Decomposition of polycarbonate in subcritical and supercritical water

Tagaya, Hideyuki; Katoh, Kazuya; Kadokawa, Jun‐ichi; Chiba, Koji

doi:10.1016/s0141-3910(98)00204-3

Cited by 100 publications

(77 citation statements)

References 9 publications

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“…The latter temperature has been selected as a maximum, because it is known that BPA, obtained by hydrolysis of PC, starting from 300°C decomposes giving place to phenol (Tagaya et al, 1999). Fig.…”

Section: Resultsmentioning

confidence: 99%

“…These processes can require a complicate product separation in addition with environmental safety problems related to the use of more or less toxic organic solvents. Also decomposition of PC in suband super-critical water has been taken into account by Tagaya et al (1999).…”

Section: Physical Propertiesmentioning

confidence: 99%

“…Pyrolysis of PC in subcritical and supercritical water was studied by Tagaya et al (1999). Water has the advantage to be in-expensive and non-toxic.…”

Section: Ester Exchange Reaction and Hydrolysis Of Poly(bisphenol A Cmentioning

confidence: 99%

“…In these conditions the decomposition reaction is more selective and the products are reduced to phenol, bisphenol A, p-isopropenylphenol and p-isopropylphenol. Tagaya et al (1999) decomposed PC in the temperature range from 230°C to 430°C. No decomposition occurred below 230°C even for a reaction time of 24 h. Production of phenol, BPA, p-isopropenylphenol and p-isopropylphenol begin starting from 240°C.…”

Section: Ester Exchange Reaction and Hydrolysis Of Poly(bisphenol A Cmentioning

confidence: 99%

“…In order to extend the results obtained by Tagaya et al (1999), several experiments have been performed by adopting liquid water in the more convenient subcritical conditions. The results obtained in decomposing PC and producing BPA, will be reported in the following.…”

Section: Hydrolysis Near the Critical Pointmentioning

confidence: 99%

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Poly(bisphenol A carbonate) Recycling: High Pressure Hydrolysis Can Be a Convenient Way

Bozzano¹,

Dente²,

Rosso³

2012

Material Recycling - Trends and Perspectives

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Section: Resultsmentioning

confidence: 99%

Section: Physical Propertiesmentioning

confidence: 99%

“…Pyrolysis of PC in subcritical and supercritical water was studied by Tagaya et al (1999). Water has the advantage to be in-expensive and non-toxic.…”

Section: Ester Exchange Reaction and Hydrolysis Of Poly(bisphenol A Cmentioning

confidence: 99%

Section: Ester Exchange Reaction and Hydrolysis Of Poly(bisphenol A Cmentioning

confidence: 99%

Section: Hydrolysis Near the Critical Pointmentioning

confidence: 99%

See 3 more Smart Citations

Poly(bisphenol A carbonate) Recycling: High Pressure Hydrolysis Can Be a Convenient Way

Bozzano¹,

Dente²,

Rosso³

2012

Material Recycling - Trends and Perspectives

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Characteristics and kinetics of degradation of polystyrene in supercritical water

Kwak

Shin

Bae

et al. 2006

J of Applied Polymer Sci

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ABSTRACT:The degradation of polystyrene (PS) in subor supercritical water was carried out at reaction temperatures ranging from 370°C to 420°C and pressures of 240 to 320 bar. At 370°C, where water is in a subcritical state, the degradation was in equilibrium in about 5 min, whereas at 380°C and 390°C, where water is in a supercritical state, it was completed in 15 and 3 min, respectively. The equilibrium conversion in the supercritical state (100 wt %) was higher than that in the subcritical water (ca. 80 wt %). The dependence on time of selectivity for the degradation products-styrene monomer, styrene dimer, styrene trimer, toluene, ethyl benzene, isopropyl benzene, and triphenyl benzene-were investigated at 400°C and 280 bar. As the reaction proceeded, selectivity for styrene monomers, dimers, and trimers decreased, whereas that for toluene, ethyl benzene, and isopropyl benzene increased because of the difficulty of decomposing the benzene rings and phenyl radicals. Triphenyl benzene increased with reaction time for the same reason. With increasing temperature, selectivity for the styrene monomers and dimers decreased slightly, whereas selectivity for toluene and ethyl benzene increased a little. The kinetic behavior of PS in supercritical water along with supercritical acetone and n-hexane were investigated. The degradation processes of PS in such supercritical fluids could be formulated by the first-order kinetic law at the initial stage of the reaction. The activation energy for the degradation in supercritical water was evaluated to be 157 kJ/mol compared to an activation energy of 132 kJ/mol in the supercritical n-hexane.

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Thermal decomposition of polystyrene in supercritical methanol

Shin

Bae

2008

J of Applied Polymer Sci

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The degradation of polystyrene (PS) in supercritical methanol was carried out under reaction temperatures ranging from 340 to 4208C and pressures of 10-30 MPa. The selectivity of liquid products was investigated at various reaction conditions. As the reaction proceeded, the selectivity of styrene monomer, dimer, 1,3-diphenyl propane, and 1,3-diphenyl butane had a declining tendency, whereas that of the rest (i.e., toluene, ethyl benzene, isopropyl benzene, and 3-phenyl propanol, etc.) had an inclining tendency. The sequences of decomposition reaction could be reasoned by analyzing the variation of selectivity of liquid products. The kinetic behavior of PS in supercritical methanol had been investigated. The degradation processes of PS in such supercritical fluids could be formulated by the firstorder kinetic law at the initial stage of reaction. The activation energy for the degradation in supercritical methanol was evaluated to be 117.2 kJ/mol and it was also compared with the activation energies for depolymerization in other supercritical fluids and that for thermal pyrolysis.

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Decomposition of polycarbonate in subcritical and supercritical water

Cited by 100 publications

References 9 publications

Poly(bisphenol A carbonate) Recycling: High Pressure Hydrolysis Can Be a Convenient Way

Poly(bisphenol A carbonate) Recycling: High Pressure Hydrolysis Can Be a Convenient Way

Characteristics and kinetics of degradation of polystyrene in supercritical water

Thermal decomposition of polystyrene in supercritical methanol

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