Fluorine has a high abundance in natural environment like water and mineral resources. A large amount of acidic fluoride containing wastewater has been produced during the nonferrous metal metallurgy process, which will cause severe environmental pollution and endanger human health if directly discharged. Adsorption method has been widely concerned to treat wastewater due to its advantages of low cost, simple operation, flexible adsorption device and high adsorption capacity. It is suitable for the advanced treatment of fluorine containing wastewater from nonferrous metal beneficiation and metallurgy process. Chitosan has been widely used in the field of water treatment because of its rich amino and hydroxyl groups. In this project, an efficient porous carbon-based fluorine adsorbent was prepared by modified chitosan, aiming to remove acidic high-aluminum and fluorine-containing wastewater produced in the process of aluminosilicate mineral processing and metallurgy. Modification is mainly carried out by loading titanium-based active materials and nitrogen doping. The initial concentration of fluoride, initial pH value of liquid phase and static adsorption time were firstly investigated to determine the saturated adsorption capacity. The adsorption thermodynamics and kinetics analysis were also investigated. Langmuir and Freundlich equation models were selected to fit the isothermal adsorption process. The structure and composition change of the adsorbent were characterized to reveal the selective defluorination mechanism of the modified chitosan. In addition, the prepared fluorine adsorbent was modified for acid resistance to maintain a high adsorption capacity even under the condition of pH&lt;3. The high adsorption performance still maintained above 80% after 5 cycles. This deep defluoridation in acidic system explored in this project is of great research significance for the green beneficiation and metallurgy of nonferrous metal mineral resources.

Investigation on advanced removal of fluoride containing wastewater from metallurgy by titanium modified porous carbon based biomimetic gel

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.