Pretreatment and hydrolysis of lignocellulosic wastes for butanol production: Challenges and perspectives.

Butanol is acknowledged as a drop-in biofuel that can be used in the existing transportation infrastructure, addressing the needs for sustainable liquid fuel. However, before becoming a thoughtful alternative for fossil fuel, butanol should be produced efficiently from a widely-available, renewable, and cost-effective source. In this regard, lignocellulosic materials, the main component of organic wastes from agriculture, forestry, municipalities, and even industries seems to be the most promising source. The butanol-producing bacteria, i.e., Clostridia sp., can uptake a wide range of hexoses, pentoses, and oligomers obtained from hydrolysis of cellulose and hemicellulose content of lignocelluloses. The present work is dedicated to reviewing different processes containing pretreatment and hydrolysis of hemicellulose and cellulose developed for preparing fermentable hydrolysates for biobutanol production.