Efficient removal of gaseous trichloroethylene by continuous feed electro-scrubbing using a new homogeneous heterobimetallic electro-catalyst

Abstract

In this study, a heterometallic complex was subjected to the removal of air-pollutants by mediated electrocatalytic reduction (MER) through electro-scrubbing. This paper reports the specific generation of an electro-catalyst, Cu1+ in Cu2+[Ni2+(CN)4] heterometallic complex, and its catalytic reduction efficiency in the degradation of gaseous trichloroethylene (TCE). The oxidation/reduction potential (ORP) and the UV–visible spectral results revealed Cu1+ formation during the electrolysis of Cu2+[Ni2+(CN)4] in 10MKOH instead of Ni1+. In addition, the electrochemical formation of Cu1+ (1.9mM) while in a heterometallic complex was higher than that of the individual Cu2+ ion (0.47mM). The electro-generated Cu1+[Ni2+(CN)4]1− applied to the removal of gaseous TCE by electro-scrubbing showed almost 100% removal with a gas flow rate of up to 4Lmin−1, which is high enough for use on an industrial scale. In addition, cyclic voltammetry confirmed that TCE removal occurs through MER at a high reaction rate. Both gas and solution phase analyses revealed only CO2 as the final product, confirming that mineralization is possible by MER. The achievement of 823.8mg/day removal of TCE under the given conditions brings the present heterometallic approach in electro-scrubbing to a new level in air-pollutant removal.