极谱络合吸附波测定化探样品中有效硼

DETERMINATION OF ACTIVE BORON IN GEOCHEMICAL SAMPLES BY ABSORPTIVE POLAROGRAPHIC COMPLEX WAVE METHOD

化探样品中有效硼的极谱法测定,首先用1∶2盐酸分解试样,在含有0.004％铍试剂Ⅲ和1％EDTA 的醋酸—醋酸钠缓冲溶液中,硼与铍试剂Ⅲ形成电活性络合物并吸附在电极上,络合物中铍试剂Ⅲ在电极上产生吸附波。峰电位为-0.64V(对银电极)。检出限 C_(min)=0.0034μg/ml B,硼的浓度在0.0068—0.5μg/ml 的范围内与波高呈良好的线性关系。该方法操作简单、快速,可用于大批量样品的测试。

A simple and rapid method of polarographic determination of active boron ingeochemical samples is studied in the paper.The sample is dissolved by 1∶2 HCl, in HAc-NaAc buffer solution at pH3.5—4.5,containing 0.004% beryllon Ⅲ and 1% EDTA, complex of boron-beryllon Ⅲis absorbed on the electrode and beryllon Ⅲ produces absorptive wave with the peakpotential at-0.64v(vs Ag electrode)and the detection limit of 0.0034μg/ml B.A linearrelationship exists between the wave height and the concentration of boron in therange of 0.0068—0.5μg/ml.The method is applied to the determination of active boron in geochemical samplesand it can obtain satisfactory results.