Our aim is to fragment wood chips composed of lignin, cellulose and hemicellulose into chemicals with the help of UV light through photolysis in aqueous media. UV light from energy-saving LED lamps allows for breaking bonds of lignin and cellulose selectively to produce high-value chemicals resource- and energy-efficiently instead of thermochemical processes that consume a huge amount of energy and are non-selective. We believe that depending on the wavelength, lignin will be selectively decoupled from cellulose, which can be further used to produce biofuels. The objective is to acquire knowledge about photolysis of the constituents in wood in order to (i) develop a resource- and energy-efficient process to fragment wood chips into its basic constituents and high value chemicals and (ii) to develop a process that is easily implemented at existing pulp and paper mills where the logistics are already available. We will build a photoreactor that provides a UV light source pointing on thin wood chips with a pump that circulates the dissolution media to aid removing formed chemicals. The monochromatic UV LED light source will provide different wavelengths relevant for cellulose and lignin photolysis. The impact of different wavelengths and exposure time will be tested real time (in situ) using magnetic resonance imaging (MRI). Solid materials and the solution will be analysed further after the reaction.
Forskare vid Chalmers, Chemistry and Chemical Engineering, Chemical Technology, Chemical Engineering Design
Funding Chalmers participation during 2018–2019