硫酸改性Ti-MCM-41分子筛催化水解纤维素

以硫酸钛为钛源，硅酸钠为硅源，十六烷基三甲基溴化铵为模版剂，采用水热晶化法合成出Ti-MCM-41介孔分子筛，用浸渍法得到硫酸改性Ti-MCM-41分子筛。采用XRD和BET对硫酸改性Ti-MCM-41分子筛进行结构表征，结果发现，Ti-MCM-41分子筛经硫酸改性后仍然具有规则有序的介孔结构和较大的比表面积（604．84m^2／g）。用硫酸改性Ti-MCM-41分子筛催化纤维素水解并探讨了反应温度、反应时间、催化剂用量及液固比对纤维素水解的影响。实验结果表明，硫酸改性Ti—MCM．41分子筛能够明显降低纤维素的残渣率，提高总还原糖和5-羟甲基糠醛（5-HMF）的收率；最佳的反应条件是：反应温度230℃，反应时间15min，催化剂加入量为纤维素／催化剂质量比2：0.3，液固比30，此条件下残渣率为11．95％，总还原糖收率为47．23％，5-HMF收率为20．70％。

The Hydrolysis of Cellulose Catalyzed by H2SO4/Ti-MCM-41

Ti-MCM-41 mesoporous molecular sieve was synthesized by hydrothermal crystalline method using cetyltrimethylammonium bromide as structural template, sodium silicate as silica source and Ti（SO4）2 as titanium source. H2SO4/Ti-MCM-41 was synthesized by impregnation and its structure was characterized by XRD and BET. And the results show that H2SO4/Ti-MCM-41 mesoporous molecular sieve still possesses regular and well-defined mesoporous structures and high specific surface area （604.84 m^2/g）. The hydrolysis of cellulose catalyzed by H2SO4/ Ti-MCM-41 is studied, and the effects of reaction conditions including different reaction temperature, reaction time, catalyst dosages and liquid/solid ratios on the hydrolysis of cellulose are investigated. Results show that H2SO4/Ti-MCM-41 mesoporous molecular sieve can obviously lower the residue ratio and improve the yields of the total sugar and 5-hydroxymethyl furfural. Moreover, the optional conditions were 230℃ of reaction temperature, 15 min of reaction time, mass ratio of cellulose/catalyst 2 ： 0.3 and 30 of liquid/solid. Under the optional conditions, the residue ratio, the yield of total sugar and the yield of 5-hydroxymethyl furfural can reach 11.95%, 47.23%, 20.70%, respectively.