Solvent assisted catalytic conversion of beech wood and organosolv lignin over NiMo/γ-Al₂O₃

Abstract

Lignin in biomass is degraded to a handful of chemicals in the presence of a NiMo/Al2O3 catalyst and ethanol medium.

Recent Advances in the Catalytic Depolymerization of Lignin towards Phenolic Chemicals: A Review

“…The catalytic conversion of organosolv beech lignin over sulfided NiMo/γ‐Al 2 O 3 could only afford 4.3 wt % yield of monomers, while direct conversion of beech wood could provide 18.1 wt % yield of monomers under the identical conditions . The yield difference between the direct conversion of biomass and a two‐step process involving organosolv isolation and subsequent depolymerization was also observed by Zhai et al.…”

Development of ‘Lignin-First’ Approaches for the Valorization of Lignocellulosic Biomass

“…Later, interesting works to provide highly useful molecules in a one-pot, one-step process were the direct production of light naphtha (n-hexane, n-pentane, cyclohexane, and methylcyclopentane) by the Sels group in 2015 [ 42 ], which was developed further in 2018 [ 65 ] and 2020 [ 83 ] producing phenol and propylene. Liquid alkylcyclohexanes and polyols over Ru/C catalysts [ 70 ], and propylphenols, C 5 –C 6 ketones, and furans over sulfided NiMo/Al 2 O 3 catalysts [ 94 ] were formed in other one-pot one-step processes.…”

“…The total utilization of lignin and carbohydrates in eucalyptus towards phenolics, levulinic acid, and furfural was emphasized in another paper in 2020: Pd/C catalyst in methanol solvent was used in the hydrogenolysis step, 50 wt % maximum phenolic monomers yield was achieved (entry 74 in Table 1 ) [ 93 ]. Beech wood was directly converted into lignin derived monomers (20 wt % yield) and dimers and holocellulose derived light hydrocarbons in the presence of a sulfided NiMo/Al 2 O 3 catalyst in ethanol solvent at 260 °C (entry 75 in Table 1 ) [ 94 ].…”

Platform chemicals from hardwood black liquor via hydrothermal liquefaction: influence of process conditions on product yields and quality

“…11 Similarly, using NiMo/γ-Al 2 O 3 along with ethanol as the solvent at 300 °C reportedly led to oil yield of 44 wt% and monomer yield of 18.1 wt% from organosolv lignin. 12 As lignin is a major fraction in the black liquor followed by carbohydrates and soaps (tall oil), the key products expected from the HTL of black liquor are phenols, ketones and hydrocarbons. It is also possible to integrate the HTL process alongside kraft pulp mills, because the feedstock (black liquor) can be obtained from pulp mills directly and the energy required for the HTL process can be recovered from pulp mills by meticulous use of heat exchangers.…”