Studies on evaluation of pretreatment efficiency of surfactant mediated ultrasonic pretreatment of Sargassum tennerimum (marine macroalgae) for achieving profitable biohydrogen production

Growing energy demand is inevitable in the future, due to increased commercialization and industrialization. Biohydrogen production from renewable biomass is considered as clean energy technology and, in this study, the feasibility of using Sargassum tennerimum as a renewable energy source has been attempted. Pretreatment using sonication pretreatment (ST) and surfactant Dioctyl sodium sulphosuccinate (DOSS) mediated ultrasonic pretreatment (DOSSSP) were investigated and the optimized pretreatment time and sonication power, respectively, were 30 and 200W for ST. DOSS dosage of 0.005 g/g TS was found to be optimum for DOSSSP with the corresponding maximum of 2600 mg/L and 27.36% respectively for sCOD (Soluble chemical oxygen demand) release and COD (Chemical oxygen demand) solubilization percentage. Biohydrogen assay analysis of the pretreated algal biomass was carried out and 86 mL/g COD of maximum biohydrogen production was achieved for DOSSSP pretreated sample than ST and control owing to higher COD solubilization percentage, carbohydrate and protein release. Energy analysis was performed to test the economic viability of the pretreatment process. This analysis showed that the maximum net positive energy of 0.0407 and energy ratio of 2.43 was obtained for DOSSSP revealing its economic viability. This study also reveals that macroalgae Sargassum tennerimum could be a sustainable renewable energy source for biohydrogen production as it is abundant throughout the year. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.