The application of isolated bacterial culture as biological tool for hexavalent chromium removal from tannery industry waste water was investigated. A number of bacteria tolerant to high levels of chromate (>400μgml) were isolated from tannery effluents. These isolates showed varying degree of Cr (VI) reduction under oxic and anoxic conditions at room temperature. Ten isolates were found to be ...

Marine seaweed (Eucheuma sp.) associated strains of Aspergillus flavus and Aspergillus niger were tested for their Cr(VI) tolerance. Both the isolates showed luxuriant growth in different concentrations of Cr(VI), i.e., 25, 50 and 100 ppm. There was no marked variation in the dry weight of control and test isolates, which indicated that both the isolates can tolerate a wide range of hexavalent ...

Cr-B2, a Gram-negative hexavalent chromium [Cr(VI)] reducing bacteria, was isolated from the aerator water of an activated sludge process in the wastewater treatment facility of a dye and pigment based chemical industry. Cr- B2 exhibited a resistance for 1,100 mg/l Cr(VI) and, similarly, resistance against other heavy metal ions such as Ni2+ (800 mg/l), Cu2+ (600 mg/l), Pb2+ (1,100 mg/l), Cd2+ ...

An investigation was carried out to determine the cause of death among 450 masons in Iceland who had been exposed to hexavalent chromium, a trace element in cement. The cohort was defined as all men born between 1905 and 1945 who had, according to the Register of Masons and Stone-cutters, finished vocational training as masons. For deaths occurring between 1951 and 1982 information was obtained...

Functional bionanocomposites based on two layered silicates, the commercial montmorillonite known as Cloisite®Na and a natural bentonite from Algeria, were prepared by intercalation of cationic starch, synthesized with two different degrees of substitution, 0.85 and 0.55. After characterization of the prepared bionanocomposites by XRD and zeta potential measurements, batch studies were conducte...

Theories suggest that rapid microbial growth rates lead to quicker development of metal resistance. We tested these theories by adding hexavalent chromium [Cr(VI)] to soil, sowing Indian mustard (Brassica juncea), and comparing rhizosphere and bulk soil microbial community responses. Four weeks after the initial Cr(VI) application we measured Cr concentration, microbial biomass by fumigation ex...

Introduction Differentiating between the two most frequent oxidation states of chromium is fundamental in speciation studies of this element on account of the toxicity of hexavalent chromium. In fact, most of the works on this element published so far deal solely with this aspect [1]. Flow-injection analysis (FIA) has been used several times for determining this element in one [2 and 3] or in i...

The biosorption of hexavalent chromium from aqueous solutions by Opuntia cladodes and ectodermis from cactus fruits was investigated. Both types of biomass are considered low-cost, natural, and ecofriendly biosorbents. Batch experiments were carried out to determine Cr(VI) biosorption capacity and the efficiency of the biosorption process under different pH, initial Cr(VI) concentration, and so...

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 ...