·5; +1·0). The anorthosites als...

cobalt chromite (cocr2o4) with normal spinel structure, shows catalytic activity for oxidation of unburned methane in the natural gas vehilcles (ngv). in this study, cocr2o4 nanoparticles were synthesized through a conventional co-precipitation technique and investigated for the catalytic combustion of methane. cobalt nitrate hexahydrate, chromium nitrate nonahydrate and ammonia solution (25%) ...

We examined oxygen three-isotope ratios of 48 extraterrestrial chromite (EC) grains extracted from mid-Ordovician sediments from two different locations in Sweden, and one location in south-central China. The ages of the sediments ( 470 Ma) coincide with the breakup event of the L chondrite parent asteroid. Elemental compositions of the chromite grains are generally consistent with their origin...

The paper provides results of a detailed mineralogical study some chromitite ores from two deposits in the Southern Urals Kazakhstan: Almaz-Zhemchuzhina and Geofizicheskoe-VII. It is revealed that main ore minerals are Cr-spinel with high Cr# (Cr/(Cr + Al) = 0.8–0.83), as well serpentine chlorite, replacing primary olivine. Chromium spinel grains contain mineral inclusions, which distributed ra...