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5568339 
Journal Article 
Deplasticization and dechlorination of flexible polyvinyl chloride in NaOH solution by microwave heating 
Osada, F; Yana, J 
2010 
Yes 
Journal of Material Cycles and Waste Management
ISSN: 1438-4957
EISSN: 1611-8227 
SPRINGER 
NEW YORK 
12 
3 
245-253 
English 
WOS:000283122400008 
This study investigated the deplasticization and dechlorination of flexible polyvinyl chloride (PVC) containing 59.2% PVC, 29.7% dioctyl phthalate (DOP), and approximately 12% stabilizers. Flexible PVC was treated with NaOH solutions at concentrations in the range 2-16 mol/l and heated by microwaves to temperatures between 100 degree and 250 degree C for 0-120 min. DOP was extracted from flexible PVC into the NaOH solution as a phthalic acid salt; the remaining PVC was subsequently dechlorinated by increasing the temperature. On internal heating using microwaves, the plasticizer was 100% extracted during processing at 150 degree C for 30 min, whereas the chlorides were 100% removed during processing at 235 degree C for 30 min; the residue was converted into hydrocarbon compounds. The maximum weight loss ratio was 71% compared to the pretreatment state. It was also found that 100% deplasticization and dechlorination was possible using 8 mol/l NaOH solution, which is almost half the concentration employed when using conventional external heating systems. 
Flexible PVC; Flexible PVC waste; High-temperature alkaline solution treatment; Phthalic acid; Microwave heating