【摘要】 在 pH5 0～ 6 2 ,甲醛 -邻苯二甲酸氢钾介质和沸水浴中 ,微量二氧化硫能迅速还原三价铁为二价铁 ,使生成的邻菲啉 -铁 (Ⅱ )红色络合物量增多 ,导致溶液颜色加深 ,据此测定二氧化硫的含量。方法的测定范围为 0～ 10 μg/7 3mL ,检出限为 0 3μg/ 7 3mL。用于测定大气中微量二氧化硫 ,获得了满意的结果更多还原

【Abstract】 The content of sulphur dioxide (SO 2) is determined according to the fact that a ferric ion can be reduced rapidly into a ferrous ion by a trace amount of SO 2,using a medium of formaldehyde potassium biphthalate with a pH of 5.0～6.2 and heating with a boiling water bath,which leads to an increase in the concentration of Fe(Ⅱ) o p phenanthroline red complex and the thickening of the solution color.The measuring range and detection limit of the method are 0～10μg/7.3mL and 0.3μg/7.3mL respectively.Satisfactory results can be obtained when using it to determine SO 2 in air.更多还原