【摘要】 研究了在六次甲基四胺 -盐酸缓冲介质 ( pH 5 5 )中 ,痕量铬 催化过氧化氢氧化酸性铬蓝K的褪色反应 ,测得其反应表观活化能为 84 82kJ/mol,据此建立了一种测定痕量铬的新方法。在加入适量EDTA情况下 ,常见离子均不干扰铬的测定。方法检出限为 1× 10 - 3μg/mL ,在 2 5mL溶液中 ,线性范围为 0～ 12 μgCr 。该方法具有灵敏度高、选择性好、线性范围宽等特点 ,用于铁标样中铬的测定 ,结果令人满意更多还原

【Abstract】 A new catalytic spectrophotometric method for determination of trace chromium*& has been developed.The method is based on the catalytic effect of chromium*& on the oxidation of acidic chrome blue K by hydrogen peroxide in （CH₂）₆N₄-HCl buffer solution（pH 5.5）.The apparent activation energy of catalytic reaction is 84.82 kJ/mol.The method has the feature of high sensitivity and selectivity and wide linear range.The linear range for the determination of chromium is 0-12 μg/25 mL and the detection limit is 1×10^-3 μg/mL.Common foreign ions have no interfering effect on the determination of Cr*& by adding an appropriate amount of EDTA.The method has been applied to the determination of trace chromium in the certified reference sample of iron with satisfactory results.更多还原