Emerging materials and pretreatment strategies in anaerobic digestion for biogas production: A review on recent advances, limitations, and future perspectives

Anaerobic co-digestion (AcoD) and reliable pretreatment methods are highly beneficial to valorizing waste into valuable biogas production because of the balanced substrate stoichiometry and sufficient recalcitrance. In this regard, materials science is illuminating contemporary research to facilitate effective biomass conversion and biogas generation. The application of materials science in the bioenergy industry is believed to enhance biogas yield significantly while minimizing detrimental effects on the environment and the economy. In this review article, the mechanisms and typical properties of different materials, including MXene, carbon quantum dots (CQDs), graphene, nanomaterials, biocarbon, and iron conductive materials (CMs), were thoroughly investigated. A diverse array of ecological and economic perspectives in the biogas sector were elucidated. Given the potential of case studies in comprehending the current situation, a detailed discussion of anaerobic digestion (AD) and biogas production worldwide was highlighted. The latest advancements in pretreatment methods—biological hydrolysis, steam explosion, and microaeration—were discussed. A comparative bibliographic study over the last decade is more beneficial, and this review briefly examined the frequency of documents in relation to the sustainable development goals (SDGs). Finally, the key research gaps and advancements in the AD and biogas field through machine learning (ML) models were emphasized. • Recent trends, challenges, and future perspectives of pretreatments are emphasized. • Carbon quantum dots to conductive materials for biogas production are explored. • Sustainable development goals are discussed by monitoring anaerobic digestion. • The review signifies challenges and advancements of machine learning models. • Comparative bibliography and biomass consumption in biogas are investigated.