Israel Ben · Researchers at Gurion University are studying the biodegradation of bacteria. — An easier and more environmentally friendly way to break down and recycle PET (polyethylene terephthalate). PET is the most common type of plastic found in food and beverage packaging and textile products.

According to the introduction, as early as November last year, this · BGN T Technology, a company owned by Gurion University, partnered with Portugal's Ecoibé ria signed a research collaboration agreement to study and demonstrate the effectiveness of PET bacterial biodegradation. The

project's findings may simplify the current cumbersome plastic recycling process, in which plastic bottles are collected from recycling bins, then separated by type and color, then ground into small pieces and melted into sheets of raw materials and fibers.

20 years of research

this & bull; Professor Ariel Kushmaro, from the Department of Biotechnology Engineering at Gurion University, said: ""Our research involves the decomposition of various plastic polymers.

The principal investigator of the project is Professor Alex Sivan, who started working in this field 20 years ago, when the world's research on the biobreakdown of plastics was still in its infancy.

Professor Kushmaro said: ""We started from the microbial demand for energy and carbon sources, and realized that biodegradation is derived from the microbial demand for energy and carbon sources."" .

To do this, they break down organic matter. — Carbon chains, like sugars and even proteins. We thought that because plastics, polyethylene and PET are also made up of carbon chains, we should prepare one. Enriched cultures. — — Soil contaminated with plastic or PET over the years contains primitive groups of bacteria.

The obvious hurdle is that polyethylene is considered non-biodegradable due to its highly stable carbon-carbon bonds. Therefore, its bacterial breakdown must be artificially facilitated in the laboratory.

""In addition to the bacteria, we add substances that we want them to break down and let them work for a few weeks. After several attempts, we found a microbe that used polyethylene as carbon and energy during its growth. ""These bacteria can process these polymers,"" Cushmaro explains.

""We know that in order for bacteria to biodegrade the carbon bonds in plastic polymers, they have to be grown in a carbon-free environment, so the bacteria have no choice but to consume the only carbon available in the plastic to survive,"" Cushmaro said. .

""Of course, it's not enough just to supply the bacteria with carbon chains. We have to give them various additives, such as sources of nitrogen and phosphorus, to make it easier for them to break down.""

Kushmaro, Sivan and their team eventually found several types of bacteria that were able to successfully degrade polyethylene microplastics in soil samples.

""We found that within 30 days, the weight of the soil was reduced by 10 to 20 percent just through the decomposition activity of the bacteria, which released carbon dioxide during respiration,"" Kushmaro revealed. .

Ecoibé ria is a company that specializes in recycling PET bottles. The company recognized the potential of Kushmaro and Sivan's research and approached BGN technology. The collaboration will include laboratory tests in Israel to study how bacteria break down PET and whether intermediate byproducts can be separated and used as feedstock in the plastics industry.

If so, there will be a new round of investment pilots. If the trial turns out to be successful, then the technology will need at least two to three years of additional research before it can be applied in industrial Settings.

More efficient, higher quality

""Today, if you want to recycle effectively, you have to separate water bottles from baby bottles, shampoo containers, etc."" ""the need to separate all types of plastic from each other is what makes the process so complicated,"" said Dr. Noam van der Hal, who studies microplastics at the University of Haifa in Israel. .

""In fact, it is very difficult to recycle plastic items back to their original level of quality and performance. Now, instead of recycling a bottle into a bottle, we recycle it into a playground floor, bench, or building material. So it's not recycling in the full sense.""

Kushmaro believes that the product obtained by biological decomposition is the original raw material. We work with Ecoibé ria to take this project forward, to break down PET pieces into raw materials, so that the product can be sold as raw materials. The idea is that microbes or enzymes will break down molecular polymer chains in order to extract clean raw materials from the mixture and replicate PET in the same way that traditional industrial practices do. Kushmaro said.

So, is this new process economically viable? Kushmaro argues that biodegradation is much cheaper than thermal or chemical recycling, giving it a competitive advantage in the raw material market. ""They are looking for holistic solutions that can improve recycling. This is also related to the environmental trend in the European market, which encourages investment in ""green"" projects that reduce environmental pollution. Our study is part of this welcome trend."" Kushmaro said.