645-56-7Relevant articles and documents
Controlled lignosulfonate depolymerization: Via solvothermal fragmentation coupled with catalytic hydrogenolysis/hydrogenation in a continuous flow reactor
Al-Naji, Majd,Antonietti, Markus,Brandi, Francesco
supporting information, p. 9894 - 9905 (2021/12/24)
Sodium lignosulfonate (LS) was valorized to low molecular weight (Mw) fractions by combining solvothermal (SF) and catalytic hydrogenolysis/hydrogenation fragmentation (SHF) in a continuous flow system. This was achieved in either alcohol/H2O (EtOH/H2O or MeOH/H2O) or H2O as a solvent and Ni on nitrogen-doped carbon as a catalyst. The tunability according to the temperature of both SF and catalytic SHF of LS has been separately investigated at 150 °C, 200 °C, and 250 °C. In SF, the minimal Mw was 2994 g mol-1 at 250 °C with a dispersity (?) of 5.3 using MeOH/H2O. In catalytic SHF using MeOH/H2O, extremely low Mw was found (433 mg gLS-1) with a ? of 1.2 combined with 34 mg gLS-1. The monomer yield was improved to 42 mg gLS-1 using dual catalytic beds. These results provide direct evidence that lignin is an unstable polymer at elevated temperatures and could be efficiently deconstructed under hydrothermal conditions with and without a catalyst. This journal is
Rational design of oligomeric MoO3 in SnO2 lattices for selective hydrodeoxygenation of lignin derivatives into monophenols
Diao, Xinyong,Ji, Na,Jia, Zhichao,Jiang, Sinan,Li, Tingting,Liu, Caixia,Liu, Qingling,Lu, Xuebin,Song, Chunfeng,Wang, Zhenjiao
, p. 234 - 251 (2021/08/19)
Novel Mo-Sn bimetallic oxide catalysts with highly dispersed oligomeric MoO3 in SnO2 lattices, which were synthesized by the co-precipitation method and pretreated by anhydrous ethanol, were first employed in the hydrodeoxygenation of various lignin derivatives to produce monophenols with high activity and selectivity. In comparison with the pure α-MoO3 and the previous reported catalysts, the α-2Mo1Sn exhibited superior activity in the hydrodeoxygenation of guaiacol, with full conversion and 92.5% phenol yield at 300 °C under 4 MPa initial H2 pressure in n-hexane for 4 h. According to comprehensive characterizations and catalytic measurements, the excellent performance of α-2Mo1Sn was ascribed to the formation of abundant Sn-O-Mo-OV interfacial sites, which possessed strong Mo-Sn interaction with enhanced surface area, electron-donating group binding ability, Lewis acidity, and redox ability. It was demonstrated that over the present α-2Mo1Sn catalyst system, the Sn-O-Mo-OV interfacial sites could greatly facilitate the adsorption and activation of Caromatic-OCH3 and Caromatic-CH3 bonds, and thus significantly promote the demethoxylation and demethylation reaction to produce phenol. This work figures out the rational design of MoO3-based catalyst and displays a clear potential for the selective hydrodeoxygenation of lignin derivatives into monophenols.
Photocatalytic transfer hydrogenolysis of aromatic ketones using alcohols
Gao, Zhuyan,Han, Jianyu,Hong, Feng,Lei, Lijun,Li, Hongji,Liu, Huifang,Luo, Nengchao,Wang, Feng
, p. 3802 - 3808 (2020/07/09)
A mild method of photocatalytic deoxygenation of aromatic ketones to alkyl arenes was developed, which utilized alcohols as green hydrogen donors. No hydrogen evolution during this transformation suggested a mechanism of direct hydrogen transfer from alcohols. Control experiments with additives indicated the role of acid in transfer hydrogenolysis, and catalyst characterization confirmed a larger number of Lewis acidic sites on the optimal Pd/TiO2 photocatalyst. Hence, a combination of hydrogen transfer sites and acidic sites may be responsible for efficient deoxygenation without additives. The photocatalyst showed reusability and achieved selective reduction in a variety of aromatic ketones.
