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分别以配合物Pd/PPh3和Ni/PPh3为催化剂,二氯乙烷和乙醇的混合物为介质,非均相催化加氢裂解木质素,产物分为溶解组份和不溶解组份,反应后溶解组份明显增加;当催化剂前体为Ni(OAc)2和NiCl2时,催化活性没有Pd(OAc)2和PdCl2的高;对产物进行粘度测试、热重分析和分子量测定,溶解组份分子量大幅降低;考察反应温度、时间、溶剂、催化剂前体及其用量对催化活性的影响,得到较优化的反应条件:木质素0.5000 g,氯化钯0.0809 g,三苯基膦0.2322 g,温度150℃,时间15 h,介质为1,2-二氯乙烷和乙醇的混合物,体积比为2∶1.
The catalysts Pd / PPh3 and Ni / PPh3 were used as catalysts respectively. The mixture of dichloroethane and ethanol was used as medium to heterogeneously catalyze the hydrocracking of lignin. The product was divided into dissolved and insoluble components, and dissolved after reaction (OAc) 2 and PdCl2 were higher than that of Pd (OAc) 2 and PdCl2 when the catalyst precursors were Ni (OAc) 2 and NiCl2. The viscosity, thermogravimetric analysis and molecular weight of the product were measured. The optimum reaction conditions were as follows: lignin 0.5000 g, palladium chloride 0.0809 g, triphenylphosphine 0.2322 g, temperature 150 ℃ , Time 15 h, the medium is a mixture of 1,2-dichloroethane and ethanol, the volume ratio of 2: 1.