Lignin as a Sustainable Raw Material: Enzymatic Decomposition of Lignin to Obtain Aromatic Synthesis Components

摘要

Due to the growth in population and increasing demand, securing the supply of food, raw materials and energy is one of the greatest challenges to the chemical industry in the 21st Century. Up to now, fossil raw materials have been the only significant source of raw materials for many products such as plastics, resins, adhesives and many platform chemicals. In the long term, integrated processing of "non-food" biomass will play an important role in the production of energy, biogas, fuels and chemicals [1]. With a proportion of dry matter of 20 - 30% for woody plants, lignin is one of the main components of the available ligno-cellulose biomass. This extremely complex bio-polymer, consisting of phenyl-propane units, is used by plants as a supporting material and as protection against pests (Fig. 1). Every year, approximately 50 million tons of lignin are produced as a by-product of the cellulose industry. Of this, 98 % is used for energy, without utilization of the material potential of the bio-polymer [2]. At present, only a small proportion of the lignin is utilized in biomaterials, paints or in the food industry. Up to now, the chemical or enzymatic decomposition of lignin for the extraction of aromatics has not been possible on a technical scale. A reason for this is the lack of suitable catalysts [3].