无机铝源合成有序介孔氧化铝的影响因素研究

Influencing factors for ordered mesoporous alumina synthesis from inorganic aluminum source

有序介孔氧化铝具有较大的比表面积、均匀且窄的孔径分布、有序的孔结构等特点,在多相催化反应及吸附分离过程中具有十分重要的应用价值,研究其合成及应用具有重要意义。以廉价的无机铝盐为铝源,结合模板剂,利用溶胶-凝胶法,通过改变模板剂的种类、老化时间和温度等影响因素,制备有序介孔氧化铝。采用多种测试技术对其结构进行表征,探讨不同反应条件对合成有序介孔氧化铝结构的影响规律。结果表明,以二正丙胺为模板剂,在40℃条件下老化48 h,可合成比表面积为324.80 m 2·g^(-1),孔容为0.62 cm 3·g^(-1),平均孔径为6.07 nm的介孔氧化铝,且孔径分布较窄,孔道有序性良好。

Ordered mesoporous alumina has the characteristic of large surface area,uniform and narrow pore distribution,which has very important application value in the processes of multi-phase catalytic reactions and adsorption separations.Therefore,it is significant to study its synthesis and application.In this paper,the ordered mesoporous alumina were prepared by the sol-gel method from some cheap inorganic aluminum salts and the specific template agents.The pore structure and property could be adjusted by changing the type of template agents,aging time and temperature and other important factors.To detect the influencing factors during the preparation on the ordered mesoporous alumina,a series of testing techniques were used to characterize the structures and properties of the alumina.The results show that the mesoporous alumina has specific surface area of 324.80 m 2·g^(-1),pore volume of 0.62 cm 3·g^(-1),and average pore diameter of 6.07 nm when di-n-propylamine is used as template and it is aged at 40℃for 48 h during the preparation.Meanwhile,the pore size distribution is narrow and the pores are well ordered.