Simultaneous voltammetric determination of Mo(VI) and W(VI) by adsorptive differential pulse stripping method using adaptive neuro-fuzzy inference system

摘要

An adsorptive differential pulse stripping method is proposed for the simultaneous determination of molybdenum and tungsten based on the formation of their complexes with a novel proton transfer compound, [phenH] +[pyzdc]-, containing both pyrazine-2,3-dicarboxylic acid and 1,10-phenanthroline. The optimum experimental conditions were obtained using 0.052 mM [phenH]+[pyzdc]- ligand, pH 3.3, accumulation potential of -0.1 V versus Ag/AgCl, accumulation time of 60 s and scan rate of 33.3 mV/s. An adaptive neuro-fuzzy inference system (ANFIS) was utilized for the analysis of the voltammogram data. The detection limits were 4.0 ng/mL for Mo(VI) and 3.0 ng/mL for W(VI). The influence of potential interfering ions on the determination of molybdenum and tungsten was studied. The procedure was applied to the simultaneous determination of molybdenum and tungsten in some water samples.