A PROCESS being developed by researchers in the UK and India to convert medical waste – such as PPE used during the Covid-19 pandemic – into hydrogen fuel has received £47,000 (US$63,000) from the Welsh Government.
The technique will use a photoreactor to simultaneously destroy pathogens as well as break down waste. The research is being led by Swansea University, which had previously developed a photoreactor that can convert waste plastic to hydrogen fuel. The same photoreactor will be used in the new project, although new photocatalysts will be developed. The collaboration also includes epidemiologists at India’s King Institute of Preventive Medicine & Research and Thiruvalluvar University, and the nanomaterials group at the Indian Institute of Technology Mandi.
The Covid-19 pandemic and the resulting need for extra PPE is creating additional medical waste. Medical waste is currently disposed of via incineration, which generates greenhouse gases. Photoreforming doesn’t generate emissions and it works at an ambient temperature.
Moritz Kuehnel, project lead and Senior Lecturer in Chemistry at Swansea, said: “Since the outbreak of the Covid-19 pandemic, we have witnessed a global surge in single-use medical waste and PPE polluting the environment – such as disposable face masks littering beaches. The NHS already spends more than £700m every year on waste disposal, even before Covid waste. Applying our technology to reprocess just 1% of this waste would save millions and mitigate pollution at the same time.”
The process can use a range of feedstocks and different mixtures of waste. While PPE is a key target as a feedstock as it is unrecyclable and currently used in great quantities, other medical waste such as syringes could be used. The process is also not limited to medical waste and the researchers hope that the technology will be used for a broad range of wastes.
Sudhaghar Pitchaimuthu, Co-investigator and Sêr Cymru-II Rising Star Fellow at Swansea’sCollege of Engineering, said: “The simplicity and low cost of photoreforming make it easier to implement in countries that do not have an established recycling system. By turning this hazardous waste into a resource, we aim to provide a commercial incentive to collect waste from the environment and prevent littering in the first place.”
Along with hydrogen, the photoreforming process could also produce other products. “One of the objectives of our current study is to identify the key waste decomposition products with different types of waste and various catalysts,” said Kuehnel. “This information will enable us to optimise the process for generating valuable chemical feedstocks with a high selectivity. In previous studies, we have seen the formation of organic acids such as formic and acetic acid from waste, which are important industrial products.”
The process itself is inexpensive to scale up, but there are challenges involved with the development of a larger photoreactor regarding light penetration. The researchers expect it to be at a commercial scale within five years and are currently looking for industry partners to commercialise the technology.
Catch up on the latest news, views and jobs from The Chemical Engineer. Below are the four latest issues. View a wider selection of the archive from within the Magazine section of this site.