Scheint verschiedene Patente dafür zu geben:
Bibliographic Information
Process for the production of 1,4-butanediol, gamma-butyrolactone and tetrahydrofuran. Tuck, Michael William Marshall; Wood, Michael Anthony; Hiles, Andrew George. (Kvaerner Process Technology Limited, UK; Tuck, Michael William Marshall; Wood, Michael Anthony; Hiles, Andrew George). PCT Int. Appl. (1997), 27 pp. CODEN: PIXXD2 WO 9743242 A1 19971120[...]
Abstract
The prodn. of ³1 C4 compd. selected from 1,4-butanediol, g-butyrolactone, and THF, which includes the vapor-phase hydrogenation of a di-(C1-4 alkyl) maleate in the presence of a particulate ester hydrogenation catalyst, comprises: (a) contacting a vapor stream contg. maleic anhydride vapor, water vapor, and carbon oxides in an absorption zone with a high-boiling org. solvent having a b.p. at atm. pressure which is ³30° higher than that of the di-(C4-4 alkyl) maleate so as to form a soln. of maleic anhydride in the high-boiling org. solvent; (b) recovering from the absorption zone a waste gas stream; (c) reacting maleic anhydride in the soln. of the maleic anhydride of step (a) under esterification conditions in an esterification zone with a C1-4 alkanol to form the corresponding di-(C1-4 alkyl) maleate; (d) recovering from the esterification zone a soln. of the di-(C1-4 alkyl) maleate in the high-boiling solvent; (e) contacting the soln. of the di-(C1-4 alkyl) maleate in the high-boiling solvent with a gaseous stream contg. hydrogen to strip the di-(C1-4 alkyl) maleate therefrom and to form a vaporous stream comprising hydrogen and the maleate diester. Next, (f) one contacts the material of the vaporous stream of step (e) in a hydrogenation zone under ester hydrogenation conditions in the presence of a heterogeneous ester hydrogenation catalyst to convert the maleate diester to at ³1 C4 compd. selected from 1,4-butanediol, g-butyrolactone, and tetrahydrofuran; and (g) recovers from the hydrogenation zone a product stream. A process flow diagram is presented.
Patent Classifications
Main IPC: C07C067-08. Secondary IPC: C07C069-60; C07C029-149; C07C029-17; C07C033-035; C07D307-33; C07D307-08.
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Bibliographic Information
Process for production of g-butyrolactone and tetrahydrofuran by hydrogenation of maleic anhydride recovered from vapor-phase oxidation of n-butane. Bertola, Aldo; Constantinescu, Take; Raucq, Philippe; Cassarino, Salvatore. (Pantochim S.A., Belg.). PCT Int. Appl. (2000), 28 pp. CODEN: PIXXD2 WO 2000027834 A1 20000518 [...]
Abstract
The process consists essentially of the following steps: (A) converting n-butane to maleic anhydride (I) by catalytic vapor-phase oxidn.; (B) recovering I from the effluent gases of butane oxidn. by selective absorption in g-butyrolactone (II), forming a I-II mixt.; (C) removing water from the mixt. in a stripper under the action of a gas and/or under vacuum conditions, producing a I-II mixt. with min. water and maleic acid content; (D) recovering II contained in the exhaust gases leaving the I absorber, by absorption in water; (E) dehydrating the recovered II and recycling it to the I absorber; (F) hydrogenating the dewatered I-II mixt. over suitable catalysts under conditions favoring the formation of THF and II; (G) sepg. by distn. THF, II and the byproducts from the resulting hydrogenation mixt.; (H) recycling a II-rich stream to the selective absorption of I.
Patent Classifications
Main IPC: C07D307-08. Secondary IPC: C07D307-33.
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