title: Enhancing the adsorption of vapor-phase mercury chloride with an innovative composite sulfur-impregnated activated carbon.
abstract: Mercury chloride (HgCl(2)) is the major mercury derivate emitted from municipal solid waste incinerators, which has high risk to the environment and human health. This study investigated the adsorption of vapor-phase HgCl(2) with an innovative composite sulfurized activated carbon (AC), which was derived from the pyrolysis, activation, and sulfurization of waste tires. The composite sulfur-impregnation process impregnated activated carbon with aqueous-phase sodium sulfide (Na(2)S) and followed with vapor-phase elemental sulfur (S(0)). Thermogravimetric analysis (TGA) was applied to investigate the adsorptive capacity of vapor-phase HgCl(2) using the composite sulfurized AC. The operating parameters included the types of composite sulfurized AC, the adsorption temperature, and the influent HgCl(2) concentration. Experimental results indicated that the sulfur-impregnation process could increase the sulfur content of the sulfurized AC, but decreased its specific surface area. This study further revealed that the composite sulfurized AC impregnated with aqueous-phase Na(2)S and followed with vapor-phase S(0) (Na(2)S+S(0) AC) had much higher saturated adsorptive capacity of HgCl(2) than AC impregnated in the reverse sequence (S(0)+Na(2)S AC). A maximum saturated adsorptive capacity of HgCl(2) up to 5236 μg-HgCl(2)/g-C was observed for the composite Na(2)S+S(0) AC, which was approximately 2.00 and 3.17 times higher than those for the single Na(2)S and S(0) ACs, respectively.
authors.affiliation: Institute of Environmental Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan, ROC.
authors.forename: Iau-Ren
authors.initials: IR
authors.lastname: Ie
authors.forename: Wei-Chin
authors.initials: WC
authors.lastname: Chen
authors.forename: Chung-Shin
authors.initials: CS
authors.lastname: Yuan
authors.forename: Chung-Hsuang
authors.initials: CH
authors.lastname: Hung
authors.forename: Yuan-Chung
authors.initials: YC
authors.lastname: Lin
authors.forename: Hsieh-Hung
authors.initials: HH
authors.lastname: Tsai
authors.forename: Yi-Shiu
authors.initials: YS
authors.lastname: Jen
mesh_terms: D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D008627:Mercuric Chloride / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D013455:Sulfur / Q000737:chemistry*; D013499:Surface Properties; D013818:Thermogravimetry
chemical_list: D008627:Mercuric Chloride; D013455:Sulfur; D002244:Carbon