Various chromium-containing catalysts were tested for the total oxidation of trichloroethylene (TCE) as a model reaction for the catalytic combustion of chlorinated organic pollutants. A spinel-type cobalt chromite (CoCr2O4) among others was proven to be a very promising catalyst showing higher activity and higher CO2 selectivity than traditional alumina supported chromia. Even if both Cr3+ and...

Large amounts of polluted water are often obtained from the chemical process industry, which require a mandatory treatment before being disposed of. Heavy metals are employed as homogeneous catalyst in numerous processes, so that recovering and/or recycling of those metals to the reaction unit is essential. In this study, ultrafiltration is presented as a useful technique to recover heavy metal...

The European Union has banned chromium(VI) compounds in electrical and electronic equipment (EEE), such as chromate conversion coating films. Chromium(III) compounds are not banned. Using Raman spectroscopy without any preparation, we distinguished chromium(VI) oxide from chromium(III) oxide and chromium(III) hydroxide in chromate conversion coating films. Raman bands of chromium(VI) oxide were...

The kidney is the principal route of excretion of the essential trace element chromium. Previous studies suggest that five to 40 percent of plasma chromium (III) is ultrafilterable and that 60 to 95 percent of filtered chromium is reabsorbed in the renal tubule. However, less than five percent of a stable Cr (III)-EDTA chelate is reabsorbed; therefore, this complex has been used to measure glom...

Our aim was to investigate the adverse effects of occupational exposure to trivalent chromium. We measured chromium and iron levels in serum and urine and hemoglobin levels in tannery workers and unexposed persons. We studied three groups of subjects. Group 1 included 15 non-smoking male tannery workers highly exposed to chromium from tanning and retanning departments. Group 2 included 14 non-s...

This account describes our quest for controlling the reactivity of organoiron species, and developing an iron catalyst that can efficiently activate a C–H bond substrate possessing directing group, followed by reaction with nucleophiles (magnesium, zinc, boron, or aluminum reagents), electrophiles (alkyl halides, alkanol derivatives, allyl ethers, alkenes, alkynes, chloroamines), another (heter...

Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (Cr VI). Exposure may occur from natural or industrial sources of chromium. Chromium III is much less toxic than chromium (VI). The respiratory tract is also the major target organ for chromium (III) toxicity, similar to chromium (VI). Chromium (III) is an essential element in...

Chromium-oxyhydroxide (CrxOyHz)-based thin films have previously been shown in photocatalysis and industrial chlorate production to prevent unwanted reduction reactions occur, thereby enhancing the selectivity for hydrogen evolution thus overall process efficiency. Here, a highly reproducible synthesis protocol was developed allow electrodeposition of CrxOyHz-based with controlled thickness ran...

176 chromium-exposed and 30 control subjects were selected for this study. Blood samples (3 ml) were collected for the estimation of chromium. The data on chromium concentration indicated a significant higher level of chromium in the blood of the exposed workers as compared to the control. There was no significant correlation between the mean blood and environmental chromium level. This study s...

Analysis of soil from a specific site in New Jersey indicated a low level of sodium and chromium present as a calcium compound. Chromium was then administered orally to young, mature male rats at a level of 240 micrograms/kg for 14 days as chromium-contaminated soil, as CaCrO4, and as an equimolar mixture of the soil and calcium salts for 14 days. The rats were sacrificed 24 hr after the last d...