稀土改性SO■/M_xO_y型固体酸催化玉米芯水解性能研究

Study on Hydrolysis Properties of Corncob Catalyzed by Rare Earth Modified SO■/M_xO_y Solid Acid

采用稀土硝酸盐合成了La、Nd、Pr稀土改性SO4^2-/MxOy固体酸,将合成的固体酸用于催化玉米芯水解,探究此类固体酸的催化性能。实验发现SO4^2-/Fe2O3-Al2O3-SiO2-Nd2O3催化效果最佳,进一步通过单因素实验考察了催化剂用量、反应目数、反应温度、反应时间对水解木糖含量的影响。采用响应面分析法对实验进行优化,确定优化条件:在玉米芯粒径0.125mm(目数为120目),催化剂用量为0.03g,反应温度为100℃,反应时间为5h的条件下,Nd改性固体酸催化性能最好,水解得到的木糖含量为19.26%。

Using rare earth nitrate,the SO4^2-/MxOy solid acids modified by rare earth La,Nd,Pr is synthesized.Catalytic hydrolysis of corncob with synthesized solid acid,the catalytic performance of such solid acids is studied.It is found that SO4^2-/Fe2O3-Al2O3-SiO 2-Nd2O3 has the best catalytic effect.The effects of catalyst amount,reaction mesh number,reaction temperature and reaction time on xylose content are further investigated.Optimizing the experiment by response surface analysis,the optimum conditions is defined: catalyst amount is 0.03 g,the particle size is 0.125 mm,reaction temperature is 100 ℃,reaction time is 5 h.Under this condition,Nd modified solid acid has the best catalytic performance,the yield of xylose could reach 19.26%.