Lignin: An Alternative Source for the Production of Chemicals?
Sustainable process-product development & green chemistry
Green Organic Synthesis Routes (T1-2)
Keywords: lignin, alkaline, oxidation, stability, vanillin
Biomass represents a renewable and alternative source for the production of chemicals. A variety of conversion or gasification processes have been proposed to use biomass as an alternative energy resource to minimize the consumption of fossil fuels.[1] Wood is mainly composed of cellulose, hemicelluloses, lignin and extractives. Lignin is the second most abundant biomass component after cellulose and accounts for 18-40 wt% of the dry wood depending on the wood specie. The use of lignin as a chemical is limited due to low-added-value applications, which include its use as a binder, dispersant, emulsifier and metal sequestrant. However, lignin is composed of units which are a rich source of phenolic compounds that can be used as useful buildings by the chemical manufacturers, upon thermal degradation.[2]
Hundreds of attempts to produce chemical building blocks from lignin have been unsuccessful in obtaining yields and selectivities high enough for a process to be economically viable. In a careful evaluation of the state of the art, we have investigated the shortcomings of current methods to produce chemicals from lignin. By means of benchmark procedures and product stability tests we were able to show that simple methods are not suitable for the production of chemicals from lignin. Based on this experience, we propose and show a new method for the conversion of lignin to high-value products, which is capable of overcoming many well-known difficulties.
[1] Okuda, K et al., Fuel Processing Technology, 85, 2004, 803-813.
[2] Amen-Chen, C et al., Bioresource Technology, 79, 2001, 277-299.
Presented Tuesday 18, 16:40 to 17:00, in session Green Organic Synthesis Routes (T1-2).
