DECOLOURIZATION OF DYE-CONTAINING SOLUTIONS BY ELECTROCOAGULATION

In the electrocoagulation of Drimarene Discharge X-3LG(R) (R12S) and S amaron Yellow 4(R) (D05H), the effects of sacrificial anodes, initial pH, rate of stirring and concentrations of dyes on the fraction of dec olourization were tested. The experimental results revealed that the c olour of dyes in the aqueous phase was effectively removed when iron a nd aluminium were used as sacrificial anodes and the concentration of the dyes was less than 100 p.p.m. When the concentration of R12S excee ded 300 p.p.m. iron was a more suitable sacrificial anode for electroc oagulation of R12S than aluminium. For the electrocoagulation of D05H in aqueous solution aluminium as a sacrificial anode was superior to i ron when the concentration of D05H exceeded 300 p.p.m. Using iron as s acrificial anode, the residual concentration fraction of R12S was decr eased below 10% when the initial concentration of R12S and charge pass ed were 500 p.p.m. and 120 C, respectively. The decolourization fracti on of D05H was 99% when aluminium was used as sacrificial anode.