Chromium is generated from several industrial processes. It occurs in different oxidation states, but Cr(III) and Cr(VI) are the most common ones. Cr(VI) is a toxic, soluble environmental contaminant. Some bacteria are able to reduce hexavalent chromium to the insoluble and less toxic Cr(III), and thus chromate bioremediation is of considerable interest. An indigenous chromium-reducing bacteria...

To eliminate hazardous hexavalent chromium from a brass wire-mill waste, hydrogen peroxide was examined In place of chromic acid for pickling, first in bench-scale tests and then in plant tests. Nthough the elimination of chromic acid requires more rigid control of the ~ wastewater treatment operation and increases the zinc content of the waste-treatment effluent, the economic benefit of substi...

With the building wastes contaminated by chromium in Haibei Chemical Plan in China as objects, we studied the contents of total Cr and Cr (VI) of different sizes, analyzed the effect of 6 different washing agents, discussed the removal mechanisms of 6 different washing agents for Cr in various forms, and finally selected applicable washing agent. As per the results, particle size had little imp...

Azo dye and hexavalent chromium are two carcinogenic and toxic pollutants present in industrial wastewater. Zinc oxide nanoparticles can be used for the treatment of these pollutants with solar energy. However the nanoparticles themselves generally have some inherent toxicity for aquatic life. In this work, we have selected Channa punctatus as the model aquatic animal and examined whether the n...

Although electrodeposition of chromium has heen practiced for 75 years, the mechanism is still open to conjecture. Par t of the reason is the complexity of the chemistry ofchromic acidand its existencetnaqueoussolutionin the form of coordinated octahedral complexes. These complexes vary both structurally and kinetically a t different CrO, concentrations. Thechemistryoftriand hexavalent Chromium...

This study proposed an oil palm by-product as a low-cost adsorbent for the removal of hexavalent chromium [Cr (VI)] from aqueous solution. Adsorption of Cr (VI) by sulphuric acid and heat-treated oil palm fibre was conducted using batch tests. The influence of pH, contact time, initial chromium concentration and adsorbent dosage on the removal of Cr (VI) from the solutions was investigated. The...

Here, we report the genome sequence for Leucobacter sp. strain G161 due to its distinct and effective hexavalent chromium reduction under aerobic growth conditions, followed by facultative anaerobic incubation. The draft genome sequence of Leucobacter sp. G161 comprises 3,554,188 bp, with an average G+C content of 65.3%, exhibiting 3,341 protein-coding genes and 55 predicted RNA genes.

Chromium (VI), also known as hexavalent chromium, is the second most stable oxidation state of chromium. Rarely occurring naturally, most chromium (VI) compounds are manufactured (products or by-products). Chromium (VI) can be reduced to the more stable chromium (III) in the presence of reducing agents (e.g. iron) or oxidizable organic matter (OSHA, 2006). Selected chemical and physical propert...

Spectrophotometric method using diphenylcarbazide as a colour developing reagent has been used to analyze the chromium content in tannery effluent located in Bara and Parsa districts of Nepal and Sirsiya River which is an ultimate drainage of these waste water streams. The adsorption of hexavalent chromium from aqueous solution onto formaldehyde treated sawdust and charcoal of sugarcane begasse...