Cu改性SAPO-34分子筛催化CO_(2)环加成反应

Cu-modified SAPO-34 zeolite catalyzed CO_(2) cycloaddition reaction

针对硅铝磷分子筛(SAPO-34)酸性较弱的问题,围绕SAPO-34分子筛的酸性调控开展研究工作,通过将金属Cu原子引入分子筛骨架中,扰动SAPO-34分子筛的酸性位点的分布,获得含高酸量的分子筛催化剂。采用一步水热法,使Cu原位生长入SAPO-34分子筛骨架中。BET、XRD以及UV-vis等结构表征结果表明,Cu原子成功掺入SAPO-34分子筛中。由酸性定量结果,随着Cu添加量的增加,CuAPSO-34分子筛的酸量先增大后减小。利用CO_(2)环加成反应对CuAPSO-34分子筛的催化性能进行评价,在最优的反应条件下,氧化苯乙烯的转化率达到42%。由于Cu改性后产生总酸量提高,其性能优于改性前的SAPO-34分子筛。

This work focuses on the acidity of SAPO-34 zeolite by introducing Cu atoms into the zeolite framework to break the original thermodynamic constraints and perturb the distribution of acidic sites in SAPO-34.A one-step hydrothermal method was employed to incorporate Cu into the SAPO-34 zeolite.The textural characterization such as BET,XRD and UV-Vis showed that Cu atoms were successfully doped into the SAPO-34 framework.Based on the quantification of acid site,the acid amount of CuAPSO-34 increases and then decreases with the increase of Cu addition.The catalytic performance of CuAPSO-34 was evaluated using the CO_(2) cycloaddition reaction,and the conversion of styrene carbonate reached 42%under the optimal reaction conditions.The performance of the Cu-modified SAPO-34 zeolite is better than that of the unmodified SAPO-34 due to the increased total amount of acid site.