Sustainable Sailing, a start-up established by two brothers with backgrounds in sailing and chemistry, aims to upcycle plastic fibres from sails into new chemicals such as vanillin, the compound used in cosmetics and food products for a vanilla flavour and smell.
Sails are manufactured using hard-wearing synthetic textiles to withstand harsh ocean environments and extreme weather conditions, but they can still need replacing every five years. Professional racing teams go through several sails per event, and there are currently limited options for recycling these technical-grade materials.
Drawing on the engineered biology and green chemistry expertise of collaborators at the University of Edinburgh’s Sadler Lab, the team identified an opportunity to use the waste textiles as a raw material for high-value chemical compounds traditionally derived from petrochemicals.
Sustainable Sailing developed a process to treat sail cloth using high-pressure steam to break the composite material down into its chemical building blocks, which can be used in existing industrial and manufacturing processes.
The business initially focused on turning these building blocks into other types of plastic, but is now looking at the creation of more sustainable materials. The results of the project could see the waste sails being used as an alternative to fossil fuels in the creation of high-value chemicals used in everyday products.
Following prior research that proved the feasibility of turning single-use PET drink bottles into vanillin using engineered E. coli bacteria as a catalyst, the same process is being applied to assess the viability of recycling sailing waste for similar chemicals.
Making polyester-derived chemicals food safe is “absolutely possible” according to Steve Thomas, associate director of applied science and industrial biotechnology at Cambridge Consultants, who was not involved in the work.
“Microplastics would not be the concern for food safety,” he told Professional Engineering. “The output is far more likely to contain microplastics from the polyester shirt that the person opening the bottle was wearing than the process itself.”
Sails are a “curious example” for such a project as there are larger and more urgent sources of plastic pollution, he said, but the generic principle of recycling polyester – commonly used in clothes and drinks bottles – is nonetheless important.
“It's part of an ongoing trend of looking at ways of dealing with our waste streams and using technology and innovation to convert waste streams into something less harmful and something more useful,” Thomas said.
“Removing our dependence on fossil fuels is going to be really important… to make that transition away, we also need to find other sources of input materials to provide all the materials and chemicals that we need for everyday life.”
Scaling up will be the biggest challenge for the work, Thomas added, but he suggested that new AI-based tools could be useful for optimising the process or designing enzymes for more efficient conversion.
Professional Engineering contacted the Sustainable Sailing team for more information about whether the synthetic vanilla will be food safe.
The research collaboration between the company and the Sadler Lab recently received funding through Innovate UK’s bio-based manufacturing Launchpad competition for Scotland, and is also supported by the Industrial Biotechnology Innovation Centre (IBioIC).
Dr Joe Penhaul Smith, founding director of Sustainable Sailing, said: “Water sports and sailing have always been part of our family, so with my scientific background and my brother’s professional sailing experience we hope to use our skills to tackle the marine industry’s environmental footprint.
“Some decommissioned sails are turned into one-off clothing pieces or bags, but there’s no large-scale solution to tackle the waste material. This project aims to find a new circular recycling process where sailcloth can be broken down and repurposed into useful chemical compounds. The added benefit is that these types of compounds are traditionally manufactured from petrochemicals, so marine waste could become an alternative, more sustainable feedstock.
“The next stage of the process is to take it to a much larger scale, as well as working out the supply and demand dynamics to see whether it would be viable to have everyday chemicals manufactured in this way. There is also potential to extract different chemical building blocks for other industrial uses, and we could see additional types of technical textiles being recycled in this way in future.”
Dr Liz Fletcher, director of business engagement at IBioIC, said: “It’s great to see this collaboration between individuals in water sports, chemistry and engineered biology making positive progress, using engineered microbes to deal with waste materials that would otherwise go to landfill. Our work across the bioeconomy continues to prove that one industry’s waste can be a valuable raw material for another. Sustainable Sailing is reducing waste and helping to provide alternatives to petrochemical-derived products, supporting the UK’s ongoing push for net zero.”
Dr Joanna Sadler, chancellor’s fellow in biotechnology and founder of the Sadler lab, University of Edinburgh, said: “We’re delighted to be part of this collaboration which draws upon our expertise to test the viability of using a biological system to upcycle plastic fibres from sails into high-value chemicals. The results from our research have already had major implications for the field of plastic sustainability and demonstrates the power of engineering biology to address real-world challenges.”
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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.