EP0000110A1 - Verfahren zur Herstellung von Acrylsäure aus deren Lösungen in Tri-n-butylphosphat - Google Patents
Verfahren zur Herstellung von Acrylsäure aus deren Lösungen in Tri-n-butylphosphat Download PDFInfo
- Publication number
- EP0000110A1 EP0000110A1 EP78400011A EP78400011A EP0000110A1 EP 0000110 A1 EP0000110 A1 EP 0000110A1 EP 78400011 A EP78400011 A EP 78400011A EP 78400011 A EP78400011 A EP 78400011A EP 0000110 A1 EP0000110 A1 EP 0000110A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- acrylic acid
- tri
- butyl phosphate
- column
- distillation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
- C07C51/44—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation by distillation
Definitions
- the subject of the present invention is a process for the separation of acrylic acid from its solutions in tri-n-butyl phosphate, by a particular distillation technique.
- tri-n-butyl phosphate is particularly effective.
- the separation of acrylic acid from its solutions in this solvent encounters many difficulties.
- tributyl phosphate degrades when it is subjected to high temperatures; especially in the presence of acids and / or water, so that the depletion of acrylic acid in the solution, by distillation at normal pressure or under a slightly reduced pressure results in a significant loss of solvent.
- to obtain a good absorption or extraction yield of acrylic acid using the tributyl phosphate recycled after distillation it is necessary that the latter have as low an acid titer as possible. acrylic.
- the starting solution can be of any origin. It can result, for example, from the absorption of acrylic acid by tri-n-butyl phosphate from the gas mixture obtained by oxidation of propylene and / or acrolein, as described in French patent 1 558 432 already cited. It can also be obtained from the liquid-liquid extraction of aqueous solutions of acrylic acid with tri-n-butyl phosphate. It can also contain without disadvantage small quantities of other organic acids lighter than acrylic acid, in particular acetic acid, formed (s) at the same time as acrylic acid and driven (s) by the solvent . As we will see later, these acids can easily be isolated in a complementary stage, within the framework of the process of the invention.
- the concentration of acrylic acid in the starting solution is indifferent, the process of the invention applying as well and being as interesting in the case of concentrated or diluted solutions of acrylic acid.
- the initial solution may contain from 5 to 50% by weight of acrylic acid.
- a vapor phase is formed comprising substantially all of the acrylic acid and part of the tri-n-butyl phosphate, by heating the initial liquid under conditions which avoid degradation of the tributyl phosphate.
- the upper temperature limit is an essential factor. Noticeably not to exceed 160 ° C, the most advantageous temperature range being between 110 "C and 150 ° C.
- the duration of the heating is also of some importance and must be controlled; the residence times are as shorter as the temperature adopted is higher; for the aforementioned temperature range, residence times of between approximately 30 minutes and 5 seconds are generally suitable for obtaining a vapor phase containing, according to the invention, almost -all of the acrylic acid and a fraction of the tributyl phosphate without degradation of the solvent in the liquid or vapor phase.
- the pressure to be applied is deduced from the other operating conditions; its determination is therefore within the reach of those skilled in the art.
- the liquid remaining after this vaporization phase consists of tri-n-butyl phosphate substantially free from acrylic acid and from any other light organic acid which may have been present in the starting liquid.
- Obtaining tri-n-butyl phosphate depleted of organic acid, after this first operating stage, represents one of the important advantages of the process according to the invention. Indeed, thanks to this rapid recovery of a large fraction of the solvent, it is subjected for a minimum period to a thermal effect and the best conditions are met to avoid degradation of the phosphate; Moreover; as the solvent recovered is not charged with acid, it can be recycled directly to the operations of extraction or absorption of acrylic acid from solutions or gases containing it, where it gives its maximum extraction yield or absorption.
- the vapor phase formed in the first stage is subjected to a distillation making it possible to collect acrylic acid of high purity.
- the temperature conditions of this distillation are critical: in fact, the boiling point of the liquid must not exceed the temperature at which the tributyl phosphate degrades appreciably, i.e. around 160 ° C, the range most advantageous working temperature between 120 and 150 ° C. This result cannot be achieved in a conventional manner by a sufficient reduction in pressure since acrylic acid crystallizes in the overhead condenser when the pressure prevailing in the column is lowered to one. value less than 5 mm Hg.
- an amount of acrylic acid is maintained at the bottom of the column at least sufficient to be able to carry out the distillation under the desired temperature conditions.
- the amount of acrylic acid to be maintained in the solution can be between 1 and 20%, "preferably 2 to 10% for the preferred temperature range mentioned above.
- the residence tempo assumes a certain importance; it is also the shorter the higher the temperature for a temperature of 120 ° to 150 "C, it is between 1 hour and 30 seconds.
- the pressure is adjusted according to the temperature and the acrylic acid content chosen in each particular case and its determination is within the reach of those skilled in the art. A pressure range between 5 and 30 mm Hg is generally suitable for all cases.
- the liquid leaving the bottom of the column composed of tri-n-butyl phosphate and a certain amount of acrylic acid, is advantageously recycled to the vaporization stage which constitutes the first stage of the process according to the present invention. It is easy to see the advantage of this recycling, which makes it possible to collect, over the whole process, all of the acrylic acid and tri-n-butyl phosphate contained in the starting solution.
- An embodiment of the process can moreover constitute regulating the operation of the distillation column so that the liquid leaving the bottom of the column and recycled at the first stage has a concentration of the same order as that of the solution. of departure. However, this mode of implementation is not imperative and it is perfectly possible to work with initial and recycling solutions having different concentrations.
- the method according to the present invention may include a number of variants which can be applied separately or simultaneously.
- the starting solution contains, alongside acrylic acid, other light organic acids, in particular acetic acid
- acetic acid one proceeds in a complementary stage, to the distillation of this acid.
- This separation takes place prior to the distillation of acrylic acid.
- the conditions of temperature and pressure are to be compared to those of the distillation of acrylic acid, that is to say that it is necessary to apply a temperature at the bottom of the column which does not cause the degradation of the phosphate. of tributyl and not to lower the pressure to such an extent that freezing of acetic acid results.
- a temperature of the order of 120-150 ° C and a pressure of 30 to 100 mm of mercury are favorable working conditions.
- a second variant which is particularly advantageous when the method is applied to solutions that are relatively concentrated in acrylic acid
- all or part of the solution to be treated is introduced, downstream of the vaporization device, preferably in the distillation column itself. , at a level where the acrylic acid concentration is substantially identical to that of the feed solution. Part of the acrylic acid distills and the liquid remaining in the bottom of the column is sent to the vaporization device. In other words, the entire operating cycle remains otherwise unchanged.
- the vaporization device for example a thin film evaporator, is supplied with solution to be treated via line 2.
- the tri-n-butyl phosphate freed from acrylic acid and any other acid any is withdrawn and sent via line 3 at the absorption or extraction stage of acrylic acid, upstream of the process. according to the invention.
- the vapor phase containing acrylic acid, possibly light acids such as acetic acid and a certain amount of tri-n-butyl phosphate leaves the device 1 via line 4, then after partial or total condensation, is introduced. in column 5 where the acetic acid passes overhead and is collected by the pipe 6.
- the remaining liquid phase flows through line 7 and feeds the distillation column 8 where the acrylic acid escapes through 9 while the liquid withdrawn at the foot of the column is recycled via line 10 to the supply of the device 1.
- the column 5 is optional and is eliminated if the supply solution does not contain acids other than acrylic acid.
- the process according to the present invention can be carried out continuously or batchwise.
- the thin-film evaporator (1) is supplied via the tubing (2) with 108.78 parts by weight of a mixture containing 6.52% by weight of acrylic acid 93.30% of tributylphosphate, 0.01% of and 0.17% acetic acid.
- 82.66 parts of this mixture come from an acrylic acid absorption system by tri-n-butyl phosphate and 26.12 parts from a recycling by this line 10.
- the evaporator (1) is maintained, by means of an appropriate system, under a pressure of 5 mm of mercury and at a temperature of 128 ° C. A separation takes place into a liquid fraction and a vapor fraction.
- the liquid fraction drawn off by (3), at the bottom of the apparatus, represents 76.77 parts containing 0.1% by weight of acrylic acid and 99.9% of tributylphosphate. This liquid, after proper cooling is returned to the acrylic acid extractor.
- the steam fraction, leaving in (4), after partial or total condensation is sent to the distillation column (5). It represents 32.01 parts by weight containing 21.90% by weight of acrylic acid, 77.46% of tributylphosphate, 0.59% of acetic acid and 0.03% of water.
- This product is sent to column (8) operating under 10 mm of mercury at the top and 12 mm at the bottom.
- the temperatures are 40 and 130 ° C respectively.
- the overhead fraction (9) of 5.7 parts by weight corresponds to the production of acrylic acid at a purity of 99.65%.
- the effluent flowing by 10 composed of 26.12 parts of a liquid containing 94.95% of tributyl phosphate and 5.05% of acrylic acid, is recycled to the supply of the apparatus 1.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR7718136 | 1977-06-14 | ||
FR7718136A FR2394512A1 (fr) | 1977-06-14 | 1977-06-14 | Procede de separation d'acide acrylique a partir de ses solutions dans le phosphate de tri-n-butyle |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0000110A1 true EP0000110A1 (de) | 1978-12-20 |
EP0000110B1 EP0000110B1 (de) | 1984-08-29 |
Family
ID=9192057
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP78400011A Expired EP0000110B1 (de) | 1977-06-14 | 1978-06-05 | Verfahren zur Herstellung von Acrylsäure aus deren Lösungen in Tri-n-butylphosphat |
Country Status (10)
Country | Link |
---|---|
US (1) | US4219389A (de) |
EP (1) | EP0000110B1 (de) |
JP (1) | JPS5416421A (de) |
BR (1) | BR7803779A (de) |
CA (1) | CA1103196A (de) |
DE (1) | DE2862438D1 (de) |
ES (1) | ES470776A1 (de) |
FR (1) | FR2394512A1 (de) |
IT (1) | IT1105727B (de) |
SU (1) | SU963461A3 (de) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005035478A2 (de) * | 2003-10-09 | 2005-04-21 | Basf Aktiengesellschaft | Verfahren der rektifikativen auftrennung einer acrylsäure enthaltenden flüssigkeit |
US7560590B2 (en) | 2003-10-09 | 2009-07-14 | Basf Aktiengesellschaft | Rectificative separation of an acrylic acid-containing liquid |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6098794A (ja) * | 1983-11-04 | 1985-06-01 | Matsushita Electric Ind Co Ltd | 圧電型電気音響変換器 |
JPS61159899A (ja) * | 1985-01-08 | 1986-07-19 | Kimio Takahashi | 圧電スピ−カ |
JPS61159900A (ja) * | 1985-01-08 | 1986-07-19 | Kimio Takahashi | 圧電スピ−カ |
JPS61161100A (ja) * | 1985-01-09 | 1986-07-21 | Kimio Takahashi | 圧電スピ−カ |
DE3629093A1 (de) * | 1986-08-27 | 1988-03-10 | Stettner & Co | Piezokeramischer schallwandler |
JPH01176200A (ja) * | 1987-12-29 | 1989-07-12 | Nec Corp | 圧電振動板 |
JPH04105795U (ja) * | 1991-02-23 | 1992-09-11 | 太陽誘電株式会社 | 圧電音響装置 |
FR2735989B1 (fr) * | 1995-06-29 | 1997-08-14 | Rhone Poulenc Nutrition Animal | Procede et installation de purification d'un flux gazeux contenant de l'acroleine |
DE19740252A1 (de) * | 1997-09-12 | 1999-03-18 | Basf Ag | Verfahren zur Herstellung von Acrylsäure und Methacrylsäure |
DE19833049A1 (de) * | 1998-07-22 | 2000-01-27 | Basf Ag | Verfahren zur Herstellung von Acrylsäure |
DE19838783A1 (de) * | 1998-08-26 | 2000-03-02 | Basf Ag | Verfahren zur kontinuierlichen Gewinnung von (Meth)acrylsäure |
NL1013682C2 (nl) * | 1999-11-26 | 2001-05-30 | Purac Biochem Bv | Werkwijze en inrichting voor het zuiveren van een waterige oplossing van melkzuur. |
US20030150705A1 (en) * | 2002-01-08 | 2003-08-14 | Deshpande Sanjeev D. | Acrylic acid recovery utilizing ethyl acrylate and selected co-solvents |
DE10220494A1 (de) * | 2002-05-07 | 2003-11-20 | Basf Ag | Verfahren zur Herstellung einer wässrigen Alkaliacrylat-Lösung |
DE102010064250A1 (de) | 2010-12-28 | 2012-06-28 | Evonik Degussa Gmbh | Verfahren zur Herstellung von Methylmercaptopropionaldehyd |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1558432A (de) * | 1966-12-15 | 1969-02-28 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3092587A (en) * | 1959-07-22 | 1963-06-04 | Bergwerksgesellschaft Hibernia | Process for the production of high percentage solutions of organic peroxides |
FR1359885A (fr) * | 1963-03-21 | 1964-04-30 | Electrochimie Soc | Procédé de fabrication d'acide acrylique glacial |
AT274743B (de) * | 1967-09-28 | 1969-09-25 | Krems Chemie Gmbh | Verfahren und Vorrichtung zur kontinuierlichen Fraktionierung von Tallöl oder andern organischen Mehrstoffgemischen |
US3697387A (en) * | 1968-05-16 | 1972-10-10 | Buss Ag | Process and device for the purification of a mixture of organic substances of high molecular weight |
NL180579C (nl) * | 1972-05-24 | 1987-03-16 | Sumitomo Chemical Co | Werkwijze voor het scheiden van een mengsel bestaande uit acrylzuur, azijnzuur en water. |
US4043873A (en) * | 1973-06-15 | 1977-08-23 | Societa' Italiana Resine S.I.R. S.P.A. | Plural stage recovery of trioxane in a process having a molecular distillation step |
-
1977
- 1977-06-14 FR FR7718136A patent/FR2394512A1/fr active Granted
-
1978
- 1978-06-05 EP EP78400011A patent/EP0000110B1/de not_active Expired
- 1978-06-05 DE DE7878400011T patent/DE2862438D1/de not_active Expired
- 1978-06-12 US US05/914,923 patent/US4219389A/en not_active Expired - Lifetime
- 1978-06-13 JP JP7045478A patent/JPS5416421A/ja active Granted
- 1978-06-13 CA CA305,325A patent/CA1103196A/fr not_active Expired
- 1978-06-13 BR BR787803779A patent/BR7803779A/pt unknown
- 1978-06-13 IT IT49856/78A patent/IT1105727B/it active
- 1978-06-14 ES ES470776A patent/ES470776A1/es not_active Expired
- 1978-06-14 SU SU782627502A patent/SU963461A3/ru active
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1558432A (de) * | 1966-12-15 | 1969-02-28 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2005035478A2 (de) * | 2003-10-09 | 2005-04-21 | Basf Aktiengesellschaft | Verfahren der rektifikativen auftrennung einer acrylsäure enthaltenden flüssigkeit |
WO2005035478A3 (de) * | 2003-10-09 | 2005-09-29 | Basf Ag | Verfahren der rektifikativen auftrennung einer acrylsäure enthaltenden flüssigkeit |
US7560590B2 (en) | 2003-10-09 | 2009-07-14 | Basf Aktiengesellschaft | Rectificative separation of an acrylic acid-containing liquid |
Also Published As
Publication number | Publication date |
---|---|
ES470776A1 (es) | 1979-02-01 |
IT1105727B (it) | 1985-11-04 |
SU963461A3 (ru) | 1982-09-30 |
IT7849856A0 (it) | 1978-06-13 |
FR2394512B1 (de) | 1980-01-18 |
US4219389A (en) | 1980-08-26 |
BR7803779A (pt) | 1979-02-20 |
DE2862438D1 (en) | 1984-10-04 |
JPS5416421A (en) | 1979-02-07 |
JPS5711896B2 (de) | 1982-03-08 |
CA1103196A (fr) | 1981-06-16 |
EP0000110B1 (de) | 1984-08-29 |
FR2394512A1 (fr) | 1979-01-12 |
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