改性SiO_(2)-Al_(2)O_(3)复合氧化物的结构与性质研究  

Study on structure and properties of modified SiO_(2)-Al_(2)O_(3) composite oxides

作　　者：盖媛媛[1] 李海涛[2] GE Yuanyuan;LI Haitao(Department of Chemical Engineering,Yulin Vocational and Technical College,Yulin 719000,Shaanxi China;Engineering Research Center of Ministry of Education for Fine Chemicals,Shanxi University,Taiyuan 030006,China)

机构地区：[1]榆林职业技术学院化学工程系,陕西榆林719000 [2]山西大学精细化学品工程研究中心,山西太原030006

出　　处：《粘接》2022年第10期1-4,共4页Adhesion

基　　金：国家自然科学基金(项目编号:22075167);榆林市科技计划项目(项目编号:CXY-2020-017-04);榆林市高新区科技计划项目(项目编号:CXY-2020-42)。

摘　　要：采用溶胶-凝胶法分别制备了碱土金属氧化物MgO、过渡金属氧化物ZrO_(2)、稀土金属氧化物CeO_(2)改性的SiO_(2)-Al_(2)O_(3)复合氧化物,通过XRD、N_(2)吸附、NH_(3)-TPD及Py-IR等表征手段考察了助剂MgO、ZrO_(2)和CeO_(2)的引入分别对SiO_(2)-Al_(2)O_(3)复合氧化物结构及性质产生的影响。结果发现,SiO_(2)-Al_(2)O_(3)复合氧化物(SA)改性后的比表面积均显著增加。其中,SA-Mg的孔体积和平均孔径较SA减小,SA-Zr、SA-Ce的孔体积则增大。引入MgO后,SiO_(2)-Al_(2)O_(3)复合氧化物总酸量减少,弱酸中心数量稍有增加,B酸中心比例增加。引入ZrO_(2)后,SiO_(2)-Al_(2)O_(3)复合物表面产生了新的弱酸和中强酸中心,酸量增加明显,同时L酸中心比例大大增加,酸类型由以B酸中心为主转变为以L酸中心为主。CeO_(2)改性后,SiO_(2)-Al_(2)O_(3)复合氧化物总酸量减少,弱酸中心数量增加,L酸中心比例增加,酸类型以L酸中心为主。SiO_(2)-Al_(2)O_(3)composite oxides modified by MgO,ZrO_(2),and CeO_(2)respectively,were prepared using sol-gel method.The effect on the structure and properties of SiO_(2)-Al_(2)O_(3)composite oxides,after respectively adding MgO,ZrO_(2)and CeO_(2),was tested based on X-ray diffraction(XRD),N_(2)adsorption,temperature programmed desorption of NH_(3)(NH_(3)-TPD),and FTIR spectroscopy of adsorbed Pyridine(Py-IR).The experimental results indicate the specific surface area of modified SiO_(2)-Al_(2)O_(3)composite oxides increased significantly.The pore volume and average pore diameter of SA-Mg were smaller than that of SA,while the pore volume of SA-Zr and SA-Ce was larger than that of SA.After the introduction of MgO,the total acid amount of SiO_(2)-Al_(2)O_(3)composite oxides decreased,the weak acid amount increased slightly,and B/L value increased.After introducing ZrO_(2),the weak and moderate acid amount,as well as the total acid amount increased greatly.SA-Zr was dominated by L acid centers.After modification with CeO_(2),the weak acid amount of SiO_(2)-Al_(2)O_(3)composite oxides increased while the total acid amount decreased.SA-Ce was also dominated by L acid centers.

关 键 词：SiO_(2)-Al_(2)O_(3)复合氧化物 溶胶-凝胶法 改性 结构 酸性质 

分 类 号：O648[理学—物理化学] TQ031[理学—化学]