通过分级改性的方法制备了nMetal-K-13X型双金属改性催化剂,并利用XRD、BET、ICP-OES和SEM对催化剂进行表征,考察了催化剂对甲醇甲苯侧链烷基化反应性能的影响。结果表明,反应的甲醇转化率和产物的选择性受扩散因素及催化剂粒径的影响。而在钾改性分子筛催化剂前驱体的基础上,引入第二金属元素的改性方式可有效调控催化剂结构和粒径,可更好地发挥双金属改性催化剂的酸、碱协同催化作用。当K⁺交换5次、Fe₂O₃/KX质量比为0.02时催化活性最优,其侧链烷基化反应的甲醇转化率为99.72%,苯乙烯和乙苯的选择性之和达到92.04%。

nMetal-K-13X type of bimetal modified catalyst is prepared by a sequential modification method,and characterized by X-ray diffraction (XRD),nitrogen adsorption and desorption (BET),elemental analysis (ICP-OES),scanning electron microscopy (SEM) and other characterization methods.Catalytic activity of the catalyst is evaluated on a side chain alkylation reaction using toluene and methanol as substrates.Results show that methanol conversion and product selectivity are affected by diffusion factors and catalyst particle size.Based on potassium modified molecular sieve catalyst precursor,adding Fe,Mg,Zn or other second metal element can effectively control the structure,physical and chemical properties of the catalyst,and enhance the synergy catalytic role of bimetal modified catalyst.The catalyst exhibits the optimal catalytic activity when K+ has been exchanged for 5 times and Fe₂O₃/KX ratio is 0.02,over which the conversion rate of methanol reaches 99.72%,and the combined selectivity of styrene and ethylbenzene reaches 92.04%.

向家兴(1998-),男,硕士研究生,研究方向为分子筛催化剂,994361324@qq.com