Boffins to turn carbon emissions into plastic bags

Captured carbon dioxide could soon be used in the production of biodegradable plastic bags, paint stripper, solvents, batteries, anti-knocking agents for petrol and countless other products, according to scientists at Newcastle University, potentially cutting global emissions by 24m tonnes per year.

The team of researchers, led by Professor of organic chemistry Michael North, claims to have developed a catalyst that greatly increases the energy efficiency of converting waste carbon dioxide into chemical compounds known as cyclic carbonates, which are widely used in the manufacture of chemical products, solvents and biodegradable packaging.

"The process of converting CO2 into cyclic carbonates is well established, but it requires very pure CO2, temperatures in excess of 100 degrees and high pressure levels to make it work, all of which means you generate more carbon through the process than you capture at the end," he explained. "We have developed a catalyst that allows the process to take place at room temperature and normal air pressure using carbon captured from a standard source."

According to lab tests, the result is a huge net reduction in carbon emissions that would potentially allow chemical firms to lock CO2 into useful products.

"The projected demand for cyclic carbonates is 48m tonnes per year and 50 per cent of them are made up from CO2 so there is the potential to capture about 24m tonnes of CO2 a year for re-use in this way," said North.

He added that in the event that the resulting cyclic carbonates are used to make biodegradable plastics, the CO2 conversion process could form part of a " closed loop" system, albeit one with considerable leakage.

"If you use the cyclic carbonates to make biodegradable bags the CO2 will leak back into the atmosphere as they break down," he explained. "But if, as is increasingly the case, they were to go into an incinerator to generate energy you could recapture much of the CO2 emissions and start the whole process again. "

The calcium carbonates could also be used in the production of dimethyl carbonate, which can be used as an anti-knocking agent for improving the fuel efficiency of petrol. "Using the end product to help burn petrol might not sound green," admitted North. "But in oxygenating the fuel it can significantly improve fuel efficiency."

The Newcastle University team now plan begin work on a pilot project for the technology and North expressed hope that a commercial-scale demonstration plant could be up and running within five years.

The breakthrough is the latest in a series of projects designed to turn captured CO2 into a commercially viable product. Earlier this year, UK startup Carbon 8 Systems outlined plans for using captured CO2 to make building aggregate, while industrial giant Bayer is currently working on a project to turn carbon emissions into polycarbonate plastics used in the production of CDs, DVDs, lenses and bottles.