Lignin-Derived\nMagnetic Activated Carbons for Effective\nMethylene Blue Removal

Abstract

Large-scale environmental remediation of polluted water\nrequires\nan effective and recyclable adsorbent produced from an abundant, low-cost,\nand renewable feedstock via a simple processing procedure. In this\nwork, we demonstrate that lignin-derived magnetic activated carbons\n(mACs) uniquely satisfy these five criteria for (i) high-performance\nadsorption, (ii) high regeneration efficiency, (iii) feedstock economic\nand environmental viability, (iv) single-step processing, and (v)\nlarge-scale production. The mACs are synthesized via an efficient\ncocarbonization and activation with simultaneous impregnation of ferric\nsulfate. The Langmuir model closely fits the adsorption of methylene\nblue (MB) by mACs within the temperature range of 298–323 K,\nwhere the adsorption capacity increases as temperature increases.\nThis capacity increased from 55.0 mg g^–1 to 220.2\nmg g^–1 with the presence of magnetic nanoparticles.\nIn addition, the magnetite nanoparticles on the activated carbon surface\nsignificantly improve its recycling ability with a removal percentage\nabove 95% after four cycles for 5:1 mAC.