Novel catalytic plastic waste-to-energy technology for New Zealand

Plastics are used in many applications and are closely integrated into our daily life, for example, shopping bags, plastic beverage bottles, containers, and packaging of consumer-based products and many more uses. Currently, a total of 735,000 tonnes of packaging plastics are consumed in New Zealand every year, with only 10-12% being recyclable and the remainder were mostly disposed of to landfills each year. About 15,000 tonnes of New Zealand’s recyclable plastics had been sent to other countries (mainly to China) annually. However, very recently, the Chinese government forbade the importation of 24 types of solid waste, including New Zealand’s exported plastics, resulted in piles of plastics accumulating within the country at an increasing rate. The interim, inevitable solution for New Zealand is to divert most of these plastic wastes to landfills, that is expected to incur increases in the waste levies for New Zealanders. More importantly, the toxic landfill leachate can cause severe soil, water, and hence, food contamination. It is clear that such an interim solution is not sustainable for the country in the longer term. This research aims to respond to the most recent plastic waste crisis and to provide a technological solution to the problem.

The Ph.D. project will merge our knowledge in pyrolysis (decomposition brought about by high temperatures) and industrial catalyst design (making a stable and durable catalyst) to develop a robust degradation method that can deal with a wide range of plastic waste materials from polyethylene terephthalate (PET), to polyvinyl chloride (PVC), and to polycarbonate (PC), etc. While plastic degradation by pyrolysis has been studied in the past two decades, the major technological challenge lies under the low physical and chemical stability of the catalysts under the conditions required by pyrolysis. This project will develop a binder-free hierarchical/mesoporous zeolite catalyst with ultra-high resistance to catalyst deactivation (and coke formation) and with high thermal stability for industrial use. The new catalyst will be highly durable for long term use in catalytic pyrolysis of plastic wastes. The catalytic pyrolysis technology will be able to produce liquid fuels (diesel, gasoline, and other products) with high selectivity that are suitable for engines. The composition of the fuel will be adjustable to fit for different commercial purposes, such as fishing vessels, cruise-ferries, heavy construction equipment, etc.

Key qualifications and skills

First-class honours. Prior knowledge and experience in catalysis.

Does the project come with funding

No - student must be self-funded. 

Final date for receiving applications

Ongoing

Keywords

Plastics; catalysis; zeolites