We present an ecofriendly hydroxyapatite (HAP) material functionalized with tin (Sn/HAP) for efficient interfacial reduction of Cr(VI) to Cr(III). Tin was deposited on HAP at different concentrations (from 0.2 1.2 mmol/g) using colloidal or clear acid solutions SnCl2. The morphological and structural properties fresh used Sn/HAP samples were determined (N2 adsorption-desorption, transmission el...

A method for the preconcentration and speciation of chromium in seawater was developed. On-line preconcentration and determination were carried out by using inductively coupled plasma atomic emission spectrometry (ICP-AES) with dual mini-columns containing a chelating resin. In this system, Cr(III) was collected on the first column. The effluent containing residual chromium from the first colum...

Hexavalent chromium [Cr(VI)] and ozone are produced in many arc-welding processes. Cr(VI) is formed when welding with chromium-containing alloys and is a suspected carcinogen. Ozone is formed by the action of ultraviolet light from the arc on oxygen and can cause severe irritation to the eyes and mucous membranes. Previous work has demonstrated that reduction of sodium and potassium in manual m...

Lawrence Berkeley Lab scientists have discovered a bacteria that thrives on toxic waste. A Fourier-transform infrared (FTIR) spectromicroscopy beamline (Beamline 1.4.3) was implemented to identify the toxin-devouring microbes. The bacteria detected converts hexavalent chromium (Cr 6+) a widespread industrial contaminant, into a safer, stable compound (Cr 3+). " Basically, the bugs eat the waste...

A chromium resistant bacterial strain KUCr1 exhibiting potential Cr(VI) reducing ability under in vitro aerobic condition is reported. The bacterial strain showed varied degree of resistance to different heavy metals. The MIC of chromium to this strain was found to be 950 mM under aerobic culture condition in complex medium. The factors affecting Cr(VI) reduction by this strain under culture co...

The active centers of carbon catalysts doped with cobalt, nickel, copper, manganese, zinc, and chromium were modeled by density functional theory methods. Likewise, the thermodynamics oxygen reduction reaction (ORR) on model determined. features chemical properties chromium-containing material, namely its spontaneous oxidation into hydroxo form, revealed. In addition, it was established that am...

Common sources of chromium in wastewater are electroplating and leather industries. Hexavalent chromium is more toxic and carcinogenic compared to its trivalent counterpart. Conversion of Cr (VI) to Cr (III) in an aqueous medium both by chemical reduction using zerovalent iron and by photocatalytic reduction using UV radiation and ZnO semiconductor has been investigated using potassium dichroma...

textile wastewater contains substantial pollution loads in terms of chemical oxygen demand (cod), biological oxygen demand (bod), total suspended solids (tss), total dissolved solids (tds) and heavy metals. phytoremediation used for removing heavy metals and other pollutants by aquatic macrophytes treatment systems (amats) is well established environmental protective technique. a lab scale stud...