《29_ftp》.pdf

Lignin 29 Madhav Prasad Pandey1,2 Review Chang Soo Kim1 1 Lignin Depolymerization and Conversion: Clean Energy Center, Energy Division, Korea Institute A Review of Thermochemical Methods of Science and Technology (KIST), Seoul, Republic of Korea. The structure of lignin suggests that it can be a valuable source of chemicals, par- 2 ticularly phenolics. However, lignin depolymerization with selective bond clea- University of Science and vage is the major challenge for converting it into value-added chemicals. Pyrolysis Technology, Daejeon, Republic of Korea. (thermolysis), gasification, hydrogenolysis, chemical oxidation, and hydrolysis under supercritical conditions are the major thermochemical methods studied with regard to lignin depolymerization. Pyrolytic oil and syngases are the primary products obtained from pyrolysis and gasification. A significant amount of char is also produced during pyrolysis. Thermal treatment in a hydrogen environment seems very promising for converting lignin to liquid fuel and chemicals like phe- nols, while oxidation can produce phenolic aldehydes. Reaction severity, solvents, and catalysts are the factors of prime importance that control yield and composi- tion of the product.