Production and characterization of hydrothermally processrd solid bioenergy from an invasive species

Invasive alien species (IAS) are one of the most serious environmental concerns for native biodiversity, as they can alter how the ecosystem functions through species homogenization. Invasive species can affect human health, disrupt ecosystem process, economic damage to agriculture. The conversion of invasive species through hydrothermal carbonization process can reduce the negative impact of invasive species. The objective of this study was to produce and characterize hydrochar as solid bio-energy derived from the invasive species Sphagneticola trilobata (ISST), an invasive plant species, specifically through hydrothermal carbonization. This technology can convert invasive species into biofuel by reducing their negative impact on the environment. The effect of different factors, namely temperature and reaction time towards the hydrochar yield (%) was optimized by central composite design (CCD) using statistical response surface methodology (RSM). Here the optimized conditions for hydrochar production have been identified. The optimized temperature was 180.31 °C and the time was 2.23 hours. The best yield of the hydrochar was 51.54%. To verify the hydrochar as an energy material, the physicochemical, structural and morphological properties were found using SEM, FTIR, TGA, elemental and proximate analysis. The calorific value of hydrochar increased from the calorific value of 13.41 MJ/Kg of Sphagneticola trilobata biomass to 17.03 MJ/Kg. The amounts of sulfur (S) and ash reduced dramatically. Moreover, a greater carbon content was present in the green biomass than oxygen content. Consequently, it is an advantageous technology for improving the characteristics of biomass of invasive species to hydrochar as fuel for energy generation.