纳米HZSM-5沸石催化剂上催化裂化轻汽油的芳构化

Aromatization of Fluid Catalytic Cracking Light Gasoline over Nano-HZSM-5 Zeolite Catalyst

利用小型固定床加压反应器在纳米 HZSM-5沸石催化剂上进行了流化催化裂化(FCC)轻汽油(馏出温度小于等于85℃的馏分)的芳构化反应。实验结果表明,在反应温度为360～400℃、反应压力为1.0～3.0 MPa、重时空速为1.0～4.0 h^(-1)、V(H_2)∶V(原料)为260、反应时间48 h 的条件下,FCC 轻汽油中的 C_5^+烯烃转化率为39.11%～97.92%,产物中芳烃净增量为2.59%～19.05%,说明 FCC 轻汽油可在纳米 HZSM-5沸石催化剂上有效进行芳构化反应。汽油收率低和催化剂失活快是 FCC轻汽油在纳米 HZSM-5沸石催化剂上进行芳构化反应需要解决的两个主要问题。对纳米 HZSM-5沸石催化剂进行必要的改性处理及脱除原料中的二烯烃杂质呵以改进 FCC 轻汽油芳构化催化剂的性能。

Aromatization of fluid catalytic cracking （FCC）light gasoline （distillate temperature of fraction is equal to or below 85 ℃ ） over nano-HZSM-5 zeolite catalyst was studied in a small pressured fixed-bed reactor. Aromatization can be promoted effectively by nano-HZSM-5 zeolite catalyst. Under the conditions of reaction temperature 360 -400 ℃, reaction pressure 1.0 -3.0 MPa, WHSV of feedstock 1.0 - 4.0 h^- 1, V（ H： ） ： V（feed） 260 and reaction time 48 h, conversion of C5^＋ olefins in FCC light gasoline reaches 39.11% - 97.92%, while the actual increment of the aromatics content in liquid product is about 2.59% - 19.05%. Low yield of the product liquid oil and the fast deactivation of catalyst are very tough problems concerning the aromatization of FCC light gasoline over unmodified HZSM-5 zeolite catalyst. It is concluded that both modification of nano-HZSM-5 zeolite and removal of dienes from FCC light gasoline feedstock are absolutely required in order to improve the performance of the catalyst in aromatization.