Metal impregnate on activated carbon fiber for SO2 gas removal: Assessment of pore structure, Cu supporter, breakthrough, and bed utilization

In this study, a high-efficiency SO2 adsorbent was manufactured using activated carbon fibers (ACFs) into which a Cu supporter was introduced. Carbon fibers were obtained by subjecting a Lyocell fiber to a flame-retardant treatment and carbonization process. A high specific surface area and a uniform microporous structure were obtained using KOH activation to improve the SO2 adsorptivity. After activation, a solution of Cu(NO3)(2)center dot 3H(2)O was used as a chemical agent to impregnate the Cu supporter. As a result, we observed micropores and mesopores in the ACFs and even diffusion of the Cu supporter over the surfaces of the ACFs. After introducing the Cu supporter, the specific surface area and the percentage of micropores increased by 15% or more, and the SO2 adsorptivity increased by 180% or more in comparison to the ACFs without Cu supporter. The SO2 adsorptivity is thought to have been improved as a result of the synergetic effect of physical adsorption by the micropores and mesopores, the specific surface area developed by the effect of the transition metal while introducing the Cu supporter, and the chemical adsorption reaction of SO2 gas by the Cu supporter. (C) 2016 Elsevier B.V. All rights reserved.