Impact of moisture content on instant catapult steam explosion pretreatment of sweet potato vine

Background: Lignocellulose originating from renewable and sustainable biomass is a promising alternative resource to produce biofuel. However, the complex component, especially high moisture content, leads to a higher cost of transportation and processing. The instant catapult steam explosion (ICSE) pretreatment can exploit the intracellular water of lignocellulosic materials and convert into vapors leading towards the breakdown of the feedstock during the explosion process. However, it is necessary to study the impact of moisture content on the pretreatment. Results: The sugar yield of wet feedstock after ICSE pretreatment reached 88.05%, which was higher when compared to dried and untreated biomass. The utilization of wet feedstock decreased the production of inhibitor and improved the carbohydrate content in ICSE-treated biomass. There occurred a shrinkage of feedstock after drying process and the mechanical breakage upon ICSE pretreatment. Moreover, not all water was converted into vapor to cause breakage in the lignocellulose. Conclusion: ICSE has shown to be preferably suitable to pretreat wet sweet potato vine with high moisture content, either fresh or soaked biomass that has been dried before. By using these materials, it would have a higher sugar yield and lower inhibitor production after pretreatment. Based on these advantaged aspects of ICSE platform, two potential strategies are proposed to improve the economic and environmental impacts of pretreatment.