Ultrapyrolytic cracking of polyethylene - A high yield recycling method

Intrinsic chemical kinetics for the ultrapyrolysis of waste plastics are needed to assess the feasibility for this technology of processing if it is to he used for tertiary recycling. The purpose of this study was to quantify the effect of various operating factors for the pyrolysis of low-density polyethylene (LDPE), a common polymer found in plastic wastes, and determine viable operating conditions for maximizing the production of high value products such as ethylene, propylene, butadiene. Experiments were performed using both a batch micro-reactor and pilot plant sized reactor. The key operating factors considered were temperature and reaction time, with the reaction systems operated under isothermal conditions. In the micro-reactor experiments, LDPE was pyrolyzed at temperatures of 800 degrees C and 900 degrees C, with total reaction times ranging from 350 to 2500 milliseconds. Experiments completed with the pilot plant also produced excellent results with light olefin production reaching 75 wt% at 800 degrees C.