萃取光度法测定微量铜(Ⅱ)的研究

Studies and Application of the Chromogenic Reaction of Cu(Ⅱ) with a New Reagent Piperidine Dithiocarbamate Piperidine

研究了哌啶荒酸哌啶 (PDPC)与Cu(Ⅱ )最佳显色反应的条件 ,在pH =8.5的条件下 ,Cu(Ⅱ )与PDPC形成稳定的黄棕色络合物 ,络合物组成比为M∶R =1∶2 ,最大吸收波长λmax=4 40nm ,表观摩尔吸光系数ε=2 .86×1 0 4 L·mol- 1·cm- 1。该体系显色速度快 ,稳定性好 ,并有较好的选择性 ,应用拟定方法测定合成水样中Cu(Ⅱ )含量 ,结果满意。

Piperidine dithiocarbamate piperidine (PDPC) is a new colour reagent for the determination of Cu(Ⅱ) at pH=8.5. The apparent molar absorptivity is 2.86×10 4 L·mol -1 ·cm -1 for Cu(Ⅱ)-complex (M∶R=1∶2) at 440 nm.In the presence of the masking ageuts such as tartrate and EDTA the color reaction has good selectivity.The method is applied to determine trace Cu(Ⅱ) in synthetical water sample with satisfactory results.