title: Application of dissolved air flotation on separation of waste plastics ABS and PS.
abstract: The aim of this research was to separate waste plastics acrylonitrile butadiene styrene (ABS) and polystyrene (PS) by dissolved air flotation in a self-designed dissolved air flotation apparatus. The effects of wetting agents, frother, conditioning time and flotation time on flotation behavior of waste plastics ABS (w-ABS) and PS (w-PS) were investigated and the optimized separation conditions were obtained. The results showed that when using 25 mgL(-1) tannic acid, 5 mgL(-1) terpineol, 15 min conditioning time and 15 min flotation time, mixtures of w-ABS and w-PS were separated successfully by dissolved air flotation in two stages, the results revealed that the purity and recovery rate of w-PS in the floated products were 90.12% and 97.45%, respectively, and the purity and recovery rate of w-ABS in the depressed products were 97.24% and 89.38%, respectively. Based on the studies of wetting mechanism of plastic flotation, it is found that the electrostatic force and hydrophobic attraction cannot be the main factor of the interaction between wetting agent molecules and plastic particles, which can be completed through water molecules as a mesophase, and a hydrogen bonding adsorption model with hydration shell as a mesophase was proposed.
authors.affiliation: School of Chemistry and Chemical Engineering, Key Laboratory of Resource Chemistry of Nonferrous Metals, Ministry of Education, Central South University, Changsha, 410083 Hunan, China. huiwang1968@163.com
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Xiao-Lei
authors.initials: XL
authors.lastname: Chen
authors.forename: Yang
authors.initials: Y
authors.lastname: Bai
authors.forename: Chao
authors.initials: C
authors.lastname: Guo
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000327:Adsorption; D000388:Air; D002070:Butadienes / Q000737:chemistry; D004867:Equipment Design; D057927:Hydrophobic and Hydrophilic Interactions; D008956:Models, Chemical; D010316:Particle Size; D010969:Plastics / Q000737:chemistry; D011137:Polystyrenes / Q000737:chemistry; D012037:Refuse Disposal / Q000295:instrumentation / Q000379:methods*; D055672:Static Electricity; D013997:Time Factors; D014906:Wetting Agents / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D002070:Butadienes; D010969:Plastics; D011137:Polystyrenes; D014906:Wetting Agents; C024636:ABS resin