【摘要】 在pH4.8的HAc-NaAc缓冲溶液介质中,利用痕量铬(VI)催化H2O2氧化次甲基蓝和罗丹明B褪色的指示反应,通过测量在555nm和665nm下催化体系和非催化体系吸光度的变化,建立双波长双指示剂催化动力学光度分析测定痕量铬(VI)的新方法.方法的线性范围为0.025～1.40μg/25mL,检出限为5.2×10-10g/mL.该法简单、灵敏度高、选择性好,用于废水中痕量铬(VI)的测定,结果满意.更多还原

【Abstract】 A dual-wavelength dual-indicator catalytic kinetic spetrophotometric method for the deter mination of trace chromium was studied.It was based on the catalytic effect of chromium(Ⅵ) on the oxidation of methylene blue and rhoda mine B by hydrogen peroxide in HAc-NaAc buffer medium at pH 4.8.The absorbance of catalytic system and uncatalytic system were measured at 555 nm and 665 nm.Under the optimum conditions,the linear range of the deter mination of trace chromium(Ⅵ) was 0.025～1.40 μg/25 mL.The detection limit was 5.2×10-10 g/mL.The method is simple,high sensitivity and good selectivity.The method was applied to the determination of trace chromium(Ⅵ) in waste water with satisfactory results.更多还原