Electrooxidation as the anaerobic pre-treatment of fats: Oleate conversion using RuO2 and IrO2 based anodes

Electrochemical treatment of oleate using RuO2 and IrO2 type dimensionally stable anodes in alkaline medium was performed to develop a feasible anaerobic pre-treatment of fatty effluents. The results showed that the pre-treated solutions over RuO2 were faster degraded by anaerobic consortium than the raw oleate solutions or the electrolysed solutions using IrO2. In batch experiments carried out with pre-treated solutions over RuO2 (100–500 mg/L), no lag phases were observed before the methane production onset. On the other hand, raw oleate and pre-treated oleate over IrO2 had originated lag phases of 0–140 and 0–210 h, respectively. This study demonstrated that it is advantageous to apply the electrochemical treatment carried out on the RuO2 type DSA in order to achieve a faster biodegradation of lipid-containing effluent and consequently to obtain a faster methane production.