A Critical Review on Bioethanol and Biochar Production from Lignocellulosic Biomass and Their Combined Application in Generation of High-Value Byproducts

Lignocellulosic biomass materials have gained much attention as sustainable and renewable resources for the production of biofuels and adsorbents due to their high availability and low price. This Review focuses on bioethanol and biochar, both of which have the potential to reduce the waste of resources and increase energy security and ecological sustainability. The procedures for bioethanol and biochar production are presented, especially the challenge in detoxifying fermentation inhibitors in the bioethanol production process. In addition, the effectiveness of combining biochar preparation with the bioethanol production process is introduced. A recent report shows that a self-sufficient system can be established to effectively remove fermentation inhibitors in the bioethanol production process, improve the fermentation environment, and immobilize the fermentative microbes. In addition, various biochar modification methods for application in the removal of fermentation inhibitors in pretreated hydrolysates are proposed. This Review provides the latest research results and will be an important supplement in the field of combination bioethanol and biochar production, especially for the development of detoxification methods to remove fermentation inhibitors in the bioethanol production process.