-
公开(公告)号：DE3642410A1
公开(公告)日：1987-10-01
申请号：DE3642410
申请日：1986-12-11
Applicant: UNION CARBIDE CORP
Abstract: A process is provided for the utilization of dialkyl carbonates formed as by-products in a continuous process for the synthesis of oxalic acid esters from nitrous acid esters and carbon monoxide and wherein the esters are subsequently used as intermediates in the production of commercially useful products, such as ethylene glycol. The process comprises contacting a mixture containing the by-product comprised of a dialkyl carbonate with an aqueous solution of a metal carbonate under hydrolyzing conditions whereby the dialkyl carbonate is converted to the corresponding alkanol and the metal carbonate is converted to metal bicarbonate. Upon distillation of the alkanol from the mixture the bicarbonate is converted back to the metal carbonate which can then be recycled from the bottoms to the hydrolyzing zone for use in further hydrolysis of by-product. The alkanol is recycled for use in the continuous process.
-
公开(公告)号：ZA8609304B
公开(公告)日：1987-07-29
申请号：ZA8609304
申请日：1986-12-09
Applicant: UNION CARBIDE CORP
IPC: C07C69/36 , C07C29/09 , C07C29/147 , C07C31/04 , C07C67/36 , C07C67/48 , C07C67/60 , C07C69/96 , C01B , C07B , C07C
CPC classification number: C07C29/095 , C07C31/04
-
公开(公告)号：CA1336720C
公开(公告)日：1995-08-15
申请号：CA578727
申请日：1988-09-28
Applicant: UNION CARBIDE CORP
Inventor： CRANDALL JOHN WORTH , REAM BERNARD CLAUDE
IPC: C07C27/00 , C07C29/149 , C07C29/80 , C07C31/20 , C07C67/00
Abstract: A process is described for recovering polyester-grade ethylene glycol from crude ethylene glycol containing at least one component which has a normal boiling point below that of ethylene glycol, and which can form a UV absorber in the presence of ethylene glycol which comprises supplying to an ethylene glycol distillation system, preferably comprising a fractional distillation zone having an upper portion, a lower portion and an intermediate portion a crude ethylene glycol stream at a determined pH of less than about 7.5; maintaining within the intermediate portion of the fractional distillation zone a diluent having a boiling point below that of the at least one component, such as methanol, at a concentration sufficient to reduce the formation of UV absorber in the intermediate portion wherein at least ethylene glycol, the at least one component and the diluent, are present, and withdrawing ethylene glycol substantially free of the at least one component from the lower portion of the fractional distillation zone.
-
公开(公告)号：DE3270350D1
公开(公告)日：1986-05-15
申请号：DE3270350
申请日：1982-02-19
Applicant: UNION CARBIDE CORP
Inventor： GIBSON CHARLES ARNOLD , CRANDALL JOHN WORTH
IPC: C07C211/10 , C07C67/00 , C07C209/00 , C07C209/84 , C07C211/14 , C07C85/26 , C07C87/16 , C07C87/20
-
公开(公告)号：DE3851400D1
公开(公告)日：1994-10-13
申请号：DE3851400
申请日：1988-09-28
Applicant: UNION CARBIDE CORP
Inventor： CRANDALL JOHN WORTH , REAM BERNARD CLAUDE
IPC: C07C27/00 , C07C29/149 , C07C29/80 , C07C31/20 , C07C67/00
Abstract: A process is described for recovering polyester-grade ethylene glycol from crude ethylene glycol containing at least one component which has a normal boiling point below that of ethylene glycol, and which can form a UV absorber in the presence of ethylene glycol which comprises supplying to an ethylene glycol distillation system, preferably comprising a fractional distillation zone having an upper portion, a lower portion and an intermediate portion a crude ethylene glycol stream at a determined pH of less than about 7.5; maintaining within the intermediate portion of the fractional distillation zone a diluent having a boiling point below that of the at least one component, such as methanol, at a concentration sufficient to reduce the formation of UV absorber in the intermediate portion wherein at least ethylene glycol, the at least one component and the diluent, are present, and withdrawing ethylene glycol substantially free of the at least one component from the lower portion of the fractional distillation zone.
-
Patent Agency Ranking
公开(公告)号：GB2188315B
公开(公告)日：1989-12-28
申请号：GB8629583
申请日：1986-12-10
Applicant: UNION CARBIDE CORP
Abstract: A process is provided for the utilization of dialkyl carbonates formed as by-products in a continuous process for the synthesis of oxalic acid esters from nitrous acid esters and carbon monoxide and wherein the esters are subsequently used as intermediates in the production of commercially useful products, such as ethylene glycol. The process comprises contacting a mixture containing the by-product comprised of a dialkyl carbonate with an aqueous solution of a metal carbonate under hydrolyzing conditions whereby the dialkyl carbonate is converted to the corresponding alkanol and the metal carbonate is converted to metal bicarbonate. Upon distillation of the alkanol from the mixture the bicarbonate is converted back to the metal carbonate which can then be recycled from the bottoms to the hydrolyzing zone for use in further hydrolysis of by-product. The alkanol is recycled for use in the continuous process.
-
公开(公告)号：GB2188315A
公开(公告)日：1987-09-30
申请号：GB8629583
申请日：1986-12-10
Applicant: UNION CARBIDE CORP
Abstract: A process is provided for the utilization of dialkyl carbonates formed as by-products in a continuous process for the synthesis of oxalic acid esters from nitrous acid esters and carbon monoxide and wherein the esters are subsequently used as intermediates in the production of commercially useful products, such as ethylene glycol. The process comprises contacting a mixture containing the by-product comprised of a dialkyl carbonate with an aqueous solution of a metal carbonate under hydrolyzing conditions whereby the dialkyl carbonate is converted to the corresponding alkanol and the metal carbonate is converted to metal bicarbonate. Upon distillation of the alkanol from the mixture the bicarbonate is converted back to the metal carbonate which can then be recycled from the bottoms to the hydrolyzing zone for use in further hydrolysis of by-product. The alkanol is recycled for use in the continuous process.
-
公开(公告)号：ZA887281B
公开(公告)日：1989-06-28
申请号：ZA887281
申请日：1988-09-28
Applicant: UNION CARBIDE CORP
Inventor： CRANDALL JOHN WORTH , JOHN WORTH CRANDALL , REAM BERNARD CLAUDE , BERNARD CLAUDE REAM
Abstract: A process is described for recovering polyester-grade ethylene glycol from crude ethylene glycol containing at least one component which has a normal boiling point below that of ethylene glycol, and which can form a UV absorber in the presence of ethylene glycol which comprises supplying to an ethylene glycol distillation system, preferably comprising a fractional distillation zone having an upper portion, a lower portion and an intermediate portion a crude ethylene glycol stream at a determined pH of less than about 7.5; maintaining within the intermediate portion of the fractional distillation zone a diluent having a boiling point below that of the at least one component, such as methanol, at a concentration sufficient to reduce the formation of UV absorber in the intermediate portion wherein at least ethylene glycol, the at least one component and the diluent, are present, and withdrawing ethylene glycol substantially free of the at least one component from the lower portion of the fractional distillation zone.
-
公开(公告)号：DE2855258A1
公开(公告)日：1979-06-28
申请号：DE2855258
申请日：1978-12-21
Applicant: UNION CARBIDE CORP
Inventor： HIGLEY DAVID PAGE , CULP GARY LYNN , CRANDALL JOHN WORTH , FARQUHAR SCOTT MARK
IPC: C07D317/36 , B01D1/00 , B01D1/06 , B01D3/14 , C07C45/00 , C07C45/50 , C07C45/82 , C07C67/00 , C07D317/38 , B01D3/00 , B01D1/22 , B01D1/30
Abstract: This invention is concerned with a continuous process for separating higher boiling, heat sensitive components from a liquid product stream. It involves a rapid evaporation of the desired product of the stream in an evaporator which minimizes residence time, such as a falling film evaporator, and feeding the vapors and the remainder of the stream to a separation column where the vaporized products rise in the column. Part of the vaporized products are removed after condensation and then recycled back to the column as a reflux. This reflux after contacting one or more trays is collected and recycled to the evaporator and mixed with the product feed being treated. The liquid remainder of the feed stream is collected at the bottom of the column. The bottom of the column can be kept at a temperature which minimizes any breakdown of the heat sensitive components present therein and, if desired, the bottoms in the column can be quickly withdrawn for treatment elsewhere or for recycling back to the process. A desirable embodiment is to recycle a portion of the residue at the bottom of the column back to the evaporator.
-
公开(公告)号：DE3851400T2
公开(公告)日：1995-01-19
申请号：DE3851400
申请日：1988-09-28
Applicant: UNION CARBIDE CORP
Inventor： CRANDALL JOHN WORTH , REAM BERNARD CLAUDE
IPC: C07C27/00 , C07C29/149 , C07C29/80 , C07C31/20 , C07C67/00
Abstract: A process is described for recovering polyester-grade ethylene glycol from crude ethylene glycol containing at least one component which has a normal boiling point below that of ethylene glycol, and which can form a UV absorber in the presence of ethylene glycol which comprises supplying to an ethylene glycol distillation system, preferably comprising a fractional distillation zone having an upper portion, a lower portion and an intermediate portion a crude ethylene glycol stream at a determined pH of less than about 7.5; maintaining within the intermediate portion of the fractional distillation zone a diluent having a boiling point below that of the at least one component, such as methanol, at a concentration sufficient to reduce the formation of UV absorber in the intermediate portion wherein at least ethylene glycol, the at least one component and the diluent, are present, and withdrawing ethylene glycol substantially free of the at least one component from the lower portion of the fractional distillation zone.
-
-
-
-
-
-
-
-
-
Search Results
12
records
(took 0.024 seconds)
