The removal of chromium(VI) from an aqueous solution using persimmon gel was examined. The amount of chromium(VI) removed was strongly affected by the pH of the solution, with all chromium(VI) being removed at pH 2 or lower. However, in a solution containing, 15 mg dry weight of immobilized persimmon gel, the amount of removed chromium(VI) decreased as the pH increased. A part of chromium(VI) w...

The use of an inorganic phase in water-in-oil (w/o) microemulsion has recently received considerable attention for preparing metal oxide nanoparticles. This is a technique, which allows preparation of ultrafine metal oxide nanoparticles within the size range 40 to 80 nm. Preparation of nano chromium (III) oxide studied investigated in the inverse microemulsion system. Therefore the nucleation o...

a new simple arid rapid catalytic kinetic method for determination of trace amounts of chromium (110 isdescribed. the method is based on the catalytic effect of chromium (iii) on the reduction of methylene blue byascorbic acid in acidic media. the reaction monitored smectrophotomenically by measuring the decrease ofabsorbance at 664 nm at 25 c. the fixed-time method was used for the first 300 s...

in the present study, an indigenous medicinal plant, tridax procumbens (asteraceae) was used as bioadsorbent for the removal of cr (iii) ions from synthetic wastewater and the method was also applied for real sample analysis. the biosorption of cr (iii) was a two-stage batch reactor process. in the first stage, raw biomaterial was used to the conversion of cr (vi) into cr (iii). the amount of t...

Chromium is an environmentally significant human carcinogen with complicated metabolism and an unknown mechanism of mutagenesis. Chromium(VI) is taken up by cells as the chromate anion and is reduced intracellularly via reactive intermediates to stable Cr(III) species. Chromium(III) forms tight complexes with biological ligands, such as DNA and proteins, which are slow to exchange. In vitro, Cr...

A new kinetic spectrophotometic method for the determination of trace amount Chromium (III) in Teareal samples has been described based on it s the catalytic effect on the oxidations of 1 - ( 2 –PyridylAzo ) - 2 - Naphthol, (PAN), by potassium bromated in sulfuric acid. The reaction is followedspec- trophotometrically by measuring the decrease in the absorbance at 469 nm. Under the optimumcondi...

Chromium has two main valence states: hexavalent chromium (Cr[VI]) and trivalent chromium (Cr[III]). Cr(VI), a well-established human carcinogen, can enter cells by way of a sulfate/phosphate anion-transport system, and then be reduced to lower-valence intermediates consisting of pentavalent chromium (Cr[V]), tetravalent chromium (Cr[IV]) or Cr(III) via cellular reductants. These intermediates ...

Agro-waste materials such as sorghum straw (SS), oats straw (OS) and agave baggasse (AB) contain several functional groups (carboxyl, carbonyl, acetamido, amino, hydroxyl, etc.) which are able to bind heavy metal ions present in aqueous solution. The major advantages of these materials are: low-cost, high efficiency and regeneration. The agro-waste materials studied in this research (water wash...

In this work the possibility of simultaneous spectrophotometric determination of chromium (VI) and iron (III) in alloys with help of the mixed organic reagents (diphenylcarbazide and 1,10-phenanthroline, diphenylcarbazide and sulphosalicylic acid) is studied. We have applied curve fitting method to separate individual signals of chromium (VI) and iron (III) from overlapped absorption spectrum. ...

Agro-waste materials such as oats straw (OS) and agave baggasse (AB) have functional groups which are able to bind metal ions. The agro-waste materials studied in this research (acid washed) were chemically characterized and their chromium sorption and desorption capacity was obtained. HNO3, NaOH and EDTA (at different concentrations and temperatures) were used to regenerate partially saturated...