玉米秸秆酶解木质素及麦草甲酸木质素在钙钛矿催化体系下催化活性比较

Comparison on catalytic activity between enzyme lignin from cornstalk and formic acid hydrolysis lignin from wheat straw in perovskite-type oxide catalyst system

考察了玉米秸秆高温爆破法制浆酶解木质素(EL)以及麦草甲酸木质素(SL)在LaMn0.8Cu0.2O3催化体系下催化湿法氧化为芳香醛反应中的活性差异。结果表明:该催化剂对麦草甲酸木质素的对羟基苯甲醛、香草醛、紫丁香醛的最大得率分别提高33%、65%、48%,最大得率分别达到0.56%、2.97%、4.91%;而玉米秸秆酶解木质素分别相应提高85%、57%、208%,最大得率分别达到2.90%、5.07%、14.6%。同时发现麦草甲酸木质素无论在无催化反应还是该催化体系下各芳香醛的得率均远低于玉米秸秆酶解木质素,其原因是麦草甲酸木质素发生了严重缩合,而玉米秸秆酶解木质素接近原始木质素,未发生缩合反应。

bstract： The difference in catalytic activity between enzyme lignin from explosive pulping of cornstalk steam and formic acid hydrolysis lignin from wheat straw in perovskite-type oxide catalyst system was investigated. The results indicate that the maximum yield of p-hydroxybenzaldehyde, vanillin and syringaldehyde for lignin from wheat straw formic pulping is increased by 33%, 65% and 48%, reaching 0.56%, 2.97% and 4.91% respectively; while the yield for enzymolysis lignin in explosive pulping of cornstalk steam is increased by 85%, 57% and 208%, reaching 2.90%, 5.07% and 14.6% correspondingly. It was found that the yield for tignin from formic pulping is much lower than that of enzyme lignin from explosive pulping of cornstalk steam whether under catalytic reaction or not, this was because more condensation of lignin occurred in wheat straw formic pulping than in cornstalk enzymolysis pulping, which is close to virgin lignin.