Electrochemical Biorefinery toward Chemicals Synthesis and Bio-Oil Upgrading from Lignin

Recalcitrance and the inherent heterogeneity of lignin structure are the major bottlenecks to impede the popularization of lignin-based chemicals production processes.Recent works suggested a promising pathway for lignin depolymerization and lignin-derived bio-oil upgrading via an electrochemical biorefinery(a process in which lignin valorization is performed via electrochemical oxidation or reduction).This review presents the progress on chemicals synthesis and bio-oil upgrading from lignin by an electrochemical biorefinery,relating to the lignin biosynthesis pathway,reaction pathway of lignin electrochemical conversion,inner-sphere and outer-sphere electron transfer mechanism,basic kinetics and thermodynamics in electrochemistry,and the recent embodiments analysis with the emphasis on the respective feature and limitation for lignin electrochemical oxidative and reductive conversion.Lastly,the challenge and perspective associated with lignin electrochemical biorefinery are discussed.Present-day results indicate that more work should be performed to promote efficiency,selectivity,and stability in pursuing a lignin electrochemical biorefinery.One of the most promising developing directions appears to be integrating various types of lignin electrochemical conversion strategies and other existing or evolving lignin valorization technologies.This review aims to provide more references and discussion on the development for lignin electrochemical biorefinery.

Wood waste biochar promoted anaerobic digestion of food waste:focusing on the characteristics of biochar and microbial community analysis

Anaerobic digestion(AD)has been considered as a promising technique for food waste(FW)recycling.However,the accumulation of volatile fatty acids(VFAs)restricts the stability of anaerobic reactors.The present study investigated the use of biochar produced at different conditions(750℃-30 min,750℃-60 min,750℃-120 min,550℃-60 min,650℃-60 min,850℃-60 min,950℃-60 min)for enhancing the AD of FW.Batch experiments showed that all the biochar increased the methane production rates and biochar obtained at 750℃-60 min resulted in the highest enhance-ment by 21.5%.It was further showed surface oxygen-containing functional groups and graphitization degree of biochar were the critical factors for improving methane production.Microbial analysis showed that biochar addi-tion formed different microbial communities,and Methanosaeta,Romboutsia,and norank_f_Anaerolineaceae were enriched,which might be correlated with direct interspecies electron transfer(DIET).This research showed biochar could enhance the AD of FW and also revealed the main characteristics of biochar relating with the enhancement of AD.

Urgently reveal longly hidden toxicant in a familiar fabrication process of biomass-derived environment carbon material

Biomass-derived N-doped carbon(BNC)is an important environmental material and widely used in the fields of water purification and soil remediation.However,the toxicant in the commonly used synthesis process of BNC materials have been largely ignored.Herein,we firstly report the presence of a highly toxic by-product(KCN)in the activation process of BNC materials consequential of the carbothermal reduction reaction.Because this carbothermal reduction reaction also regulates the N-doping and pore development of BNC materials,the KCN content directly relates with the properties of BNC material properties.Accordingly,a high KCN content(-611 mg)can occur in the production process of per g BNC material with high specific surface area(-3600 m^2/g).Because the application performance of BNC material is determined by the surface area and available N doping,therefore,production of a BNC material with high performance entails high risk.Undoubtedly,this study proves a completely new risk recognition on a familiar synthesis process of biomass-based material.And,strict protective device should be taken in fabrication process of biomass-derived carbon material.