Pyrolysis method of polyolefin waste plastic

Abstract

The invention belongs to the field of resource utilization of waste plastics, and particularly relates to a pyrolysis method of polyolefin waste plastics. The method comprises the following steps: byusing modified activated carbon as a catalyst, putting a reaction amount of modified activated carbon and polyolefin waste plastics into a reactor, quickly conducting heating under the protection of inert atmosphere for catalytic pyrolysis, condensing a product to obtain aromatic hydrocarbon-rich liquid, and collecting non-condensable gas to obtain hydrogen-rich gas. Nitric acid modified activatedcarbon is selected as the catalyst for catalytic pyrolysis of polyolefin waste plastic for the first time, the catalyst is simple in preparation method, low in cost, recyclable and long in catalyticlife, the surface property of the catalyst is improved after nitric acid oxidation treatment, the catalytic activity and target product selectivity of the catalyst are improved, the technological process is simple, reaction conditions are mild, the reaction process can be completed under normal pressure, the reaction period is short, the catalyst cost is low, existing equipment can be used for production, operation is easy, and the method is suitable for large-scale commercial production.

Description

technical field [0001] The invention belongs to the field of resource utilization of waste plastics, and in particular relates to a pyrolysis method of polyolefin waste plastics. Background technique [0002] Polyolefin plastic is an important part of the modern material field, and has been widely used in the world because of its low price and good comprehensive performance. However, while plastic products bring convenience to people's lives, they also generate a large amount of waste. "White pollution" has become a prominent problem in environmental protection. The traditional disposal methods of waste plastics are landfill and incineration, both of which have serious problems. The landfill method not only wastes precious land resources, but also destroys the soil structure, pollutes soil and groundwater resources; although the incineration method avoids encroaching on land resources and can recover part of the heat energy, a large amount of exhaust gas is discharged [0...

AI Technical Summary

Problems solved by technology

However, the hydrocarbon macromolecules generated by plastic pyrolysis are very easy to further polymerize on the active sites on the surface of the molecular sieve, forming coke to cover the active sites of the molecular sieve, blocking the pores of the molecular sieve, and causing the rapid deactivation of the molecular sieve catalyst. The deactivated molecular sieve passes through High temperature roasting regeneration needs to consume more energy

In addition, the economic cost of zeolite catalyst synthesis is high, which is not conducive to large-scale commercial utilization