TY - JOUR
T1 - Decomposition of lignin model compounds by Lewis acid catalysts in water and ethanol
AU - Guvenatam, B.
AU - Heeres, E.H.J.
AU - Pidko, E.A.
AU - Hensen, E.J.M.
PY - 2015
Y1 - 2015
N2 - The conversion of benzyl phenyl ether, diphenyl ether, diphenyl methane and biphenyl as representative model compounds for a–O4, 5–O4, a 1 (methylene bridges) and 5–5' lignin linkages was investigated. We compared the use of metal chlorides and acetates. The reactions were studied in sub- and supercritical water and supercritical ethanol between 300-400 °C. At low temperature in water, Lewis acids mainly catalyzed condensation of hydrolysis products of the dimeric model compounds. At higher temperature, mono-aromatic products were formed. The yield of monomeric products was higher in ethanol than in water. The preference for ethanol is due to extensive alkylation of the mono-aromatic products, which inhibits their condensation into larger products. The highest yields of deoxygenated mono-aromatics were obtained using Lewis acid catalysts at 400 °C in supercritical ethanol. The preferred Lewis acid catalysts were Fe, Cu, Ni and Al chlorides.
AB - The conversion of benzyl phenyl ether, diphenyl ether, diphenyl methane and biphenyl as representative model compounds for a–O4, 5–O4, a 1 (methylene bridges) and 5–5' lignin linkages was investigated. We compared the use of metal chlorides and acetates. The reactions were studied in sub- and supercritical water and supercritical ethanol between 300-400 °C. At low temperature in water, Lewis acids mainly catalyzed condensation of hydrolysis products of the dimeric model compounds. At higher temperature, mono-aromatic products were formed. The yield of monomeric products was higher in ethanol than in water. The preference for ethanol is due to extensive alkylation of the mono-aromatic products, which inhibits their condensation into larger products. The highest yields of deoxygenated mono-aromatics were obtained using Lewis acid catalysts at 400 °C in supercritical ethanol. The preferred Lewis acid catalysts were Fe, Cu, Ni and Al chlorides.
U2 - 10.1016/j.molcata.2015.09.007
DO - 10.1016/j.molcata.2015.09.007
M3 - Article
SN - 1381-1169
VL - 410
SP - 89
EP - 99
JO - Journal of Molecular Catalysis A: Chemical
JF - Journal of Molecular Catalysis A: Chemical
ER -