title: Removal of mercaptans from a gas stream using continuous adsorption-regeneration.
abstract: The removal of the mercaptan, 1-methyl-1-propanethiol, from aqueous solutions using a non-porous, electrically conducting carbon-based adsorbent (Nyex 1000) was investigated. The adsorption process was found to be rapid (equilibrium capacity achieved within 5 minutes) with low adsorptive capacity (of the order of 0.4 mg g(-1)) when compared with activated carbon. Electrochemical regeneration of the Nyex 1000 in a simple divided electrochemical cell within a sequential batch treatment unit restored 100% of the adsorbent's adsorptive capacity using treatment times as low as 20 minutes by passing a current of 0.5 A. The sorptive characteristics of a Nyex-water slurry were also modelled and investigated both in a bubble column and in a continuous adsorption-regeneration treatment system. It was demonstrated that the continuous removal-destruction system could achieve a step reduction in challenge gas concentration of approximately 75% for a period of 35 minutes with a current of 5 Amps. This was attributed to mass transfer enhanced by a combination of adsorption and chemical reaction with free chlorine species generated in the electrochemical process.
authors.affiliation: The University of Manchester, Oxford Road, Manchester M13 9PL, UK. Michael.Conti-Ramsden@postgrad.manchester.ac.uk
authors.forename: M G
authors.initials: MG
authors.lastname: Conti-Ramsden
authors.forename: H M A
authors.initials: HM
authors.lastname: Asghar
authors.forename: S N
authors.initials: SN
authors.lastname: Hussain
authors.forename: E P L
authors.initials: EP
authors.lastname: Roberts
authors.forename: N W
authors.initials: NW
authors.lastname: Brown
mesh_terms: D000327:Adsorption; D000393:Air Pollutants / Q000737:chemistry / Q000302:isolation & purification; D002606:Charcoal / Q000737:chemistry; D004563:Electrochemistry; D013438:Sulfhydryl Compounds / Q000737:chemistry* / Q000302:isolation & purification; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D000393:Air Pollutants; D013438:Sulfhydryl Compounds; D014874:Water Pollutants, Chemical; D002606:Charcoal