Determination of Chromium () by Extraction Polarographic Method

[摘要] The extraction-polarographic method applied to the determination of micro amount of chromium (¥µ). Chromium(¥µ) was extracted into methylisobuthylketone(MIBK) layer containing diethyldithiocarbamate(DDTC) as Cr(¥²)-DDTC complex from acetate buffered aqueous, solution of pH 5.4 and the direct current polarogram for the extract was recorded after addition of sodium perchlorate as supporting electrolyte. The reduction current was diffusion controlled. And the half wave potential of this reduction wave was -0.81 volt vs. SCE. The diffusion current was proportional to the chromium concentraticn in aqueous solution in the range of 8¡­160 ppm. And the chromium(¥µ) could be selectively determined in the presence of chromium(¥²), since the chromium(¥²) did not interfere up to twice the amount of chromium(¥µ). Many of other metals such as Mn(¥±), Cu(¥²), Zn(¥±), Mg(¥±), Ni(¥±) and Ag(¥°) were found to have no effect even when present in 1000 times the amount of chromium (¥µ).

[学科分类] 化学（综合）