生物质结渣固体碱催化剂制备生物柴油

采用经气化炉烧结的生物质结渣为固体碱催化剂,催化油脂转化合成生物柴油。对固体碱催化剂进行表征,并考察物质的量之比、反应温度、反应时间和催化剂用量对反应的影响。结果表明：生物质结渣固体碱催化剂主要成分（按质量分数计）为SiO₂（40%~60%）、CaO（10%~20%）、K₂O（10%~15%）、MgO（≤10%）、Al₂O₃（≤8%）、FeO（≤4%）等,碱性位浓度为0.3974 mmol/g,催化剂比表面积为1.266 m²/g,孔径主要集中于5~10 nm。固体碱催化剂在生物柴油制备过程中表现优异,在反应温度200 ℃,甲醇/菜籽油物质的量之比14∶1,催化剂量20%（质量分数,相对于菜籽油质量）,反应8 h条件下,生物柴油转化率达95%以上,该催化剂连续使用33次后,生物柴油转化率保持在85%以上,具有良好可重复利用性。

PREPARATION OF BIODIESEL USING BIOMASS SLAGGING AS SOLID BASE CATALYST

In this study, biomass slagging sintered by gasifier was used as solid base catalyst to catalyze the conversion of oil to biodiesel. The solid base catalyst was characterized, and the effects of molar ratio, reaction temperature, reaction time and catalyst amount on the reaction were investigated. The results show that the main components （calculated as oxides） of biomass slag-forming solid alkali catalyst are： silica （40%-60%,wt）, calcium oxide （10%-20%,wt）, potassium oxide （10%-15%,wt）, magnesium oxide （≤10%,wt）, alumina （≤ 8%,wt）, ferrous oxide （≤4%,wt）, etc. The alkaline concentration is 0.3974 mmol/g, the specific surface area of the catalyst is 1.266 m²/g, and the pore diameter is mainly concentrated in 5-10 nm. Biomass slagging solid alkali catalyst has excellent performance in biodiesel preparation. At the reaction temperature of 200 ℃, the molar ratio of methanol/rapeseed oil is 14∶1, and the catalytic dose is 20%,wt （relative to the mass of rapeseed oil）, reaction time is 8 h, the conversion of biodiesel is more than 95%. After 33 times of continuous use of the catalyst, the biodiesel conversion rate remains above 85% without appreciable loss of catalytic activity, which indicates the catalyst has good reusability. The above study reveals that the biomass slagging sintered catalyst demonstrates promise for producing biodiesel.