超声对SAPO-34分子筛合成的影响

Effects of Ultrasound on SAPO-34 Molecular Sieve Synthesis

为提高SAPO-34分子筛的催化性能,对SAPO-34分子筛晶化原液进行超声辐照处理,研究了超声辐照对SAPO-34分子筛合成的影响。采用XRD、SEM、FT-IR和DTG等表征手段对分子筛样品进行了表征。超声作用后晶体的晶化速率和结晶度有所提高,合成的SAPO-34分子筛样品更纯净,分子筛的晶粒大小分布更均匀,平均粒径明显降低。而且超声处理后分子筛的热稳定性更好。甲醇制烯烃催化反应结果表明,超声处理后合成的SAPO-34分子筛对烯烃的选择性有所提高。

The effects of ultrasound irradiation on SAPO-34 molecular sieve synthesis are investigated for improving its catalytic performance in MTO （Methanol to olefin）. The molecular sieve sam- ples are characterized with XRD, SEM, FT-IR, and DTG techniques. XRD results show that the crystallization rate and the crystallinity of SAPO-34 increase apparently after ultrasound irradiation. SEM results show that the crystal size becomes smaller and the size distribution becomes narrower after ultrasound irradiation. Ultrasonic-wave treatment is effective in improving the thermal stability of SAPO-34 molecular sieve. MTO catalytic reaction shows that the SAPO-34 molecular sieve of smaller crystal size has higher selectivity to ethylene and propylene.