Kinetics of hydrolysis of poly(ethylene terephthalate) powder in sulfuric acid by a modified shrinking-core model

Citation
T. Yoshioka et al., Kinetics of hydrolysis of poly(ethylene terephthalate) powder in sulfuric acid by a modified shrinking-core model, IND ENG RES, 40(1), 2001, pp. 75-79
Citations number
9
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemical Engineering
Journal title
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
ISSN journal
0888-5885 → ACNP
Volume
40
Issue
1
Year of publication
2001
Pages
75 - 79
Database
ISI
SICI code
0888-5885(20010110)40:1<75:KOHOPT>2.0.ZU;2-4
Abstract
Poly(ethylene terephthalate) (PET) powder from waste bottles was degradated at atmospheric pressure in 3-9 M sulfuric acid below 150-190 degreesC for 12 h to clarify the mechanism for a feedstock recycle process. Terephthalic acid (TPA) and ethylene glycol (EG) were produced by the acid-catalyzed he terogeneous hydrolysis of PET in sulfuric acid. The TPA yield agreed with t he degree of hydrolysis of PET, but the EG yield decreased with increasing sulfuric acid concentration because of carbonization of EG. The kinetics of hydrolysis of PET in sulfuric acid could be explained by a modified shrink ing-core model for the chemical reaction control, in which the effective su rface area is proportional to the degree of hydrolyzed PET, x, affected by formation and growth of pore and crack on PET powder. The apparent rate con stant was proportional to the reciprocal of the particle size and the activ ity of sulfuric acid, and the activation energy was 88.7 kJ/mol.