화학공학소재연구정보센터
Bioresource Technology, Vol.171, 95-102, 2014
Reductive de-polymerization of kraft lignin for chemicals and fuels using formic acid as an in-situ hydrogen source
In this study, formic acid (FA) was employed as an in-situ hydrogen donor for the reductive de-polymerization of kraft lignin (KL). Under the optimum operating conditions, i.e., 300 degrees C, 1 h, 18.6 wt.% substrate concentration, 50/50 (v/v) water-ethanol medium with FA at a FA-to-lignin mass ratio of 0.7, KL (M-w similar to 10,000 g/mol) was effectively de-polymerized, producing de-polymerized lignin (DL, M-w 1270 g/mol) at a yield of similar to 90 wt.% and <1 wt.% yield of solid residue (SR). The M-W of the DL products decreased with increasing reaction temperature, time and FA-to-lignin mass ratio. The sulfur contents of all DL products were remarkably lower than that in the original KL. It was also demonstrated that FA is a more reactive hydrogen source than external hydrogen for reductive de-polymerization of KL. (C) 2014 Elsevier Ltd. All rights reserved.