THE ELECTROCHEMICAL DEGRADATION OF LINEARALKYLBENZENESULFONATE (LAS) ON PLATINUM-ELECTRODE

The electrochemical behaviour of linearalklybenzenesulfonate (LAS) on Pt electrode has been investigated in 0.05 M Na2SO4 and in 0.1 M NaCl at pH = 8 by potentiokinetic method and by electrolysis. The anodic an d cathodic semilogarithmic current-potential curves were obtained betw een -1.6 V - +1.6 V. The experimental discharge potentials (Eexp.) hav e been determined by means of current-potential curves obtained by ele ctrolysis method between 0-3 V. The percentages of surface active mate rial remaining in solution after specified time periods (0-6 h) were d etermined for different initial concentrations of LAS (30, 150; 300 pp m) by using the potentiostat (+ 1.6 V) and by applying constant potent ials of 20 V via a direct current source. The concentrations of LAS in solution was determined by UV spectrophometer. Results indicate that when a potential of 20 V is applied on the electrodes the concentratio ns of surface active materials (LAS) decreases by 40-50% at the end of 6h in 0.05 M Na2SO4 solution. (C) 1998 Elsevier Science Ltd. All righ ts reserved.