heavy metals in water resource are one of the most important environmental problems of countries. chromium is considered as one of the important environmental pollutants due to its toxicity considered as water contaminant that may disturb metabolic activity. this research aims to study the potential of jujube fruit powder for low cost adsorption of cr (vi) in compression with granular activated...

In this approach, a pneumatic flow injection-tandem spectrometer system, without a delivery pump, has been developed to study chromium speciation. In this system, suction force of pneumatic nebulizer of a flame atomic absorption spectrometer has been used for solution delivery through the manifold. Cr(VI) and total Cr concentrations were determined using UV-Vis and FAAS spectrometers, respectiv...

Chromium-vanadium (Cr-V) bimetallic catalysts are prepared by the introduction of vanadium into the Phillips catalyst which is one of the most significant industrial ethylene polymerization catalysts for tuning the Phillips catalyst performances and improving polyethylene properties. In the present work, titanium species were introduced into the fluorine-modified chromium-vanadium bimetallic ca...

Hexavalent chromium is highly toxic to most living organisms and a known human carcinogen by the inhalation route of exposure. Therefore, treatment of Cr(VI) contaminated wastewater is essential before their discharge to the natural water bodies. Cr(VI) reduction to Cr(III) can be beneficial because a more mobile and more toxic chromium species is converted to a less mobile and less toxic form....

Poly(1,3-thiazol-2-yl methacrylamide-co-4-vinyl pyridine-co-divinylbenzene) was prepared and used as a sorbent for the solid-phase extraction of Cr(VI) ions from aqueous solution. Two forms of chromium showed different exchange capacities at different pH values; Cr(VI) was selectively retained especially at pH 2. The total chromium was determined after the oxidization of Cr(III) to Cr(VI) by po...

chromium is one of the major causes of environmental pollution. to remove heavy metal ions from water, microorganisms can be used. in this study, dead fungal biomass of aspergillus niger is used. the biomass was boiled in 0.5 n naoh solutions to increase the metal removal capacity of a.niger and was applied when the ph of wash solution was in the normal range. the optimum adsorption ph value ob...

* Corresponding author The potential to remove Cr (VI) from aqueous solutions through biosorption using the husk of Bengal gram (Cicer arientinum), was investigated in batch experiments. The results showed removal of 99.9% of chromium in the 10 mgl chromium solution, the biomass required at saturation was 1 g mg. Kinetic experiments revealed that the dilute chromium solutions reached equilibriu...

Reaction of potassium dichromate with sodium ascorbate was studied by EPR spectroscopy at room temperature, in 0.10 M N-[2-hydroxyethyl]piperazine-N'-[2-ethanesulfonic acid] (HEPES), phosphate, cacodylate, and tris(hydroxymethyl)aminomethane hydrochloride (Tris.HCl) buffers at pH 7.0, in the presence of 0.10 M spin trap [5,5-dimethyl-1-pyrroline 1-oxide or 2-methyl-N-(4-pyridinylmethylene)-2-pr...

the present study was carried out to determine the effects of supplementing chromium-methionine(cr-met) on performance and carcass traits in mahabadi goat kids. thirty-two male kids (averageinitial bw of 22 ± 2 kg, 4-5mo) were used in a completely randomized design of four treatments vis.:1) control (with no cr suppl.), 2) 500ug cr suppl., 3) 1000ug cr suppl.and 4) 1500ug cr suppl.as cr-met/ani...

On the basis of the chromogenic reaction of chromium(VI) with 1,5-diphenylcarbohydrazide (DPC) on the surface of Polysorb C-18 beads and the sequential injection renewable surface technique (SI-RST), a highly sensitive reflect spectrophotometric method for the determination of chromium(III) and chromium(VI) was proposed. Considerations of system and flow cell design, and factors that influence ...