초록 ▼

The present invention relates to a method of recovering terephthalic acid from a material containing poly(ethylene terephthalate) (P.E.T.) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the te

The present invention relates to a method of recovering terephthalic acid from a material containing poly(ethylene terephthalate) (P.E.T.) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the terephthalic acid, until a water-soluble compound is obtained, and subsequently carrying out dissolution in water and acidification.

대표청구항 ▼

The present invention relates to a method of recovering terephthalic acid from a material containing poly(ethylene terephthalate) (P.E.T.) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the te

The present invention relates to a method of recovering terephthalic acid from a material containing poly(ethylene terephthalate) (P.E.T.) in the form of bottles, by making said material react, in the absence of water, with a reagent consisting of one or more metal salts of a weaker acid than the terephthalic acid, until a water-soluble compound is obtained, and subsequently carrying out dissolution in water and acidification. l, pyrimidinyl, pyridazinyl, indolyl, isoindolyl, triazinyl, tetrahydrofuranyl, pyrazolidinyl, pyrrolidinyl, pyrrolinyl, imidazolinydinyl, piperidinyl, pyranyl, thiopyranyl, piperazinyl, morpholinyl or thiomorpholinyl. 12. A process according to claim 1, wherein R2is an unsubstituted or halo gen-, methoxy-, ethoxy-, propyloxy-, isopropyloxy-, n-butyloxy-, isobutyloxy-, sec-butyloxy- or tert-butyloxy-, methyl-, ethyl-, n-propyl-, isopropyl-, n-butyl-, sec-butyl-, isobutyl-, tert-butyl-, n-amyl-, tert-amyl-, 1-hexyl- or 3-hexyl-substituted C1-C6alkyl, C3-C6cycloalkyl, C3-C6cycloalkyl-C1-C2alkyl, aryl, aryl-C1-C2alkyl, heterocyclyl or heterocyclyl-C1-C2alkyl. 13. A process according to claim 12, wherein the heterocyclyl is an aromatic and non-aromatic heterocylcyl moiety with 3 to 8 ring members of which at least one is a nitrogen, oxygen or sulfur. 14. A process according to claim 13, wherein the heterocyclyl is furyl, benzofuranyl, thienyl, benzothienyl, pyrrolyl, imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolyl, isoindolyl, triazinyl, tetrahydrofuranyl, pyrazolidinyl, pyrrolidinyl, pyrrolinyl, imidazolinydinyl, piperidinyl, pyranyl, thiopyranyl, piperazinyl, morpholinyl or thiomorpholinyl. 15. A process according to claim 1, wherein the step of diazotizing the aniline of formulae is performed with a compound selected from the group consisting of isoamyl nitrite, phenyl nitrite, nitrous acid, sodium nitrite, potassium nitrite, and magnesium nitrite. 16. A process for the preparation of a compound of formula I wherein: R1is an unsubstituted or halogen-, phenoxy-, methoxy-, ethoxy-, propyloxy-, isopropyloxy-, n-butyloxy-, isobutyloxy-, sec-butyloxy- or tert-butyloxy-substituted methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-amyl, tert-amyl, 1-hexyl or 3-hexyl; and R2is an unsubstituted or halogen-, methoxy-, ethoxy-, propyloxy-, isopropyloxy-, n-butyloxy-, isobutyloxy-, sec-butyloxy- or tert-butyloxy-, methyl-, ethyl-, n-propyl-, isopropyl-, n-butyl-, sec-butyl-, isobutyl-, tert-butyl-, n-amyl-, tert-amyl-, 1-hexyl- or 3-hexyl-substituted C1-C6alkyl, C3-C6cycloalkyl, C3-C6cycloalkyl-C1-C2alkyl, aryl, aryl-C1-C2alkyl, heterocyclyl or heterocyclyl-C1-C2alkyl; wherein the heterocyclyl is an aromatic and non-aromatic heterocylcyl moiety with 3 to 8 ring members of which at least one is a nitrogen, oxygen or sulfur; comprising the steps of: (1) diazotizing an aniline of formula II with a compound selected from organic nitrites, inorganic nitrites and nitrous acid to obtain a diazonium salt; (2) preparing an oxime of formula III by reacting hydroxylamine or a salt of hydroxylamine with a glyoxylic acid ester of formula IIIA or an hemiacetal of formula IIIB (3) reacting the diazonium salt with the oxime in presence of a copper(II)-salt.