Separation of polyethylene terephthalate from municipal waste plastics by froth flotation for recycling industry

Journal Article · Thu Jan 15 04:00:00 EST 2015 · Waste Management

DOI:https://doi.org/10.1016/J.WASMAN.2014.09.025· OSTI ID:22443599

Wang, Chong-Qing; Wang, Hui; Liu, You-Nian

Highlights: • Factors of NaOH treatment were studied by orthogonal and single factor experiments. • Mechanism of alkaline treatment for facilitating flotation was manifested. • Flotation separation of PET was achieved with high purity and efficiency. • A flow sheet of purification PET from MWP was designed. - Abstract: Recycling is an effective way to manage plastic wastes and receives considerable attention. Since plastic mixtures are difficult to recycle because of their intrinsic characteristics, separation of mixed plastics is the key problem for recycling. Separation of polyethylene terephthalate (PET) from municipal waste plastics (MWP) by froth flotation combined with alkaline pretreatment was investigated for recycling industry. The effect of process variables was estimated by L{sub 9} (3{sup 4}) orthogonal array of experiments and single factor experiments. The optimum conditions of alkaline pretreatment are 10 wt% sodium hydroxide, 20 min and 70 °C. After alkaline pretreatment under optimum conditions, flotation separation PET from acrylonitrile–butadiene–styrene, polystyrene, polycarbonate or polyvinyl chloride was achieved with high purity and efficiency. The purity of PET is up to 98.46% and the recovery is above 92.47%. A flow sheet of separation PET from MWP by a combination of froth flotation and sink float separation was designed. This study facilitates industrial application of plastics flotation and provides technical insights into recycling of waste plastics.

• OSTI ID: 22443599
• Journal Information: Waste Management, Journal Name: Waste Management Vol. 35; ISSN WAMAE2; ISSN 0956-053X
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
ACRYLONITRILE
FLOTATION
INDUSTRY
MATERIALS RECOVERY
MUNICIPAL WASTES
POLYCARBONATES
POLYESTERS
POLYSTYRENE
PURIFICATION
PVC
RECYCLING
SEPARATION PROCESSES
SODIUM HYDROXIDES
STYRENE