448 / 2018-09-04 12:52:25

Depolymerization of lignin over CoO/m-SEP catalyst under supercritical methanol

全体主题 > 生物质液体燃料

The sepiolite (SEP) had well-ordered pore structure, affluent surface acidity and excellent hydrothermal stability, and was used as support to load CoO species. The modified SEP (m-SEP) and as-prepared Co/m-SEP catalyst were applied into lignin depolymerization reaction under supercritical methanol. The m-SEP and Co/m-SEP were characterized by N2 adsorption-desorption, powdered X-ray diffraction (XRD) and NH3 temperature programmed desorption (NH3-TPD). The results revealed that Co/m-SEP had appropriate surface acidity and larger pore diameter than that of m-SEP. As expected, Co/m-SEP showed the highest degree of lignin liquefaction (74.25%) and the yield of petroleum ether soluble product (8.18%) as well as the lowest char yield (11.23%) under same reaction conditions. In addition, the effect of reaction temperature on the degradation of lignin was investigated over Co/m-SEP catalyst under supercritical methanol. It found that raising the reaction temperature would promote the lignin depolymerization while excessively high temperature would lead to severe repolymerization.