This study aims to valorise the invasive brown alga Sargassum muticum, collected in the Portuguese coast, by converting it into biochar (BC) and activated carbon (AC), which can serve as biosorbents for removing contaminants from water. Effectively managing invasive alien species has become a pressing concern, as they pose significant threats to biodiversity, ecosystems, local economies, and human health in the affected regions. The primary objective is to assess the effectiveness of Sargassum-based adsorbents in removing VLF, the pharmaceutical compound of interest, as well as three different metals: Cr, Li, and Nd. For the metal tests, Nd was selected, as the produced carbon materials demonstrated the highest efficiency in removing this ion.