A non-toxic and magnetically recoverable catalyst that could revolutionise the plastics recycling industry

In today’s post we have had the pleasure of meeting Dr. Imanol de Pedro del Valle (ORCID Code, 0000-0002-6694-9759), current professor-researcher at the University of Cantabria, together with his colleagues Dr. Israel Cano (0000-0003-3727-9327) and Dr. Carmen Martín (0000-0001-8687-6887), who currently hold assistant doctoral positions at the University of Cantabria. Carmen Martín (0000-0001-8687-6887), who currently hold assistant doctoral positions in the Department of Inorganic Chemistry at the Complutense University of Madrid, to talk about the development of a new catalyst for the decomposition of plastics; specifically of the polymer PET (polyethylene terephthalate) in the starting monomers, BHET (bis(2-hydroxyethyl) terephthalate).

This catalyst, with high industrial potential, could help to boost the circular economy in the environmental sector. The result of this multidisciplinary work, led by these three researchers, has been published in Applied Catalysis B: Environmental (I.P 19.5; ranking 1/50 in the catalysis discipline, with more than 40 citations in one year) and the journal C&EN (Chemistry news from around the world) of the American Chemical Society (ACS), the most reliable source of news and information on the latest developments and technologies for scientists around the world, has highlighted it as one of the 10 most popular articles-patents worldwide in 2020 on plastics recycling.  

Interview

What was the beginning of this project and how did you identify the need for a more efficient process for recycling plastics?

In Europe alone, around 65 million tonnes of plastics are produced every year and it is estimated that this figure will continue to rise in the coming decades. Of the two current forms of plastic recycling, mechanical and chemical, the latter is the least used industrially due to its higher economic cost, although it is the most promising, as it is possible to obtain the basic monomers from which to re-make plastics of the same quality as the originals. This project was born with the idea of improving the industrial chemical process in the plastics recycling sector by developing an innovative technique and technology in this new industrial recycling sector.

It all started in 2019, when a proposal was made for funding of this three-year project in the State call for R&D&I oriented to the Challenges of Society in the framework of the State Programme for the Generation of Knowledge and Scientific and Technological Strengthening of the R&D&I System. The project was considered very promising scientifically but not financially fundable.  The University of Cantabria, by means of what is known as a “bridge project”, granted a financial subsidy of 20% of the total amount requested. Thanks to this, the catalyst was conceived and developed. The second stage was to test it. To do this, Imanol de Pedro says that he was able to spend two months at the University of Nottingham (England), at the Carbon Neutral Laboratory, thanks to the PDI support programme and the support of the Magnetism of Matter research group of the UC’s Department of Earth Sciences and Condensed Matter Physics, where he is currently working. There he met Dr. Israel Cano and Dr. Carmen Martin.  (colleagues, friends and partners for a possible industrial development) who led and completed the testing trials.

How does the magnetic catalyst work to break down plastics?

Chemical recycling or depolymerisation of plastic mainly involves the conversion, breaking down or reduction of the main polymer chain into smaller units such as monomers and oligomers (larger chain fragments). To split or fragment PET, the addition of some reagents or solvents is used. For example, if water is used, this is hydrolysis; if acids are used, this is acidolysis; and if glycols are used, this is glycolysis. It is in this last reaction that this catalyst has been tested, where its greatest innovation is its easy recovery and reuse, based on the application of magnetic fields. The simplicity of this process considerably improves the recovery of current catalysts, vacuum distillation or centrifugation; complex and expensive industrial processes for the industry.

Can it be used with all types of plastics, and with which plastics has the system performed best?

The answer to this question remains to be proven. So far it has only been applied to the glycolysis of PET (the plastic mainly used in bottles and food packaging and the most widely used in the world). What is clear is the potential of this new catalyst, but no conclusions can be drawn without tests on other plastics such as PVC (polyvinyl chloride) or PP (polypropylene) among others.

What are the future developments that this type of technology could have, and what are your research plans for the future?

From an applied point of view, the next objective would be to demonstrate that the technology is viable in pre-industrial processes. We are currently looking for a financial investment to bring this technology to a pilot plant.

From a basic research point of view, improving the catalyst, other types of chemical compositions of the material, can improve its energy efficiency and recyclability.

How soon could this technology be integrated into plastic recycling companies?

One of the keys is investment. That is, the amount of resources and people. With adequate funding it can take less than 2 years. The results of a pilot plant could be ready in less than a year as the catalyst and the process are optimised and tested in the laboratory.

What economic impact can the implementation of this technology have on a plastic recycling company?

Today, recycling post-consumer plastic to benefit the environment is an obligation, but it is also an industrial opportunity. There is a mismatch between supply and demand for this post-consumer material, because once it has been recycled and obtained, using it in the production of a new plastic reduces energy consumption and C02 emissions for the production of a new plastic. In addition, we reduce the amount of solid waste going to landfill. On an industrial level, several chemical plastics recycling plants have been set up in the past year. This is a great opportunity to create new companies and jobs in a post-pandemic context that makes it more essential than ever.

The circular economy is increasingly present in today’s society. Does this have a positive impact on the field of research?

Developing innovative techniques and technologies that break down plastic polymers into starting monomers, guarantee the safety and health of citizens, protect the environment and improve the competitiveness of industry is a priority of the European Framework Programme for Research and Technological Development. Specifically, within the European Circular Economy Strategy where by 2030 all plastic packaging distributed in the EU will be 100% recyclable.  I believe that we are on time to improve the health of our planet and we can also benefit economically. The plastics recycling sector in Europe is changing, European legislation has more stringent requirements and there is social pressure from consumers to improve the responsible management of these compounds.

How can digitalisation help to improve the use of waste and recyclable materials?

Digitalisation is essential in a globalised world. We must ensure that each waste product is an economic medium and that it is passed on to us in terms of money, and digitalisation will facilitate this process by making it easier to generate business contacts. In addition, this can be transferred not only to the business environment, but also to the street level. Through digitisation, new areas can be covered and a lot of knowledge can be shared, thus achieving a wide dissemination.

Leading publications in the sector have highlighted the catalyst as one of the most innovative and efficient products in plastics recycling. How has the team received this recognition?  

Congratulations are always appreciated, that is undeniable.  But the most important thing for us is to do our bit to stop the spread of plastics. If we don’t do this, the Earth will become extinct in a few years. It will then recover as in the last 5 great extinctions. Even if it takes 10 million years to recover, that is a pittance compared to the 4.543 billion years it is 4.543 billion years old. Currently only less than 30% of the plastics that are recycled are reused. Burning them or sending them to landfill does not make them go away; plastic takes thousands of years to degrade. It is no longer about us…we are accumulating more and more microplastics in our bodies, but…What kind of world do we want to leave our children? A world full of plastics, or a world full of trees?

ScrapAd is delighted to have been able to talk about this new catalyst, that will start to reverse the effect of the seas of plastic we are creating, and to bring you information about the recycling of the future. Discover our platform for buying and selling scrap metal and other recyclable materials, and also our blog where we talk about the plastic recycle code.