title: Flotation separation of polyvinyl chloride and polyethylene terephthalate plastics combined with surface modification for recycling.
abstract: Surface modification with potassium permanganate (KMnO4) solution was developed for separation of polyvinyl chloride (PVC) and polyethylene terephthalate (PET) waste plastics. The floatability of PVC decreases with increasing of KMnO4 concentration, treatment time, temperature and stirring rate, while that of PET is unaffected. Fourier transform infrared (FT-IR) analysis confirms that mechanism of surface modification may be due to oxidization reactions occurred on PVC surface. The optimum conditions are KMnO4 concentration 1.25 mM/L, treatment time 50 min, temperature 60°C, stirring rate 300 r/min, frother concentration 17.5 g/L and flotation time 1 min. PVC and PET with different particle sizes were separated efficiently through two-stage flotation. Additionally, after ultrasonic assisted surface modification, separation of PVC and PET with different mass ratios was obtained efficiently through one-stage flotation. The purity and the recovery of the obtained products after flotation separation are up to 99.30% and 99.73%, respectively. A flotation process was designed for flotation separation of PVC and PET plastics combined with surface modification. This study provides technical insights into physical separation of plastic wastes for recycling industry.
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Chongqing
authors.initials: C
authors.lastname: Wang
authors.affiliation: School of Chemistry and Chemical Engineering, 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, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Jiangang
authors.initials: J
authors.lastname: Fu
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Chengcheng
authors.initials: C
authors.lastname: Luo
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha, 410083 Hunan, China.
authors.forename: Younian
authors.initials: Y
authors.lastname: Liu
mesh_terms: D011093:Polyethylene Terephthalates / Q000737:chemistry*; D011143:Polyvinyl Chloride / Q000737:chemistry*; D011196:Potassium Permanganate / Q000737:chemistry*; D059027:Recycling / Q000379:methods*; D012037:Refuse Disposal / Q000379:methods; D062611:Solid Waste / Q000032:analysis*; D018505:Waste Management / Q000379:methods*
chemical_list: D011093:Polyethylene Terephthalates; D062611:Solid Waste; D011196:Potassium Permanganate; D011143:Polyvinyl Chloride
keywords: Flotation; Plastics recycling; Polyvinyl chloride; Surface modification