Abstract:In this study, softwood kraft lignin(KL) was degraded by electrochemical oxidation process under KOH homogeneous alkaline system, using Ti/RuO2-IrO2 and stainless steel as anode and cathode respectively. The degradation products were studied on different categories.The effects of KL concentration, current density, reaction temperature and reaction time on the yield of various products were investigated by orthogonal experiment. The optimum conditions for the electrochemical oxidation degradation of KL under this system were as follows: the concentration of the KL was 40 g/L, current density was 60 mA/cm2, reaction temperature was 80℃, and reaction time was 3 h. Under these conditions, the yields pre kg lignin of various small molecule products were 3.442 g of aromatic aldehyde products, 23.913 g of aromatic acid products, and 0.804 g of the benzene and phenolic products. |