固体超强酸SO2-4/ZrO2的制备及其催化性能研究

以氧氯化锆为锆原,氨水为沉淀剂,硫酸溶液为浸渍液,通过沉淀-浸渍法制备SO2-4/ZrO2(SZ)酯化催化剂,其结构经BET、X-射线衍射(XRD)、傅立叶变换红外光谱(FT-IR)及扫描电子显微镜(SEM)表征.结果表明:随着焙烧温度升高,催化剂的比表面积依次降低,孔径增大,氧化锆的晶态由无定形态转化为四方晶态再转化为单斜晶态;于600℃焙烧时,催化剂形成的S=O键红外吸收峰最强;于700℃焙烧时,催化剂结构被破坏.在丙烯酸与十八醇的酯化反应中对催化剂进行活性测试.结果表明:600℃焙烧的催化剂产率最高(96.4%).

Preparation and Catalytic Performance Research of SO2-4 /ZrO2 Solid Superacid Catalyst

The SO2-4 /ZrO2 ( SZ) esterification catalysts were prepared by precipitation-impregnation method using zirconium oxychloride as zirconium , ammonia as precipitant and sulfuric acid solution as impregnation solution .The structures were characterized by BET , X-ray diffraction ( XRD ) , Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM).The results showed that the specific surface area of the catalyst decreased , and the pore size of the zirconia changed from amorphous to tetragonal and then converted into monoclinic with increasing of the calcination tempera -ture.The catalysts calcined at 600 ℃formed the strongest S =O bond infrared absorption peak .The solid super acid structure could be seriously damaged when calcined at 700 ℃.The catalytic perform-ance in the esterification reaction of acrylic acid with stearyl alcohol were investigated .The results showed that the yield was 96 .4%for the catalyst calcined at 600 ℃.