Synthesis of molybdenum and tungsten modified composite systems based on bisorbent from rice husk

The article presents results of the synthesis of a new composite material modified with polyvalent metals. Rice husk was chosen as a raw material for obtaining a carrier – a bisorbent consisting of carbon and amorphous silicon oxide. The sorption material was obtained from the products of thermal decomposition of rice husks. Further it was modified with ammonium salts of molybdenum and tungsten: (NH4)6Mo7O24·4H2O and (NH4)2O·12WO3·5H2O in Mo/W ratios: 5/5 wt. %, 10/5 wt. % and reducted by heating in a stream of hydrogen. The registration of the voltammetric curves in the medium of 1-methyl-4-piperidone was carried out in various background electrolytes: 0.2 M Li2SO4, pH = 6.36 and 0.1 M KOH, pH = 13, 2,5·10–2 M K2HPO4 + 2,5·10–2 M NaH2PO4, pH = 6.86. Differential voltammetric curves were analyzed. The electrochemical activity of the obtained modified composites in the potential range from -1.2 V to 0.5 V was determinated. The mechanism of the proceeding electrochemical processes on these modified electrode materials has been studied. The possibility of further use of synthesized composite systems based on bisorbents from the rice husk for the electrochemical reduction of 1-methyl-4-piperidone was shown.