Potential use of biomass for separation of lignin by hydrotropic extraction

Research output: Contribution to conferenceAbstract


The demand for energy in the world is increasing steadily. As the standard of living for people in the developing countries is increasing so is the net energy use per capita. The main contributor to the energy consumption is the use of fossil fuels, which is also the major emission source for carbon dioxide. Carbon dioxide is in turn one of the most significant greenhouse gases and will enhance temperature rise on earth which in turn will lead to climate change.

As fuels derived from fossil sources is a major contributor to these emissions, the need to find alternatives is urgent. Fuels derived from biomass could be a future potential replacement since the biomass itself will be carbon neutral. One potential way of using biomass is to produce sugars that can later be fermented into ethanol. This has been in focus of research for the last couple of decades. However, the process of fermentation into ethanol can only utilize sugars extracted from the biomass which leaves some parts of the biomass unused. One such component is lignin.

Lignin is a biopolymer consisting of three different monomers: coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol. All of the monomers are aromatic alcohols and the polymer itself therefore have a structural resemblance to the polyaromatics present in oil. Lignin could consequently be a potential source for future production of green fuels such as gasoline, diesel and jet fuel. However, one problem frequently encountered with lignin extraction processes today is that the structure of the polymer is often both altered and will, after the process, contain impurities, for example sulfur, depending on which method that was used. This could be a potential problem in the following conversion steps.

One technology that could be used in order to retrieve a lignin with a less altered structure is hydrotropic extraction. The hydrotrope is an amphiphilic molecule with both a hydrophobic and a hydrophilic part. As the concentration of the hydrotrope in a water solution reaches a critical value it will increase the solubility of components otherwise insoluble in water, such as lignin. After the hydrotropic cooking, the lignin can be recovered by simply adding water. As the concentration of the hydrotrope decreases the lignin will precipitate in the water solution and can then be filtered off. By utilizing hydrotropic extraction for the recovery of lignin the whole biomass, not only the hemicellulose and cellulose, could be used for production of green fuels. In this project I will investigate the possibility of using a hydrotropic solution for the extraction of lignin from hardwood. Preliminary results will be presented.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Chemical Engineering
Original languageEnglish
Publication statusPublished - 2016
Publication categoryResearch
EventEuropean Symposium on Biochemical Engineering Sciences - Dublin, Ireland
Duration: 2016 Sep 112016 Sep 14


ConferenceEuropean Symposium on Biochemical Engineering Sciences
Abbreviated titleESBES