Study on adsorption experiment of high fluorine and high COD wastewater by preparing activated carbon with NaOH activation method

LI Lanting; LI Guanxiu; HUANG Peng

doi:10.3969/j.issn.1007-7677.2025.06.006

Abstract：Wastewater containing organic pollutants has poor biodegradability and is difficult to treat,and wastewater containing fluoride is even more difficult to manage.Both of them are highly polluted and difficult to treat wastewater,which causes a threat to the environment and human health.Currently,there is no targeted treatment methods for wastewater containing high concentration of fluoride ions and high concentration of organic pollutants.In this paper,coal-based activated carbon was prepared by NaOH activation method,and the static and dynamic adsorption removal experiments of high fluorine and high COD waster were carried out by using adsorption method to investigate the pore structure and surface properties of activated carbon and the removal effect of activated carbon on heavy metals,fluor-ide ions and COD in wastewater.The results showed that the activated carbon prepared by NaOH activation method has micropores,mesopores and acidic groups,and the activated carbon has good adsorption effect on metal ions,COD and fluoride ions in wastewater.The static adsorption experiment shows that the adsorption of pollutants in wastewater by activated carbon mainly occurs within the first 90 min of contact between carbon wastewater,and then the adsorption capacity decreases significantly,with a saturated adsorption capacity of 90.9 mg/g for COD and 2.44/g for fluoride ions.The dynamic adsorption experiment showed that the activated carbon preferentially adsorbed heavy metal and fluoride ions and the adsorption capacity for COD and fluoride ions was lower than its static adsorption satu-ration capacity,and the COD pollutant penetrated first at about 480 min of operation,and the fluoride ion had also penetrated after 600 min of operation.It is recommended that the activated carbon adsorption column should be regen-erated at 30～60 min of operation in engineering application.