Adsorption Of Humic Acid And Perfluorooctanoic Acid Onto Amino-modified Porous Carbon-based Materials

Adsorption of HA onto amino-modified mesoporous carbon compare to mesoporous carbon and adsorption of PFOA onto different calcination temperatures of amino-modified biochar compare to pristine biochar were investigated.The obtained adsorbents were characterized by FT-IR,EA,N2 adsorption and Potentiometric acid-base titration.Based on the adsorpion and characterization results,the mechanism of HA and PFOA onto the amino-modified porous carbon-based materials were discussed.The results were summarized as follows:Use APTMS can grafted amino functional groups onto carbon-based materials successfully,which enhanced adsorbents'alkalinity.Moreover,this method has universal applicability to synthetic mesoporous carbon and biochar from different sources.Amino-modified porous carbon-based materials basic maintain the original structural characteristics,the adsorption performance and removal efficiency to HA and PFOA was significantly enhanced.The adsorption mechanism was mainly electrostatic interaction.The very strong pH dependence on adsorption to amino-modified porous carbon-based materials indicates the importance of electrostatic interactions.With increasing pH,the degree of protonation of the adsorbents amino groups decreases,thereby reducing available cationic sites for adsorption of HA and PFOA.Adsorption of HA and PFOA onto amino-modified porous carbon-based materials were dominated by chemical adsorption,and these adsorbents had good recycling ability,which was a kind of green and environment-friendly adsorption material.