The need for clean, alternative energy sources has increased due to the depletion of fossil fuel reserves and rising energy consumption. Saccharification, fermentation, and chemical pretreatment can turn lignocellulosic biomass (LCB), an affordable and renewable resource, into bioenergy potential. Chemical pretreatment is essential to convert LCB into biofuels or biochemicals in later stages. Certain upgraded pretreatments are required to improve LCB accessibility and digestion. Enhancing the hydrolysis of its carbohydrates, such as cellulose and hemicelluloses, is the inevitable of the LCB pretreatment. In order to produce bioproducts, lignocelluloses must have their refractory structure modified. Different pretreatment techniques have been developed to produce bioenergy from LCB. The most current developments in acid, alkaline, organosolv, deep eutectic solvents (DESs), and wet oxidation chemical pretreatment techniques (CPT) are reviewed and discussed. The study aims to increase our understanding of these pretreatment procedures and their potential as environmentally friendly technologies for advancing contemporary biorefineries and the future recommendations were discussed.

Biorefinery, Bioenergy potential, Ligno cellulosic biomass, Pretreatment technology, Upgrade chemical methods

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