in this research, the batch removal of toxic hexavalent chromium ions from wastewater and aqueous solution using dried (bd) sargassum sp. (brown marine algae) and activated carbon (ac) prepared from it was examined. biomass, ph and the initial concentration of cr(vi), adsorption models and kinetic studies were investigated. the experiment was performed in a batch system and theeffect of solutio...

Chromium in the sixth oxidation state may easily penetrate cellular membranes via non-specific sulfate transporters due to its tetrahedral symmetry (high similarity to SO4(2-) and HPO4(2-)). This feature makes chromium a toxic and hazardous pollutant responsible for the deterioration of midland water quality. The aim of the study was to evaluate the capacity of two yeast species - Saccharomyces...

Abstract Two biomass agricultural waste materials; rice husks (RH) and potato peels (PP) were used as precursors for preparation of activated carbons by chemical activation using phosphoric acid adsorption hexavalent chromium [Cr(VI)] from tannery effluents. The prepared husk (RH–AC) peel carbon (PP–AC) characterized Fourier transform infrared spectroscopy, scanning electron microscopy X-ray di...

This contribution deals with the waste from the processes in which raw hide is transformed into leather, as well as with the waste generated during further leather processing and the final waste of leather industry, the worn-out shoes. All this waste, if deposited in the open-air dumps, represents a potential threat to human health, because it contains trivalent chromium (Cr III), which can oxi...

Crown ethers 12-crown-4 (12C4), benzo-15-crown-5 (B15C5), 18-crown-6 (18C6), nitrobenzo-18-crown-6 (NB18C6) dibenzo-18-crown-6 (DB18C6) and dicyclohexyl-18-crown-6 (DC18C6), dissolved in dichloromethane, are able to form oxonium-ion complexes in contact with aqueous sulfuric and hydrochloric acid solutions. This ability allows the transfer of Cr(VI) oxanions from the acid media, through an ...

Hydroponic experiments were performed to exam the dynamic change of endogenous proline in rice seedlings exposed to potassium chromate chromium (VI) or chromium nitrate chromium (III). Although accumulation of both chromium species in rice seedlings was obvious, more chromium was detected in plant tissues of rice seedlings exposed to chromium (III) than those in chromium (VI), majority being in...

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...

A rapid, reliable and accurate method for the determination of hexavalent chromium in Portland cement is developed. The proposed method includes direct spectrophotometric determination of Cr (VI) in Portland cement with 1, 2, 5, 8 Tetrahydroxyanthraquinone, (Quinalizarin, QINZ) at pH 1.5. The European Directive (2003/53/EC) limits the use of cements so that it contains no more than 2 mg·Kg of w...

Fish serum may reflect status of many biochemical processes in the metabolism. Heavy metals may alter serum biochemical parameters in fishes. In this study, the effect of Cr(VI) and Al(III) in fresh water fish I.Punctatus and neutralize these metals by using dead fungal biomass. Activity of serum enzymes AST, ALT, ALP, CPK, LDH and α – amylase in aluminium and chromium exposed fish. The above s...

Arachis hypogea shells (ground nut shells), a lignocellulosic waste biomass, was evaluated for sequestering of Cr(VI) from synthetic wastewater. Arachis hypogea shells (AHS) were used in three different forms, viz.natural (AHSN), immobilized in the form of beads (AHSB), and in the form of activated carbon (AHSC). Batch experiments were performed for the removal of hexavalent chromium. Effects o...