Lignin-derived layered 3D biochar with controllable acidity for enhanced catalytic upgrading of Jatropha oil to biodiesel

Enhancing catalytic activity and pore structure of metal-organic framework-808 via ligand competition for biodiesel production from microalgal lipids at reduced temperatures

Catalysts with hierarchical porous structures and increased active defects play a crucial role in catalyzing the conversion of microalgae lipids. However, the template methods used for pore expansion and the acidification process employed to enhance activity are cumbersome and prone to deactivation. It is necessary to propose a simple and versatile synthetic approach to overcome these challenges. By modulating N,N-dimethylformamide basicity with formic acid, MOF-808 exhibited enhanced coordination of benzene-1,3,5-tricarboxylic acid to Zr-clusters, creating three types of functional defects. These defects increased pore size from 1.63 nm to 5.34 nm and enhanced catalyst acidity by 22.8%, while maintaining high porosity. The active catalytic sites were confirmed to be defect sites (exposed Zr4+) through density functional theory. Compared to regular MOF-808, catalyst MOF-808-3/1 shows enhanced hierarchical porosity and increased acidity, enabling efficient conversions at reduced reaction temperature (100 °C) and pressure (352 kPa) compared to 200 °C and 4036 kPa, respectively.

Review of Advances in the Utilization of Biochar-Derived Catalysts for Biodiesel Production

Biochar, obtained from the thermal decomposition of different biomass sources, can be used in various scientific technologies by virtue of its distinguishing performance. Recent developments in advanced biochar synthesis methods have led to continuous growth in the literature related to bulk biochar products and synthesized biochar substrates. This review specifically summarizes the current advanced methods for the synthesis of functional biochar catalysts and applications in (trans)esterification. Herein, first the method and design of synthesized biochar substrate catalysts are briefly introduced. Second, the applications of these synthesized biochar substrate catalysts upon (trans)esterification are comprehensively discussed. Finally, the current research status and the future perspectives of the synthesized biochar substrate catalyst are presented. It is expected that this summary will provide perspectives and instructions for future work on synthesized biochar catalysts for biodiesel products.

Oxidative C−C bond cleavage of lignin via electrocatalysis

Lignin, which is an important component of biomass in nature and is constantly produced in industry, becomes potential raw material for sustainable production of fine chemicals and biofuels. Electrocatalysis has been extensively involved in the activation of simple molecules and cleavage-recasting of complex scaffolds in an elegant environment. As such, electrocatalytic cleavage of C−C(O) in β-O-4 model molecules of lignin to value-added chemicals has received much attention in recent years. This mini-review introduces various anodes (e.g., Pb, Pt, Ni, Co., and Ir) developed for electro-oxidative lignin degradation (EOLD) under mild conditions. Attention was placed to understand the conversion pathways and involved reaction mechanisms during EOLD, with emphasis on the product distribution caused by different electrodes.