Plastic waste on beach

Plastic debris and seaweed cocktail make oil

Image courtesy of shutterstock_179459936 plastics spread on beach


PML researcher, Dr Mike Allen has been awarded a Catalyst grant from the Roddenberry Foundation to help accelerate his idea for converting plastic debris into biofuel.

Mike’s idea was inspired by a walk along the beach with his children. Normally the family would pick up plastic litter, take it home and dispose of it responsibly. They also collect seaweed for Mike’s research which is investigating how algae can be converted into biofuel. Plastic can also be turned back into oil so Mike wondered if by collecting algae and the plastics that, sadly, are so often tangled with it he could bring the two together turning the mess of seaweed and plastic debris into biofuel in one process. The $15,000 award will enable him to take the first step, investigating the possibilities and developing techniques at a laboratory scale. “I can see the time when we can scoop up harmful algal blooms (HABs), that occur off our coasts and threaten our health and that of coastal species, and the plastic litter that we know floats with them to convert it into useful products such as oil and fertilizers.  We have already managed to produce oil from algae in the laboratory and we know we can do the same with plastics, explained Mike.” Now with fellow researcher Dr Chris Chuck at the University of Bath, they are looking to develop a process that can be run either continuously or opportunistically (when required) in areas where plastics and HABs or seaweeds occur, accumulate or associate. “It will convert a problem into a solution, generating economic returns on a remediation activity for biomasses that are almost always unwanted and sometimes dangerous. The process being developed is known as hydrothermal liquefaction, which converts organic (carbon containing) material into 4 phases: a bio oil, an aqueous phase rich with phosphate and nitrate, an inert char containing stable metals, and a gas (mostly CO2). It does this using water as a solvent and through the application of high pressures and temperatures. We call this ‘geology- in-a-tin’ as it mimics the natural events of millions of years ago that originally converted dead organisms into the oil we extract from wells today”, added Mike. Mike has high hopes of success and pointing out that it could solve a number of challenges at the same time: “Plastic will no longer pollute our oceans and we will have a way to alleviate the impacts of harmful algal blooms. It will be economical to 'harvest' these biomasses, and convert them into fuel and fertiliser, thereby helping to alleviate the energy and food crisis humanity will be facing in the future. The versatile process can be applied at specific beach locations, open ocean gyres accumulating debris and at sites of harmful algae blooms.”

“The Catalyst grants are designed to spur innovation and to support untested ideas that have great potential for impact, which is why we’re investing in Mike and his lab’s work  ” says Lior Ipp , CEO at Roddenberry Foundation.

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