固体超强酸SO42-/TiO2-SiO2催化废旧塑料裂解制燃油

Fuel—Oil Production from Catalytic Pyrolysis of Waste Plasticover the Solid Super Acid SO42-/TiO2—SiO2

关键词:  废旧塑料  固体超强酸  催化裂解  燃油

Key words:  waste plastics  solid super acid  catalytic pyrolysis  fuel oil

摘要:

本文采用溶胶-凝胶法和浸渍法制备了SO42-/TiO2-SiO2固体超强酸催化剂,并应用于聚丙烯废塑料催化裂化制燃油。同时考察了催化剂组成、焙烧温度、反应温度、催化剂用量对塑料催化裂解反应的影响。结果 表明,在硫酸/TiO2-SiO2质量比为3、TiO2/SiO2摩尔比为1、经500℃焙烧所制备的固体超强酸SO42-/TiO2-SiO2催化剂对塑料裂解反应具有最好的催化性能;在最佳裂解工艺条件(反应温度420℃、催化剂用量2 g/10 g塑料)下,液体燃油的收率可达78.6%。催化剂的正丁胺-TPD表征结果表明,SO42-/TiO2-SiO2催化剂表面具有较多的强酸和超强酸位,XRD结果表明,金红石相TiO2对超强酸位的形成有利。

Abstract:

SO24-/TiO2—SiO2 solid super acid catalysts wereprepared by sol—gel and impregnation methods, and applied in thecatalytic pyrolysis of waste plastics containing polypropylene in thepresent work. At the same time, the effects of the catalyst composition, calcination temperature, pyrolysis temperature and catalyst amount on the pyrolysis of waste plastics were also investigated in details. The results showed that the optimum conditions for the preparation of solid super acid SO24-/TiO2—SiO2 were H2SO4/TiO2—SiO2 mass ratio of 3, TiO2/SiO2 molar ratio of 1, and calcinationtemperature 500°C. Under the optimum pyrolysis conditions (tem-perature 420℃,catalyst amount 2g/10 g waste plastics), SO24-/TiO2—SiO2 gave a yield of liquid fuel up to 78. 6%.The n—butylamine—TPD characterization showed that the polypropylene catalytic pyrolysis mainly occurred over the super add sites of SO24-/TiO2—SiO2 catalysts. XRD results showed that rutile TiO2 was beneficial for the formation of super acid sites.