Electroreduction of Some Diazine and Triazine Pesticides at the Dropping Mercury Electrode

摘要: Electroanalytical methods enable determination of electroactive species in nonhomogeneous systems, as limiting currents are little affected by the presence solid and colloidal particles. An example such applications electrochemical studies binding toxic substances, pesticides, on slightly soluble polymers, lignin. To successfully apply polarographic for following free pesticides a slurry lignin, it is first necessary principle to elucidate processes involved. In aqueous buffered solutions electron transfers, which organic compounds participate, majority cases accompanied chemical reactions. nature process, find pH-region given pesticide electroactive, i.e., gives wave current-voltage curve, determine number electrons transferred. Further information obtained from dependences half-wave potentials pH. Such investigations, combined with spectrochemical equilibrium constants identification products formed controlled potential electrolyses, recognition sequence steps. examples presented, reduction ethylenic bond maleic hydrazide (I), reductions azomethine bonds (\( > \)C=NH\( + -\) some diazine triazine acid-base equilibria, covalent addition water C=N double bonds, ring opening. demonstrated elucidation pattern 2-aminopyrimidines (sulfometuron methyl, II), 1,3,5-triazine(hexazinone, III) two 1,2,4-triazines (metamitron, IVa metribuzin, IVb).