High-quality bio-oil from one-pot catalytic hydrocracking of kraft lignin over supported noble metal catalysts in isopropanol system

Effect of Solvent, Role of Formic Acid and Rh/C Catalyst for the Efficient Liquefaction of Lignin

“…Also, Rh and other noble metal catalysts are known for hydrogenation of aromatic rings, thus resulting in more aliphatic alcohols or hydrocarbons. [38,48] In the present study, we also found the formation of more types of aliphatic compounds using Rh/C alone as a catalyst compared to the FA catalyst, as shown in Figure S7-S9; ESI, the GC-MS analysis confirms the formation of an aliphatic compound such as 4-ethyl-2-methoxyphenol, 2-methoxy-4-propylphenol, homovanillic acid, etc.…”

Correlation between Liquid Product Distribution and H2 Selectivity in Lignin Depolymerization

“…The catalytic process contributed to upgrading the phenols into conventional transport alkane fuels, which had the advantage of a higher heating value (HHV) [10,11]. A similar conclusion was also derived in previous studies in which the common noble metals (Pd, Pt, Ru, Rh) supported on active carbon were applied in the hydrocracking of kraft lignin [12]. Instead, aromatics were rarely obtained due to saturation of the phenolic rings resulting from the catalytic hydrodeoxygenation process.…”

“…This seems due to the low H 2 concentrations causing chemisorption of isopropanol on the catalyst surface [26]. Isopropanol turns unstable and converts to aliphatic compounds under high-temperature conditions [12]. When the ratio of isopropanol to water decreased from 6:4 to 3:7 (H 2 selectivity from 88 to 80 %; H 2 yield from 11.83 to 4.43 mmol), the hydrogenated cyclics continued to decrease until they were undetectable.…”

“…However, the aromatics (C [6][7][8][9][10][11][12][13][14][15][16] ) increased steadily and became the main component of the liquid products instead of the aliphatic compounds, during the process of decreasing H 2 selectivity (from 81 to 49 %) and H 2 yield (from 14.52 to 4.11 mmol). Compared with the H 2 selectivity and yield ob- tained without formic acid, the former constituted the main change.…”

Effects of the novel catalyst Ni–S2O82−–K2O/TiO2on efficient lignin depolymerization

“…† The product distribution was measured and the HHV of the liquid product was analyzed. 45,46 The monomers were investigated by GC-MS and GC. The details of the above characterization methods are also shown in the ESI.…”