Micro-mesoporous ZSM-5 zeolites were obtained by the post-treatment of tetrahydroxy ammonium hydroxide(TPAOH) solution with different concentration.The hierarchical pore structure formed during the desilication proces...Micro-mesoporous ZSM-5 zeolites were obtained by the post-treatment of tetrahydroxy ammonium hydroxide(TPAOH) solution with different concentration.The hierarchical pore structure formed during the desilication process facilitates the dispersion of Pt nanoparticles and Pt/ZSM-5 catalysts exhibit rather high catalytic activity for the deep oxidation of various VOCs at low temperature.The catalyst treated with TPAOH of 0.1 mol/L(Pt/ZSM-5(0.1)) shows the lowest degradation temperature(T90%) of 128 and 142℃, respectively for benzene and n-hexane.Compared with the untreated Pt/ZSM-5 catalyst, the abundant mesopores, small Pt particle size and finely dispersed Pt contribute to the superior catalytic activity and stability of the Pt/ZSM-5 catalysts for VOCs removal.More importantly, the existence of H_(2)O in the feed gases hardly affected the activity of Pt/ZSM-5(0.1) catalyst at the low reaction temperature of 128℃, which is very important for VOCs low-temperature removal in the future practical applications.展开更多
调整双季铵盐表面活性剂与单季铵盐表面活性剂的使用量,通过协同晶化的方式合成了高结晶度、高介孔容的薄层ZSM-5沸石。利用XRD、XRF、SEM、TEM、NH3-TPD、低温氮气物理吸脱附以及27Al MAS NMR对沸石样品进行表征,并评价其甲醇制丙烯反...调整双季铵盐表面活性剂与单季铵盐表面活性剂的使用量,通过协同晶化的方式合成了高结晶度、高介孔容的薄层ZSM-5沸石。利用XRD、XRF、SEM、TEM、NH3-TPD、低温氮气物理吸脱附以及27Al MAS NMR对沸石样品进行表征,并评价其甲醇制丙烯反应(MTP)催化性能。结果表明,薄层沸石的b轴厚度随着双季铵盐表面活性剂使用量的减少而增加,适量的单季铵盐表面活性剂的加入可以起到协同晶化的作用,能够有效稳定胶束,从而调控沸石的形貌。优化2种季铵盐表面活性剂的使用量所得薄层ZSM-5沸石的比表面积和介孔孔容都有所增加,在甲醇制丙烯反应中的活性稳定性也得到较大改善。此外,协同晶化的方式减少了双季铵盐表面活性剂的使用,有利于降低薄层ZSM-5沸石的合成成本。展开更多
基金Key Research and Development Plan of Shaanxi Province(2023-YBGY-290)Research Project of Shaanxi Yanchang Petroleum(Group)Co.,Ltd.(No.ycsy2023ky-B-81)。
基金supported by a grant from the National Key Research and Development Program of China (No.2016YFC0204300)the Nature Science Foundation of China (No.21477109)。
文摘Micro-mesoporous ZSM-5 zeolites were obtained by the post-treatment of tetrahydroxy ammonium hydroxide(TPAOH) solution with different concentration.The hierarchical pore structure formed during the desilication process facilitates the dispersion of Pt nanoparticles and Pt/ZSM-5 catalysts exhibit rather high catalytic activity for the deep oxidation of various VOCs at low temperature.The catalyst treated with TPAOH of 0.1 mol/L(Pt/ZSM-5(0.1)) shows the lowest degradation temperature(T90%) of 128 and 142℃, respectively for benzene and n-hexane.Compared with the untreated Pt/ZSM-5 catalyst, the abundant mesopores, small Pt particle size and finely dispersed Pt contribute to the superior catalytic activity and stability of the Pt/ZSM-5 catalysts for VOCs removal.More importantly, the existence of H_(2)O in the feed gases hardly affected the activity of Pt/ZSM-5(0.1) catalyst at the low reaction temperature of 128℃, which is very important for VOCs low-temperature removal in the future practical applications.
文摘调整双季铵盐表面活性剂与单季铵盐表面活性剂的使用量,通过协同晶化的方式合成了高结晶度、高介孔容的薄层ZSM-5沸石。利用XRD、XRF、SEM、TEM、NH3-TPD、低温氮气物理吸脱附以及27Al MAS NMR对沸石样品进行表征,并评价其甲醇制丙烯反应(MTP)催化性能。结果表明,薄层沸石的b轴厚度随着双季铵盐表面活性剂使用量的减少而增加,适量的单季铵盐表面活性剂的加入可以起到协同晶化的作用,能够有效稳定胶束,从而调控沸石的形貌。优化2种季铵盐表面活性剂的使用量所得薄层ZSM-5沸石的比表面积和介孔孔容都有所增加,在甲醇制丙烯反应中的活性稳定性也得到较大改善。此外,协同晶化的方式减少了双季铵盐表面活性剂的使用,有利于降低薄层ZSM-5沸石的合成成本。
