Comparison of microwave and conduction-convection heating autohydrolysis pretreatment for bioethanol production

This work describes the application of two forms of heating for autohydrolysis pretreatment on isothermal regimen: conduction-convection heating and microwave heating processing using corn stover as raw material for bioethanol production. Pretreatments were performed using different operational conditions: residence time (10-50 minutes) and temperature (160-200°C) for both pretreatments. Subsequently, the susceptibility of pretreated solids was studied using low enzyme loads, and high substrate loads. The highest conversion was 95.1% for microwave pretreated solids. Also solids pretreated by microwave heating processing showed better ethanol conversion in simultaneous saccharification and fermentation process (92% corresponding to 33.8 g/L). Therefore, microwave heating processing is a promising technology in the pretreatment of lignocellulosic materials.Financial support from the Energy Sustainability Fund 2014-05 (CONACYT-SENER), Mexican Centre for Innovation in Bioenergy (Cemie-Bio), Cluster of Bioalcohols (Ref. 249564) is gratefully acknowledged. We also gratefully acknowledge support for this research by the Mexican Science and Technology Council (CONACYT, Mexico) for the Infrastructure Project - INFR201601 (Ref. 269461) and Ciencia Basica-2015-01 (Ref. 254808). This study also was supported by the Secretary of Public Education of Mexico: PROMEP project/103.5/13/6595. The author Alejandra Aguilar also thanks the National Council for Science and Technology (CONACYT, Mexico) for Master fellowship support (grant number: 559391/296768).