Sub- and Supercritical Water Liquefaction of Kraft Lignin and Black Liquor Derived Lignin
Research output: Contribution to journal › Review Article › Scientific › peer-review
|Number of pages||42|
|Publication status||Published - 28 Jun 2020|
|Publication type||A2 Review article in a scientific journal|
Black liquor mainly contains cooking chemicals (mainly alkali salts) lignin and the hemicellulose parts of the wood chips used for cellulose digestion. This review explores the eﬀects of diﬀerent process parameters, solvents and catalysts for the HTL of black liquor or black liquor-derived lignin. Using short residence times under near- or supercritical water conditions may improve both the
quality and the quantity of the bio-oil yield. The quality and yield of bio-oil can be further improved by using solvents (e.g., phenol) and catalysts (e.g., alkali salts, zirconia). However, the solubility of alkali salts present in black liquor can lead to clogging problem in the HTL reactor and process tubes when approaching supercritical water conditions.