Green Technology for Bioadsorption of Petroleum Crude Oil in Seawater

Phyco-remediation is a promising method for pollution reduction, offering advantages over other approaches. Dissolved crude oil fractions are highly toxic to marine life. The contribution of macroalgae (Sargassum sp.and Corallina sp.) as bio-adsorbents for the removal of water-soluble fractions (WSFs) of crude oil at different times and concentrations was estimated. The characterization of algae was analyzed using BET, SEM, FTIR and zeta analysis. The best value of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) adsorption at a concentration of 25% for the two algae after 10 days. The same descending order rate of adsorption was found in PAHs >Light n-alkanes >Heavy n-alkanes. Sargassum sp.was the best to adsorb n-alkanes, while Corallina sp. was the best to adsorb PAHs. The BET surface area of the biosorbent algae was less than 0.6 m2/g. SEM showed that the surface algal cells became irregular and twisted due to the adsorption of contaminants. These algal cells exhibit different chemical groups present on seaweed surfaces that take part in crude oil adsorption as shown by FTIR. The zeta potential revealed that the cell of Sargassum sp.has a more negative surface than Corallina sp.. The present study indicates that seaweed has strong biosorbent potential, making it a cost-effective, efficient, and environmentally friendly solution for bioremediation.