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过程工程学报 2001
MethanolsisofPoly(ethyleneterephthalate)inSupercriticalPhaseKeywords: polyethyleneterephthalate(PET),methanolysis,chemicalrecycling,supercriticalfluid,depolymerization Abstract: Thedepolymerizationofpoly(ethyleneterephthalate,PET)insupercriticalmethanolisstudiedusingastainlessstirredautoclaveattemperatureof255~260℃,pressureof8.5~14.0MPa,andmethanol/PETweightratioof3~8.Undertheoptimalconditions,thePETisdepolymerizedcompletelytoitsmonomersin60min.Themainproductsofthereactionaredimethylterephthalateandethyleneglycol.Therearestillsomesmallamountsofbyproducts,suchasmethyl？(2-hydroxyethyl)terephthalate,bis(hydroxyethyl)terephthalate,dimersandoligomers.Reversed-phasehighperformanceliquidchrom-atographyandgaschromatographyareusedtoanalyzesolidproductsandliquidproductsrespectively.TheresultsofdepolymerizationshowthattheyieldofdimethylterephthalateandthedegreeofPETdepolymerizationaredependentonthereactiontemperature,weightratioofmethanoltoPETandreactiontime.Butthereactionpressurehaslittleinfluenceonthedepolymerizationaslongasmethanolisinsupercriticalstate.
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