Suppressing inhibitory compounds by nanomaterials for highly efficient biofuel production: A review

With the rapid increase in the global population, domestic and industrial energy consumption is rising at its peak, resulting in the incessant depletion of fossil fuels such as coal, oil and gas; thus, entailing the development of sustainable technologies based on renewable raw materials. Biofuels appear to be an ideal sustainable solution that could help meet future energy supply demands while also contributing to a reduction in greenhouse gas emissions. However, the most significant hurdle in the effective production and utilization of biofuels is the formation of inhibitory compounds such as aliphatic acids, phenolic substances, ketones, alcohols and furan derivatives during the pretreatment and conversion procedure, which results in lower cell density, prolonged microbial lag time and hinders the effective production of biofuels. To address these challenges, nanomaterials are primarily utilized in biofuels production, which enhances the performance of bioprocesses used during the biomass conversion to biofuel by efficiently suppressing the inhibitory compounds formed during the conversion procedure, thus resulting in enhanced biofuel yield. This review is intended to give a brief about the several recent advances made in the utilization of various kind of nanomaterials for suppressing the inhibitory compounds of biofuel production such as bioethanol, biohydrogen and biodiesel under specific conditions. Furthermore, the role of nano-immobilized biocatalysts in suppressing inhibitory compounds has been addressed, with an emphasis on the safety issues and limitations associated with the utilization of nanomaterials in the current approach.