Potential of Coffee Waste as Nanocomposite and Activated Carbon for Efficiency Removal of PFOA and PFOS in Water

This systematic review examines the potential of coffee waste as a highly promising adsorbent in the water purification industry. Nanocomposite and activated carbon have been identified and tested as effective adsorbents to remove per- and poly-fluoroalkyl substances (PFAS) in the water system. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are part of PFAS contaminants which released into the aquatic environment through the textile, food and beverage, medicine, plumbing, and kitchen utensils industries, which cause bioaccumulation and carcinogenic effect if humans are exposed continuously. Commercial nanocomposite and activated carbon are expensive, thereby the production of nanocomposite and activated carbon from biomass waste can be used as an alternative. Coffee residues are biomass wastes which produced in considerable quantities worldwide. Recently, coffee waste as an adsorbent widely used for efficient wastewater treatment. The systematic review collects information related to the abundance of coffee in Indonesia, potential of coffee waste as an adsorbent, the exposure of PFOA and PFOS in environmental, and in-silico study of coffee’s active compounds against PFOA and PFOS ligands in Human Serum Albumin (HSA). The green synthesis method such as microwave irradiation was used for polymer synthesis based on natural materials Coffee’s active compounds revealed that caffeine and theophylline had the highest binding affinity when interacting with PFOA (-6,0 kcal/mol) while paraxanthine with PFOS (-5,9 kcal/mol) ligands. The green synthesis method was used for polymer synthesis based on natural materials, which are widely used for the synthesis of nanocomposite and activated carbon. The in-silico study showed the potential removal of PFOA and PFOS using coffee waste as an adsorbent.