Production, Characterization and Observation of Higher Carbon in Sargassum wightii Biochar From Indian Coastal Waters

Seaweed farming gains significance as a climate resilient strategy owing to significant carbon sequestration potential and research advances to valorize products from seaweed resources. Conversion of seaweeds to biochar enhances further carbon sequestration. In this study Sargassum wightii, belonging to brown algae has been converted into biochar under different conditions of pyrolysis for possible application in aquaculture sector. The prepared biochar was subjected to elemental (CHNS) analysis to assess the nutrient profile. Further, comparative analysis has been done on raw seaweed and biochar based on the structural characterization using SEM, XRD and FTIR spectra. Functional group changes were evidenced from FTIR and XRD spectra, whereas surface modifications were elucidated by SEM analysis. The optimum temperature for biochar pyrolysis of S. wightii to yield higher carbon content has been identified. A significant observation is that seaweeds in Indian coastal waters are capable of higher carbon sequestration than in other waters.