TY - JOUR
T1 - Hydrogen gas-free processes for single-step preparation of transition-metal bifunctional catalysts and one-pot Γ-valerolactone synthesis in supercritical CO 2 -ionic liquid systems
AU - Guo, Haixin
AU - Hiraga, Yuya
AU - Qi, Xinhua
AU - Smith, Richard Lee
N1 - Funding Information:
The authors gratefully acknowledgement the financial support by JSPS Grant in Aid Scientific Research (B) , contract No. 25289272 and JSPS Grant in Aid Scientific Research (B) No. 16H04549 (Japan). This work was also supported by funding from Tohoku University Center for Gender Equality Promotion (TUMUG).
Publisher Copyright:
© 2018
PY - 2019/5
Y1 - 2019/5
N2 - Hydrothermal carbonization of glucose (180 °C, 4 h) with 5-sulfosalicylic acid and nickel or copper sulfate afforded transition-metal (Ni/NiO, Cu/CuO) functional carbon (FC) catalysts in a single-step without hydrogen gas. Hydrogenation of levulinic acid to γ-valerolactone (GVL) in supercritical carbon dioxide (scCO 2 )-ionic liquid ([BMIM]Cl) systems with formic acid as H-donor source and Ni/NiO-FC catalysts gave 97% GVL yields (170 °C, 3 h). The Ni/NiO-FC catalysts (d = 50 to 200 nm) had well-dispersed Ni/NiO particles (<5 nm) with –SO 3 H, COOH and phenolic −OH functional groups; Ni/NiO-FC catalysts were more effective than Cu/CuO-FC catalysts. Ni/NiO-FC catalysts were active for conversion of substrates (ethyl levulinate, fructose, cellobiose or cellulose) to respective products (GVL, 5-HMF, sugars). The role of scCO 2 in the reaction system is one of improving mass transport and suppressing side-reactions via GVL product removal. Proposed methods for catalyst synthesis and substrate hydrogenation do not require hydrogen gas and are widely applicable to processing biomass.
AB - Hydrothermal carbonization of glucose (180 °C, 4 h) with 5-sulfosalicylic acid and nickel or copper sulfate afforded transition-metal (Ni/NiO, Cu/CuO) functional carbon (FC) catalysts in a single-step without hydrogen gas. Hydrogenation of levulinic acid to γ-valerolactone (GVL) in supercritical carbon dioxide (scCO 2 )-ionic liquid ([BMIM]Cl) systems with formic acid as H-donor source and Ni/NiO-FC catalysts gave 97% GVL yields (170 °C, 3 h). The Ni/NiO-FC catalysts (d = 50 to 200 nm) had well-dispersed Ni/NiO particles (<5 nm) with –SO 3 H, COOH and phenolic −OH functional groups; Ni/NiO-FC catalysts were more effective than Cu/CuO-FC catalysts. Ni/NiO-FC catalysts were active for conversion of substrates (ethyl levulinate, fructose, cellobiose or cellulose) to respective products (GVL, 5-HMF, sugars). The role of scCO 2 in the reaction system is one of improving mass transport and suppressing side-reactions via GVL product removal. Proposed methods for catalyst synthesis and substrate hydrogenation do not require hydrogen gas and are widely applicable to processing biomass.
KW - Hydrogenation catalyst
KW - Hydrothermal carbonization
KW - Levulinic acid
KW - Platform chemicals
KW - γ-Valerolactone
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U2 - 10.1016/j.supflu.2018.11.010
DO - 10.1016/j.supflu.2018.11.010
M3 - Article
AN - SCOPUS:85056810079
VL - 147
SP - 263
EP - 270
JO - Journal of Supercritical Fluids
JF - Journal of Supercritical Fluids
SN - 0896-8446
ER -