Spectrophotometric determination of chromium with diphenylcarbazide after extraction using trioctylamine

Specific extraction of chromium as tetrabutylammonium-chromate and spectrophotometric determination by diphenylcarbazide: speciation of chromium in effluent streams.

A very specific, selective, simple, and inexpensive procedure was developed for the speciation of CrVI and CrIII. This method is based on the quantitative extraction of chromate and CrIII (previously oxidized to CrVI) as a tetrabutylammonium-chromate ion-pair in methyl isobutyl ketone (MIBK), and then back extraction and preconcentration with an acidic diphenylcarbazide (DPC) solution. Back ext...

Catalytic Spectrophotometric Determination of Chromium

chromium(III) up to 100 ng mL−1, and for chromium(VI) up to 200 ng mL−1) were obtained, using the “fixed time” method with detection limits of 4.9 ng mL−1 and 3.8 ng mL−1, respectively. The results suggest that at the reaction conditions chromium(VI) is reduced and chromium(III) is oxidized to an intermediate oxidation state and the catalytic action of chromium is due to the formation of an act...

Extraction - Spectrophotometric Determination of Palladium with Tetrabutyl Ammonium Iodide

A sensitive and selective extraction - spectrophotometric method for the determination of trace amounts of palladium is reported. The method is based on quantitative extraction of brownish tetrabutylammoium tetraiodopalladium (II) ion pair into a small valume of chloroform at pH 1.3-12.0, followed by spectrophotometric measurements. The Beer's law is obeyed over the range 0.02-1.09 <em...

Determination of chromium(VI) in electronics materials using trioctylamine modified carbon paste electrode.

A trioctylamine (TOA) modified carbon paste electrode (TOA/CPE) was firstly utilized to determine Cr(VI) in electronics materials. The effects of preconcentration conditions, that is, TOA amount and accumulation time on Cr(VI) accumulation were examined and the optimum experiment conditions for the determination were identified. A sensitive reduction peak in the stripping voltammogram at -0.45 ...

Selective extraction spectrophotometric determination