掺杂邻香草醛缩硫代氨基脲的新型石蜡碳糊铬(Ⅲ)离子选择性电极

A new chromium(Ⅲ) ion selective electrode based on carbon paste doped with 2-hydroxy-3-methoxy-benzaldehyde-hydrazine-carbothioamide

以邻香草醛和硫代氨基脲合成的席夫碱邻香草醛缩硫代氨基脲（BH）为中性载体，将其与碳粉混合，以液体石蜡为粘合剂，制备了新型铬（Ⅲ）离子选择性电极。电极对Cr^3＋的能斯特响应浓度范围为4.00×10^-6—1.00×10^-2mol／L，斜率为27.82mV／dec（25℃），检出限为1.20×10^-6mol／L。电极的响应时间小于30s，pH使用范围广（3.2-5.8）。在选定的条件下，考察了10余种离子的干扰情况，并利用该离子选择性电极对工业废水中的Cr^3＋进行了测定。

A sensitive film of carbon paste doped with 2-hydroxy-3-methoxy-benzaldehy-hydrazine-carbothioamide as a carrier was prepared for construction of a Cr（Ⅲ）-selective electrode. The electrode exhibits Nemstian response to Cr（Ⅲ） over a range of 4.00×10^-6-1.00×10^-2mol/L, with a slope of 27.82 mV per decade and a detection limit of 1.26×10^-6mol/L. The response time of the electrode is less than 30 s, and it could be used for 2 weeks success-fully. The potential of this electrode is independent of pH in the range of 3.2-5.8. It also exhibits good selectivity for Cr（Ⅲ） over a wide variety of metal ions. The electrode has been used to determine the chromium contents in the wastewater, and the results are excellent.