Efficient Ni‐Cu/AC Bimetal Catalyst for Hydrogenolysis of Lignin to Produce High‐Value‐Added Chemicals

Abstract

Efficient depolymerization of natural lignin is the key step to convert lignin to sustainable and added‐value chemicals. In this paper, a carbon‐supported Ni‐Cu bimetallic catalyst was developed for the hydrogenation of poplar lignin and β‐O‐4 model compounds. Five Ni‐Cu bimetallic catalysts were prepared by immobilizing Ni and Cu at fixed Ni loading (5%) and varied Cu loading (0%, 5%, 10%, 20%, 30%) on activated carbon (AC). All the Cu‐Ni/AC bimetal catalysts exhibited higher catalytic activity than either Ni/AC or Cu/AC catalysts. 5Ni‐5Cu/AC gave the highest bio‐oil yield of 40.2 wt% for the hydrogenation of. poplar lignin. The XPS, XRD, and HRTEM characterization of the catalysts showed that elemental copper and Cu‐Ni alloy were formed on the surface of 5Ni‐5Cu/AC catalyst, which could promote the efficient depolymerization of lignin into phenolic monomers. The possible mechanism for the lignin depolymerization was also studied and proposed based on the β‐O‐4 bond model compounds. This study provides a viable strategy for the conversion of lignin into added‐value chemicals with low cost catalyst.

Carbon-Based Nanocatalysts (CnCs) for Biomass Valorization and Hazardous Organics Remediation

“…More specifically, Cu is susceptible to electrons provided by Ni, thus improving the dispersion of Cu nanoparticles and their number on the catalyst surface. Simultaneously, Cu can change the crystal structure of Ni and effectively reduce the excessive hydrogenation products [ 199 ].…”

How to Reduce Char Formation in the Lignin Degradation Process: A Review

“…Lignin is also the second most abundant biomass resource species in nature, so the degradation of lignin to aromatic monomers and as an alternative option when petroleum is depleted has great research value. [1] Many methods such as pyrolysis, [2][3][4] oxidation, [5][6][7] reduction, [8][9] acid catalysis, [10][11] base catalysis, [12][13] metal (single metal, [14][15] noble metal [16][17] and bimetal [18] ) catalysis and organic-inorganic catalysis [19][20] has been applied to degrade lignin into bio-oil or small molecule. However, in the process of depolymerization, the intermediate body polymerizes to form stable carbon, [21] as shown in Figure 1.…”

Cobalt-Doped Ultrathin Ni(OH)2 Nanosheet Array @NiCo Alloy toward an Efficient Oxygen Evolution Reaction and the Electrooxidation of Phenoxyethanol

“…26,27 On the other hand, it can also supply a new way to utilize the huge amount of lignin. 14,28,29 However, in the LAWE, due to the large molecular weight and complex structure of lignin, how to improve the oxidation efficiency and reveal the electrooxidation mechanism remains challenging. 23,30,31 A lignin model compound, which contains the main structure of lignin, has been used to investigate the reaction mechanism of lignin.…”

“…Lignin-assisted water electrolysis (LAWE) has double advantages. On the one hand, LAWE can reduce the anode potential and electricity consumption for hydrogen production. , On the other hand, it can also supply a new way to utilize the huge amount of lignin. ,, However, in the LAWE, due to the large molecular weight and complex structure of lignin, how to improve the oxidation efficiency and reveal the electrooxidation mechanism remains challenging. ,, A lignin model compound, which contains the main structure of lignin, has been used to investigate the reaction mechanism of lignin. Phenoxyethanol, as a typical kind of lignin model compound, contains β-O-4 structure and alcoholic hydroxyl, which are the most abundant linkage structures in lignin. , Thus, phenoxyethanol can be applied to investigate the electrooxidation mechanism of lignin quantitatively.…”