93-51-6Relevant articles and documents
Mild-temperature hydrodeoxygenation of vanillin over porous nitrogen-doped carbon black supported nickel nanoparticles
Nie, Renfeng,Yang, Huanhuan,Zhang, Haifu,Yu, Xiaolong,Lu, Xinhuan,Zhou, Dan,Xia, Qinghua
, p. 3126 - 3134 (2017)
Porous nitrogen-doped carbon black (NCB) was synthesized by facile carbonization of carbon black (CB) coated with polypyrrole (CB@polypyrrole) and used as a support for Ni nanoparticles (NPs). The microstructure, reducibility and crystallinity of the as-synthesized materials were investigated by transmission electron microscopy (TEM), H2-TPR/TPD, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). It was found that surface nitrogen species on NCB significantly promote the decomposition of the nickel precursor and the reduction of nickel oxide, and improve the stability of metallic Ni in ambient atmosphere. In the selective hydrodeoxygenation (HDO) of vanillin in the aqueous phase at low hydrogen pressure (0.5 MPa) and mild temperature (150 °C), Ni/NCB shows much higher activity than N-free catalysts. This is ascribed to the higher reducibility, the lower oxidation state of Ni NPs and the enhanced hydrogen spillover of Ni to the support. Moreover, the Ni/NCB catalyst is relatively cheap and easy to scale-up the production of, thus achieving a low-cost transformation of biomass to bio-oils.
Silica/titania composite-supported NiCo catalysts with combined catalytic effects for phenol hydrogenation under fast and mild conditions
Li, Yucheng,Liu, Jing,He, Jing,Wang, Luying,Lei, Jiandu
, (2020)
The effect of titanium as a promoter for the nickel-cobalt/silica-titania (NiCo/Si-Ti) catalyst in the hydrogenation of phenol was comparatively studied. In the phenol hydrogenation under mild reaction conditions (1 MPa H2 pressure and 100 °C), the Ti-promoter induces the formation of the Coδ??OV?Ti3+ active sites and enhances the hydrogenation activity of the NiCo/Si catalyst to convert phenol to cyclohexanol. The catalytic hydrogenation with the optimal composition of the NiCo/Si-1.0Ti (Si:Ti ratio of 8.5:1) catalyst was completed within 1 h (conversion 98.2 % and selectivity >99 %), which was more efficiently than that with other Ti-doped catalysts and NiCo/Si as baseline, indicating a strong positive synergistic effect between the metal (Ni-Co) and support (Ti-Si) components of the catalyst in this reaction. Additionally, the kinetics, pathway and catalytic mechanism of the hydrogenation of phenol are also examined. Furthermore, the NiCo/Si-1.0Ti catalysts also showed a good performance at reducing the unstable oxygenated compounds in the bio-oil.
In situhydrodeoxygenation of vanillin over Ni-Co-P/HAP with formic acid as a hydrogen source
Duan, Mingxing,Cheng, Qingyan,Wang, Mingming,Wang, Yanji
, p. 10996 - 11003 (2021/03/23)
A new noble metal-free Ni-Co-P/HAP (hydroxyapatite) amorphous alloy catalyst was synthesized by an impregnation-chemical reduction method; the structure and properties of the catalysts were characterized by XRD, SEM, BET, XPS and DSC. Based on the model of the hydrodeoxygenation (HDO) of vanillin to 2-methoxy-4-methylphenol (MMP) with formic acid as a hydrogen source, the catalytic performance of the catalyst was studied. The results found that the Ni-Co-P/HAP catalyst exhibited excellent catalytic activity for thein situHDO reaction of vanillin compared with Ni-P and Ni-Co-P. The conversion of vanillin could be high to 97.86% with MMP selectivity of 93.97% under optimized reaction conditions. In addition, mechanism studies have shown that the side reaction of carbocation and vanillyl alcohol (HMP) condensation can be effectively reduced with increasing the hydrogenation rate, thereby the selectivity of MMP was effectively increased.
Selective upgrading of biomass-derived benzylic ketones by (formic acid)–Pd/HPC–NH2 system with high efficiency under ambient conditions
Chen, Yuzhuo,Chen, Zhirong,Gong, Yutong,Mao, Shanjun,Ning, Honghui,Wang, Yong,Wang, Zhenzhen
, p. 3069 - 3084 (2021/11/16)
Upgrading biomass-derived phenolic compounds provides a valuable approach for the production of higher-value-added fuels and chemicals. However, most established catalytic systems display low hydrodeoxygenation (HDO) activities even under harsh reaction conditions. Here, we found that Pd supported on –NH2-modified hierarchically porous carbon (Pd/HPC–NH2) with formic acid (FA) as hydrogen source exhibits unprecedented performance for the selective HDO of benzylic ketones from crude lignin-derived oxygenates. Designed experiments and theoretical calculations reveal that the H+/H? species generated from FA decomposition accelerates nucleophilic attack on carbonyl carbon in benzylic ketones and the formate species formed via the esterification of intermediate alcohol with FA expedites the cleavage of C–O bonds, achieving a TOF of 152.5 h?1 at 30°C for vanillin upgrading, 15 times higher than that in traditional HDO processes (~10 h?1, 100°C–300°C). This work provides an intriguing green route to produce transportation fuels or valuable chemicals from only biomass under mild conditions.
Method for catalyzing hydrodeoxygenation of vanillin by using MOF-based nano composite material
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Paragraph 0024; 0031-0033; 0040-0042; 0049-0050, (2021/07/31)
The invention discloses a method for catalyzing hydrodeoxygenation of vanillin by using an MOF-based nano composite material, which is characterized in that a UiO-series MOFs material with relatively good hydrothermal stability is used as a carrier and is combined with metal nanoparticles to catalyze hydrodeoxygenation of vanillin. The method solves some problems of a traditional catalyst carrier in the hydrodeoxygenation reaction of vanillin, such as self-sintering, carbon deposition, leaching of active components, and great influence on activity in the reaction process. According to the invention, the active component can be well anchored, the performance of the active component can be promoted, the high yield of the target deoxidation product can be achieved, and the excellent catalysis effect can be achieved.