title: Flotability and flotation separation of polymer materials modulated by wetting agents.
abstract: The surface free energy, surface tension and contact angles were performed to investigate the properties of wetting agents. Adsorption of wetting agents changes wetting behavior of polymer resins. Flotability of polymer materials modulated by wetting agents was studied, and wetting agents change significantly flotability of polymer materials. The flotability decreases with increasing the concentration of wetting agents, and the wetting ability is lignin sulfonate (LS)>tannic acid (TA)>methylcellulose (MC)>triton X-100 (TX-100) (from strong to weak). There is significant difference in the flotability between polymer resins and plastics due to the presence of additives in the plastics. Flotation separation of two-component and multicomponent plastics was conducted based on the flotability modulated by wetting agents. The two-component mixtures can be efficiently separated using proper wetting agent through simple flotation flowsheet. The multicomponent plastic mixtures can be separated efficiently through multi-stage flotation using TA and LS as wetting agents, and the purity of separated component was above 94%, and the recovery was more than 93%.
authors.affiliation: School of Chemistry and Chemical Engineering, Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education, Central South University, Changsha, 410083 Hunan, China. Electronic address: huiwang1968@163.com.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Chemistry and Chemical Engineering, Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Chong-qing
authors.initials: CQ
authors.lastname: Wang
authors.affiliation: School of Chemistry and Chemical Engineering, Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Jian-gang
authors.initials: JG
authors.lastname: Fu
authors.affiliation: School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Guo-hua
authors.initials: GH
authors.lastname: Gu
mesh_terms: D000327:Adsorption; D008031:Lignin; D008422:Materials Testing / Q000379:methods*; D008747:Methylcellulose; D017830:Octoxynol; D011108:Polymers / Q000737:chemistry*; D012037:Refuse Disposal / Q000379:methods*; D013634:Tannins; D014866:Waste Products / Q000032:analysis*; D014906:Wetting Agents / Q000737:chemistry*
chemical_list: D011108:Polymers; D013634:Tannins; D014866:Waste Products; D014906:Wetting Agents; C076151:Kraft lignin; D017830:Octoxynol; D008747:Methylcellulose; D008031:Lignin
keywords: ABS; ABS plastic obtained from air conditioning shell; ABS plastic obtained from television chassis; ABS-air; ABS-tv; Adsorption; Flotability; LS; MC; PC; PC plastic obtained from compact disc; PC plastic obtained from travel cup; PC-cd; PC-cup; PE; PET; PET plastic obtained from drink bottle; PET-dri; PP; PS; PS plastic obtained from car lampshade; PS plastic obtained from cosmetic box; PS-fac; PS-lam; PTFE; PVC; PVC plastic obtained from decorative buckle; PVC plastic obtained from package; PVC plastic obtained from pipe; PVC plastic obtained from rain boot; PVC plastic obtained from water hose; PVC-dec; PVC-hos; PVC-pac; PVC-pip; PVC-sho; Plastics flotation; Plastics recycling; TA; TP; TX-100; WED; WFD; WGD; Wetting agents; acrylonitrile-butadiene-styrene; lignin sulfonate; liquid group of distilled water, ethylene glycol and diiodomethane; liquid group of distilled water, formamide and diiodomethane; liquid group of distilled water, glycerol and diiodomethane; methylcellulose; polycarbonate; polyethylene; polyethylene terephthalate; polypropylene; polystyrene; polytetrafluoroethylene; polyvinyl chloride; tannic acid; terpineol; triton X-100