Microcystins (MCs), produced by
blue-green algae, are one of the most common naturally occurring
toxins found in natural environment. The presence of MCs in drinking
water sources poses a great threat to people's health. In this study, the degradation behavior of microcystin-RR on boron-doped
diamond (BDD)
electrode was investigated under galvanostatic conditions. Such parameters as reaction time, supporting
electrolyte and applied current
density were varied in order to determine their effects on this oxidation process. The experimental results revealed the suitability of
electrochemical processes employing BDD
electrode for removing MC-RR from the
solution. However, the efficient removal of MC-RR only occurred in the presence of
sodium chloride that acted as redox mediators and the reaction was mainly affected by the
chloride concentration (c(
NaCl)) and applied current
density (I(appl)). Full and quick removal of 0.50 microg/ml MC-RR in
solution was achieved when the operating conditions of c(
NaCl) and I(appl) were 20mM and 46.3 mA/cm(2), or 35 mM and 18.2 mA/cm(2) respectively. The kinetics for MC-RR degradation followed a pesudo-first order reaction in most cases, indicating the process was under
mass transfer control. As a result of its excellent performance, the BDD technology could be considered as a promising alternative to promote the degradation of MC-RR than chlorination in drinking
water supplies.
