Production of aromatic monomers from catalytic pyrolysis of black-liquor lignin

Lignin, mostly existing in forms of solid residue from pulping process of biomass, has been intensively investigated as a potential feedstock for producing high-value chemicals. In this work, lignin precipitated from the acidified black liquor was pyrolyzed under different temperatures (550, 650, 800 and 900 degrees C) using the analytical pyrolysis technology coupled with GC/MS (Py-GC/MS). The experiments in absence and presence of five solid zeolite catalysts (HZSM-5(25), HZSM-5(50), HZSM-5(210), H-beta and H-USY) were carried out, in order to identify the optimal reaction temperature and the best catalyst for producing aromatic monomers (such as guaiacol, phenol, benzene, toluene, etc) from lignin. HZSM-5(25) played an important role in promoting the yield of aromatic monomers from lignin under 650 degrees C, while H-USY enhanced the formation of aromatic hydrocarbons such as benzene, toluene and xylene. (C) 2015 Elsevier B.V. All rights reserved.