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Lignin‐First Monomers to Catechol: Rational Cleavage of C−O and C−C Bonds over Zeolites
Author(s) -
Wu Xian,
Liao Yuhe,
Bomon Jeroen,
Tian Guilong,
Bai ShaoTao,
Van Aelst Korneel,
Zhang Qiang,
Vermandel Walter,
Wambacq Ben,
Maes Bert U. W.,
Yu Jihong,
Sels Bert F.
Publication year - 2022
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.202102248
Subject(s) - lignin , chemistry , catechol , alkylation , softwood , organic chemistry , zeolite , monomer , catalysis , hydrodeoxygenation , biorefinery , vanillin , lignocellulosic biomass , selectivity , raw material , materials science , polymer , composite material
A catalytic route is developed to synthesize bio‐renewable catechol from softwood‐derived lignin‐first monomers. This process concept consists of two steps: 1) O ‐demethylation of 4‐ n ‐propylguaiacol (4‐PG) over acidic beta zeolites in hot pressurized liquid water delivering 4‐ n ‐propylcatechol (4‐PC); 2) gas‐phase C ‐dealkylation of 4‐PC providing catechol and propylene over acidic ZSM‐5 zeolites in the presence of water. With large pore sized beta‐19 zeolite as catalyst, 4‐PC is formed with more than 93 % selectivity at nearly full conversion of 4‐PG. The acid‐catalyzed C ‐dealkylation over ZSM‐5 zeolite with medium pore size gives a catechol yield of 75 %. Overall, around 70 % catechol yield is obtained from pure 4‐PG, or 56 % when starting from crude 4‐PG monomers obtained from softwood by lignin‐first RCF biorefinery. The selective cleavage of functional groups from biobased platform molecules through a green and sustainable process highlights the potential to shift feedstock from fossil oil to biomass, providing drop ins for the chemicals industry.