单扫描示波极谱法测定对苯二胺

Determination of P phenylemediamine(PPD) by Linear Sweep Polarogaphy

利用 Ｃｕ２＋ 催化溶解 Ｏ２ 氧化对苯二胺（ Ｐ Ｐ Ｄ） 的化学反应，极谱法检测氧化产物，建立了示波极谱法测定对苯二胺的新方法． 实验表明， 对苯二胺在 ０．０２ｍ ｏｌ／ Ｌ Ｃｕ２＋ － ０．２ｍ ｏｌ／ Ｌ Ｎａ２ Ｈ Ｐ Ｏ４ － ０．１ｍ ｏｌ／ Ｌ Ｋ Ｈ２ Ｐ Ｏ４ 介质中能够产生一灵敏的阴极还原波， 峰电位为 － ０．４４ Ｖ（ｖｓ． Ｓ Ｃ Ｅ），峰电流与对苯二胺的浓度在１０ ～２００ｎｇ／ｍ ｌ范围内有良好的线性关系，检测限为７．０ｎｇ／ｍ ｌ．可应用于低含量工业废水中对苯二胺的测定．

A new method for determining PPD is put forward, that is, oxidizing PPD by O 2 under the catalysis of Cu 2+ , and then determining the oxidized product by linear sweep polarography. A lot of experimental results show that PPD can produce a sensitive cathodic reducing wave in the solution of 0.02mol/L Cu 2+ 0.2mol/L Na 2HPO 4 0.1mol/L KH 4PO 4, and the peak current potential of the wave is -0.44V(VS.SCE). The relationship between the peak current and the concentration of PPD is linear in the range of 10～20ng/ml. The method can be used for determining the low content of PPD in industrial waste water, and its low limit of detecting PPD is 7.0ng/ml.