【摘要】 研究了在氨水溶液介质中,以氯化钾溶液为活化剂,痕量钴离子催化过氧化氢氧化溴甲酚紫褪色的指示反应,通过测量590 nm处溶液吸光度的改变,建立了催化动力学光度法测定痕量钴的新方法。在最佳实验条件下,该方法测定钴离子的线性范围为0.00~0.048μg.ml-1,检出限为1.6×10-10g.ml-1。对0.040μg.ml-1Co2+进行10次平行测定的相对标准偏差为3.8%。用于维生素B12中钴的测定,回收率为97.23%。该方法灵敏度高、体系稳定、重现性好。更多还原

【Abstract】 A new catalytic kinetic spectrophotometric method for the determination of trace cobalt（Ⅱ） was studied.The method is based on the cobalt（Ⅱ） catalyzing oxidation of bromocresol purple by hydrogen peroxide in the media of ammonia water using potassium chloride as an activator.The absorbance was measured at 590 nm.Under the optimum conditions,the linear range of determination is 0.00～0.048 μg·ml^-1.The detection limit is 1.6×10^-10 g·ml^-1.The relative standard deviation is 3.8%（n=10,0.040 μg·ml^-1 Co²+）.The method was used to the determination of trace cobalt（Ⅱ） in B₁2.The recovery is 97.23%.更多还原