Polymer-Functionalized Magnetic Activated Carbon as a Novel Adsorbent for the Removal of 2,4,6-Trinitrophenol Ion From Leachate

In this study, powdered activated carbon (PAC) was prepared from barley husk (BH) by the KOH chemical activation method. Then magnetic activated carbon modified by polymers with different functional groups as a novel magnetic adsorbent (mPAC-NH@DTPA-NH 2 ) was successfully synthesized for the removal of 2,4,6-trinitrophenol (TNP) from municipal solid waste (MSW) leachate. The prepared nanocomposite was characterized by using XRD, FTIR FE-SEM, TGA, BET, and VSM analysis. The influences of main parameters such as pH, contact time, adsorbent dose, and initial TNP ion concentration were also investigated. The results indicated that the highest removal rate of TNP under optimum conditions of 100% was observed at pH of 2, an adsorbent dose of 0.15 mg L −1 and a concentration of 10 mg L −1 with a contact time of 60 min. The experimental adsorption data fit well to the pseudo-first-order kinetic model ( R 2 = 0.949) and the Langmuir isotherm equation ( R 2 = 0.962), and the maximum adsorption capacity of TNP was determined to be 123.45 mg g −1 . The thermodynamic studies revealed that the adsorption of TNP ions is exothermic and spontaneous. Moreover, absorbent still had a high removal capacity for TNP after five regeneration cycles. Therefore, mPAC-NH@DTPA-NH 2 had excellent removal efficiency for TNP ions in landfill leachate. At the same time, it could be used as a nonpolluting, outstandingly characteristic adsorbent material.