METHOD FOR DETERMINING metals in aqueous solutions and TECHNOLOGICAL plum by stripping voltammetry

摘要

FIELD: chemistry.;SUBSTANCE: method of determining thallium in aqueous solutions or process discharges by stripping voltammetry involves converting thallium (II) to thallium (I) in the solution and performing voltammetric determination. According to the invention, thallium ions are accumulated on a graphite electrode in a stirred solution in the presence of platinum (IV) ions for 60-120 s, followed by recording of ion peaks of selective electrolytic oxidation of thallium from an intermetallic compound Pt_xTl_y with potential sweep rate of 50-100 mV/s at electrolysis potential of minus 1.0 V, and then at minus 0.6 V on a background electrolyte of 1 M HCl; concentration of thallium ions is determined from the height of the anodic peak of thallium on the current versus voltage curve in the potential range from 0.6 V to 0.9 V relative a saturated silver chloride electrode by standard addition method.;EFFECT: invention reduces the limit of thallium content determined from the peak of electrolytic oxidation of thallium from the intermetallic compound Pt_xTl_y, obtained after electrolytic concentration of a binary residue of platinum-thallium on a graphite electrode by stripping voltammetry.;2 ex, 2 dwg, 2 tbl