论文部分内容阅读
将硅铝比为38的HZSM-5分子筛与质量分数为30%的粘结剂拟薄水铝石AlO(OH)(焙烧后为γ-Al_2O_3)混合并经Zn改性制得Zn/(HZSM-5+γ-Al_2O_3),通过XRD、FTIR、NH_3-TPD和Py-IR等手段对催化剂进行结构及酸性表征,考察硅铝比和Zn改性对HZSM-5催化剂在液化气芳构化反应中的催化性能。结果表明,HZSM-5添加粘结剂和Zn改性后,强B酸量减少,中等强度L酸量显著增加,B/L比降低。当催化剂m(Zn)/m(HZSM-5+Al_2O_3)为1.57%时,其强、弱酸和B、L酸协同催化作用最优,液化气芳构化收率和目标产物BTEX选择性最好。
The HZSM-5 molecular sieve with a silica-alumina ratio of 38 and the pseudo-boehmite AlO (OH) with a mass fraction of 30% (γ-Al 2 O 3 after calcination) were mixed and Zn / (HZSM -5 + γ-Al_2O_3). The structure and acidity of the catalysts were characterized by XRD, FTIR, NH_3-TPD and Py-IR. The effect of Si / Al ratio and Zn modification on the aromatization reaction of HZSM- In the catalytic performance. The results showed that with the addition of binder and Zn modified HZSM-5, the amount of strong acid B decreased, the amount of moderate acid L increased significantly, and the B / L ratio decreased. When the catalyst m (Zn) / m (HZSM-5 + Al_2O_3) is 1.57%, the synergistic catalysis between strong and weak acids and B and L acids is the best, and the aromatization yield of liquefied gas and the target product BTEX selectivity are the best .