催化光度法测定城市污泥中微量锰

Determination of trace manganese in municipal sludge by catalytic spectrophotometry

研究了在氨三乙酸(NTA)存在下,痕量锰(Ⅱ)在HAc-NaAc介质中对高碘酸钾氧化亮绿SF的褪色反应有强的催化作用,催化程度与锰(Ⅱ)量在一定范围内线性相关,据此建立了新的测定痕量锰(Ⅱ)分光光度法.结果表明,反应体系的最大吸收波长为650 nm,方法检出限为0.060 μg/L,Mn(Ⅱ)量在0～0.006 mg/L范围内符合比尔定律.本法用于测定城市污泥中微量锰,获得满意结果.

In a weak acid medium（HAc - NaAc buffer solution）, trace manganese catalyzes fading reaction of light green SF oxidized by potassium periodate in the presence of nitrilotriacetic acid,and its fading extent is linear with the concentration of Mn（Ⅱ）. Based on this, a new catalytic spectrophotometric method for determining trace Mn（Ⅱ） is developed. The results show that the maximum absorption wavelength of the complex is at 650 nm and the detection limit of the method is 0. 060 μg/L for Mn（Ⅱ）. Beer＇ s law is obeyed for Mn（Ⅱ） in the range of 0-0. 006 mg/L. The method has been applied to the determination of trace manganese in municipal sludge with satisfactory results.