原位法制备磷钨酸/SBA-15催化剂及其催化性能

Preparation of 12-Tungstophosphoric Acid/SBA-15 Catalyst by In-situ Method and Its Catalytic Performance

摘要:

用原位合成法制备了不同固载量的磷钨酸催化剂HPW/SBA-15，通过FT-IR、TEM、XRD、31P NMR及N2-吸附脱附等手段对催化剂进行表征。结果表明，在低固载量时，原位法制备的催化剂保持了SBA-15材料的长程有序结构，并且随着固载量的提高，孔径、比表面积等均有所下降；固载量达到33.3%时，SBA-15材料的长程有序结构遭到一定的破坏；在载体孔壁中高度分散的磷钨酸仍然保持了Keggin特征结构，且与SBA-15材料的表面羟基存在一定的化学相互作用。对苹果酯合成的催化性能研究表明，HPW/SBA-15催化剂具有很高的催化活性和选择性，且具有较好的重复使用性能。

Abstract:

The different loading catalysts of 12-tungstophosphoric acid/SBA-15 were prepared by in-situ method.The structure and properties of the catalysts were characterized by FT-IR spectroscopy、TEM、X-ray diffraction、31P NMR and N2 adsorption-desorption.The results show that the long range order structure on the SBA-15 material is decreased with the improvement of loading. However, the structure of SBA-15 has certain destruction when loading up to 33.3%. The 12-tungstophoaphoric acid highly dispersed in hole of SBA-15 still keeps the Keggin structure, and has certain chemical interaction with surface hydroxy for SBA-15.The catalytic properties of synthetic fruction show that HPW/SBA-15 catalyst have high catalytic activity and selectivity, and show excellent reusabity.