Carcinogenic heavy metal chromium, in its hexavalent form (Cr(VI)), is spuriously used in various industrial operations because of its hardness and stability and is found in industrial effluents in concentrations much above WHO’s prescribed limit (50 mg/L). Conventional methods for removing toxic chromium ion (by chemical reduction followed by precipitation, ionexchange and adsorption on activa...

background : hexavalent chromium ( cr (vi)) is an important contaminant in surface and groundwater and its removal from contaminated water and wastewater has received interest in recent years. this study aimed to explain the removal process of cr (vi) from aqueous solution using nano hydroxyapatite (n-hap) as an adsorbent material. methods: cr (vi) removal experiments with the prepared n-hap we...

This study describes a simple, rapid method for sensing Cr(vi) using 5-thio-(2-nitrobenzoic acid) modified gold nanoparticles (TNBA-AuNPs) as a remover for Cr(iii) and as a sensor for Cr(vi). We discovered that TNBA-AuNPs were dispersed in the presence of Cr(vi), whereas Cr(iii) induced the aggregation of TNBA-AuNPs. Due to this phenomenon, TNBA-AuNPs can be used as a sorbent material for the r...

Chromium (vi) – tolerant bacterial strains, namely, Bacillus sp., Pseudomonas sp., Escherichia coli and Staphylococcus sp. were isolated from the oxidation ditch of a sewage treatment plant. All the isolates tolerated high concentrations of up to 500 μg/ml chromium (vi) in nutrient broth. The growth responses of the bacterial isolates to different concentrations of chromium (vi) were carried ou...

Background & Aims of the Study: Chromium is widely detected in surface waters and underground waters, which usually appear as Cr(VI), and Cr(III), at sites associated with industrial activities. Cr(VI), in effluent streams with a high level of mobility and notorious mutagenic and carcinogenic toxicity; thus Cr(III) does not have much mobility in soil. So, converting it into less h...

A total of 85 chromate-resistant bacteria were isolated from the rhizosphere of water hyacinth grown in Mariout Lake, Egypt, as well as the sediment and water of this habitat. Only 4 (11%), 2 (8%), and 2 (8%) of isolates from each of the environments, respectively, were able to tolerate 200 mg Cr (VI) L(-1). When these eight isolates were tested for their ability to tolerate other metals or to ...

Biosorption of Cd(II), Ag(I) and Au(III) by cyanobacteria Spirulina platensis, of Au(II)—by Streptomyces spp. 19H, and of Cr(VI) and Cr(III)—by Arthrobacter species was studied by using the dialysis and atomic absorption analysis under various conditions. In particular, the impact of the following parameters on biosorption was studied: pH (for Ag, Cd, Au), living and non-living cells (for Cr), ...

recently, a variety of soils contaminated with heavy metals e.g. cr (vi), have been found in industrial sites. such soil contamination is widely distributed in the world and has now become a serious issue for environment. hexavalent chromium, cr (vi), which is known to be carcinogenic and mutagenic to living organisms, has been utilized for leather tanning, electroplating and in other industrie...