More Ganesh Sunil, Singh Bhupendra Pratap, Bal Rajaram, Srivastava Rajendra
Catalysis Research Laboratory, Department of Chemistry, Indian Institute of Technology Ropar, Rupnagar, Punjab 140001, India.
Nanocatalysis Area Conversion and Catalysis Division, CSIR-Indian Institute of Petroleum, Dehradun 248005, India.
Inorg Chem. 2023 Aug 14;62(32):13069-13080. doi: 10.1021/acs.inorgchem.3c01920. Epub 2023 Aug 3.
The hydrogenation of lignin-derived phenolics to produce valuable chemicals is a promising but challenging task. This study successfully demonstrates the use of sustainable transition metal-based catalysts to hydrogenate lignin-derived phenolics. A defect-induced oxygen vacancy containing H-NbO prepared from commercial NbO was employed as a catalyst. H-NbO exhibited higher oxygen vacancies (158.21 μmol/g) than commercial NbO (39.01 μmol/g), evaluated from O-TPD. Upon supporting 10 wt % Ni, a Ni/NiO interface was formed over H-NbO, which was intrinsically active for the hydrogenation of phenolics. 10Ni/H-NbO exhibited a two-fold increase in activity than 10Ni/NbO, achieving >99% eugenol conversion and affording ∼94% 4-propyl cyclohexanol selectivity, wherein ∼63% eugenol conversion and ∼73% 4-propyl cyclohexanol selectivity were obtained over 10Ni/NbO. The Ni/NiO formation was confirmed by X-ray photoelectron spectroscopy, HR-TEM, and H-TPR analysis, while the oxygen vacancies were verified by Raman spectroscopy and O-TPD analysis. The resulting interface enhanced the synergy between Ni and H-NbO and facilitated hydrogen dissociation, confirmed by H-TPD. Remarkably, 10Ni/H-NbO maintained its catalytic activity for five tested cycles and demonstrated exceptional activity with various phenolics. Our findings highlight the potential of a sustainable transition metal catalyst for the hydrogenation of lignin-derived phenolic compounds, which could pave the path to producing valuable chemicals in an environmentally friendly manner.
将木质素衍生的酚类化合物加氢以生产有价值的化学品是一项前景广阔但具有挑战性的任务。本研究成功展示了使用可持续的过渡金属基催化剂对木质素衍生的酚类化合物进行加氢。采用由商用NbO制备的含缺陷诱导氧空位的H-NbO作为催化剂。通过O-TPD评估，H-NbO的氧空位（158.21 μmol/g）高于商用NbO（39.01 μmol/g）。负载10 wt%的Ni后，在H-NbO上形成了Ni/NiO界面，该界面对于酚类化合物的加氢具有内在活性。10Ni/H-NbO的活性比10Ni/NbO提高了两倍，丁香酚转化率>99%，4-丙基环己醇选择性约为94%，而在10Ni/NbO上丁香酚转化率约为63%，4-丙基环己醇选择性约为73%。通过X射线光电子能谱、高分辨透射电子显微镜和H-TPR分析证实了Ni/NiO的形成，同时通过拉曼光谱和O-TPD分析验证了氧空位。H-TPD证实，所得界面增强了Ni与H-NbO之间的协同作用并促进了氢解离。值得注意的是，10Ni/H-NbO在五个测试循环中保持了其催化活性，并对各种酚类化合物表现出优异的活性。我们的研究结果突出了可持续过渡金属催化剂对木质素衍生酚类化合物加氢的潜力，这可能为以环境友好方式生产有价值的化学品铺平道路。
