WO2004078691A1 - Verfahren zur thermischen stabilisierung hochkonzentrierter formaldehydlösungen - Google Patents
Verfahren zur thermischen stabilisierung hochkonzentrierter formaldehydlösungen Download PDFInfo
- Publication number
- WO2004078691A1 WO2004078691A1 PCT/EP2004/002181 EP2004002181W WO2004078691A1 WO 2004078691 A1 WO2004078691 A1 WO 2004078691A1 EP 2004002181 W EP2004002181 W EP 2004002181W WO 2004078691 A1 WO2004078691 A1 WO 2004078691A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- highly concentrated
- concentrated formaldehyde
- temperature
- formaldehyde
- formaldehyde solution
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C47/00—Compounds having —CHO groups
- C07C47/02—Saturated compounds having —CHO groups bound to acyclic carbon atoms or to hydrogen
- C07C47/04—Formaldehyde
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/78—Separation; Purification; Stabilisation; Use of additives
- C07C45/81—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C45/82—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
Definitions
- the invention relates to a method for stabilizing highly concentrated formaldehyde solutions against solid precipitation.
- Formaldehyde is an important industrial chemical and is used to manufacture numerous industrial products and consumables.
- Formaldehyde is currently used in over 50 industries, mainly in the form of aqueous solutions or synthetic resins containing formaldehyde.
- Commercially available aqueous formaldehyde solutions have total concentrations of 20 to 55% by weight of formaldehyde in the form of monomeric formaldehyde, methylene glycol and oligomeric polyoxymethylene glycols.
- aqueous formaldehyde solution also refers to formaldehyde solutions which contain practically no free water, but essentially only water which is chemically bound in the form of methylene glycol or in the terminal OH groups of the polyoxymethylene glycols. This is particularly the case with concentrated formaldehyde solutions.
- Polyoxymethylene glycols can have, for example, two to nine oxymethylene units.
- Dioxymethylene glycol, trioxymethylene glycol, tetraoxymethylene glycol, pentaoxymethylene glycol, hexaoxymethylene glycol, heptaoxymethylene glycol, octaoxymethylene glycol and nonaoxymethylene glycol can therefore be present in aqueous formaldehyde solutions.
- the distribution depends on the concentration.
- the maximum of the distribution in dilute formaldehyde solutions is with homologues of short chain length, while in more concentrated formaldehyde solutions it is with homologues of higher chain length.
- An equilibrium shift towards longer-chain (higher molecular weight) polyoxymethylene glycols can take place by dehydration, for example by distillation with a superimposed condensation reaction in a film evaporator. The equilibrium is set by the finite speed intermolecular condensation of methylene glycol and low molecular weight polyoxymethylene glycols with elimination of water to higher molecular weight polyoxymethylene glycols.
- the highly concentrated formaldehyde solutions obtained by dehydration are unstable in the sense that after a certain period of time a solid fails.
- the precipitating solids are essentially the longer-chain formaldehyde oligomers or polyoxymethylene glycols described above.
- the highly concentrated formaldehyde solutions can be stabilized in order to avoid solid precipitation by adding stabilizers, for example methanol.
- stabilizers for example methanol.
- the presence of stabilizers is often undesirable when the highly concentrated formaldehyde solutions are used further.
- the object of the invention is to provide a method for stabilizing highly concentrated formaldehyde solutions against solid precipitation.
- the object is achieved by a process for stabilizing highly concentrated formaldehyde solutions with a CH 2 O content> 70% by weight against solid precipitation, in which the highly concentrated formaldehyde solution is heated to a temperature of at least 5 ° C./min immediately after production 80 ° C to a maximum of 200 ° C and stored at a temperature in this area.
- the highly concentrated formaldehyde solution is heated immediately after production at a heating rate of at least 5 ° C./min to a temperature of at least 80 ° C. to at most 200 ° C. and stored at a temperature in this area. Once a temperature of at least 80 ° C has been reached, heating can continue with a lower heating rate or the formaldehyde solution can be left at the temperature reached. It can also be cooled from a higher temperature that has already been reached to a lower temperature as long as the temperature does not fall below 80 ° C. for a long time. It is also crucial that a temperature of 200 ° C is not significantly exceeded. At higher temperatures, the highly concentrated formaldehyde solution leads to degradation reactions, for example through Cannizzaro disproportionation or decomposition to CO and H 2 .
- the highly concentrated formaldehyde solution obtained for example, at 20 to 60 ° C. is heated at the specified heating rate after no more than 60 min, preferably after no more than 5 min.
- the concentration of the formaldehyde solution can be> 70% by weight,> 75% by weight or even> 80% by weight of CH 2 O.
- Formaldehyde solutions of this concentration can be obtained by any method, but they are preferably obtained by distillation. It is particularly preferred to use the methods described in EP-A 1 063 221 and in the unpublished German patent application DE 101 54 187.2.
- the heating rate is preferably at least 10 ° C./min.
- a heating rate of at least 10 ° C./min is particularly preferred if the pH of the solution is less than 3 or greater than 6.
- the specified heating rate is preferably used to heat to at least 90 ° C., particularly preferably to at least 100 ° C., and this temperature is then no longer below.
- the final temperature is preferably a maximum of 150 ° C., particularly preferably a maximum of 135 ° C.
- the pH of the highly concentrated formaldehyde solution is usually in the range from 1 to 10, preferably from 2 to 9, particularly preferably from 3 to 6.
- the pH can be adjusted to the desired range by adding buffer substances, for example a formate buffer become.
- the rapid heating of the highly concentrated formaldehyde solutions according to the invention can take place in any open or closed systems. Suitable are, for example, stirred kettles which are heated by means of double jackets or coils (inside or outside). Apparatuses with heat exchanger characteristics are particularly preferred, for example tube bundle heat exchangers, plate apparatuses or spiral tubes. These can be operated in cocurrent, countercurrent or crossflow. The heating can take place with any media, for example with condensing steam or single-phase with liquids or gases.
- the above-mentioned apparatuses can be designed and operated without difficulty so that the required heating rate is set.
- the highly concentrated formaldehyde solution can be stored in any open or closed system.
- “Storage” in the sense of the present invention is to be understood to mean that the highly concentrated formaldehyde solution is left in the temperature window of 80 to 200 ° C. for a certain period of time. This period can be very short, for example only a few minutes until the highly concentrated formaldehyde solution is used in one However, the period can also be very long, for example days, weeks or months.
- the storage is preferably carried out in a simple container with an internal heat exchanger.
- the solution can also be filled into drums, containers or tank wagons and sent, while the temperature must be kept at> 80 ° C.
- the highly concentrated formaldehyde solutions are preferably produced in a film evaporator or a spiral tube evaporator.
- a suitable film evaporator is shown in Fig. 1. It is a thin film evaporator.
- the feed 1, consisting of raw solution (starting material mixture) and possibly a recycle stream, is first fed to a liquid distributor 2. This distributes the raw solution to an evaporator surface 3.
- the evaporator surface 3 heat exchanger surface
- the evaporator surface 3 is usually cylindrical in shape, but can also be at least partially conical in shape. It stands with the inside of a heating jacket 4, which is used to supply heat Evaporator surface 3 ensures thermal contact.
- the liquid distributor 2 contributes to the fact that the inlet resolution is distributed uniformly over the circumference of the evaporator surface 3.
- Rotating wiper blades 5 then distribute the solution further over the evaporator surface 3, ensure the maintenance and promotion of a liquid film on the evaporator surface 3 and contribute to the intensification of the heat and mass transport in the liquid.
- These wiper blades 5 are driven by a drive device 6.
- the liquid film can be kept thin or jammed. This makes it possible to change the residence time or the residence time distribution of the solution in the film evaporator.
- the typical residence time of the solution in the film evaporator is between 1 s and 10 min, preferably between 2 s and 2 min.
- a heating medium e.g. Steam
- led into the heating jacket This heats up the evaporator surface.
- Cooled heating medium, e.g. condensed water in the case of steam as a heating medium is discharged via the heating medium outlet 8.
- the resulting vapors enter a phase separation chamber 9 and from there into a droplet separator 10. Liquid droplets entrained with the vapors are removed from the gas phase and returned to the liquid (solution).
- the concentrate 13 is discharged from the phase separation chamber 9 in a suitable manner, while the vapor 12 is withdrawn from the droplet separator 10.
- the vapor is introduced into a condenser, not shown, where it condenses at least partially to form a condensate.
- Condensate from the vapor 12 is low in polyoxymethylene glycols and rich in formaldehyde and methylene glycol. In this way there are two factions, namely Concentrate 13 and (partial) condensate formed from the vapor 12, in which certain components of the raw solution 1 originally supplied are selectively enriched.
- the condenser can be integrated into the evaporation body, which results in a shorter residence time of the evaporated components in the vapor phase and in a more compact design.
- Suitable operating conditions for the film evaporator are generally a temperature between 10 ° C. and 200 ° C., preferably between 50 ° C. and 150 ° C., at an absolute pressure of 0.5 mbar to 2 bar, preferably 30 mbar to 1.5 bar preferably 60 mbar to 1.0 bar.
- the temperature of the highly concentrated formaldehyde solution leaving the film evaporator as the outlet is usually from 20 to 60 ° C.
- an apparatus can also be used on the evaporation surface without mechanically influencing the liquid film.
- the heat transfer surface of this falling film or downflow evaporator can be designed as tubes or plates.
- a film evaporator can be used in various operating modes.
- 2 shows a schematic overview of the possible modes of operation.
- the actual film evaporator is labeled 15 and a vapor separator (i.e. phase separation chamber with droplet separator) 16.
- Both the film evaporator 15 and the vapor separator 16 can deviate from the special design, as shown in FIG. 1, and have further inflows and outflows compared to FIG. 1.
- VI, V2 and V3 denote vaporous streams, all other streams are usually liquid.
- the film evaporator 15 can be operated in a single pass or in a recycle mode with regard to the escaping, non-evaporated liquid.
- the circulation U is technically necessary for operation in a cycle mode.
- the film evaporator can have side draws at a suitable point, via which liquid fractions with a certain degree of enrichment can be removed.
- Several evaporators can also be connected in series to form an evaporator cascade, the liquid, concentrated outlet of one evaporator - possibly after removal of a side stream - forming the inlet for the next evaporator in the evaporator cascade.
- the high-concentration formaldehyde solutions obtained are stabilized according to the invention, for example in one of the above-mentioned apparatuses, and after storage can be used for a large number of chemical reactions.
- Examples of such implementations are • the conversion of acetylene with formaldehyde solution in a Reppe reaction to propinol and butynediol, the latter being able to be hydrogenated to butanediol;
- a head of a liquid-heated laboratory thin-film evaporator with an inner diameter of 50 mm and a wiped length of 300 mm is given an aqueous formaldehyde solution consisting of 30% by weight of formaldehyde, 69% by weight of water and 1% by weight of methanol.
- the feed stream is 1 1 / h.
- the heating jacket temperature of the thin-film evaporator is set to 120 ° C and the pressure in the interior to 100 mbar.
- an aqueous formaldehyde solution consisting of about 80% by weight of formaldehyde and 20% by weight of water and less than 0.2% by weight of methanol at about 55 ° C. is obtained in the bottom of the thin-film evaporator.
- the heat exchanger used is a serpentine heat exchanger made of glass with a jacket space length of 400 mm.
- the length of the pipe coil is 3.2 m, its inner diameter 6 mm.
- the formaldehyde solution is promoted by the heat exchanger.
- the jacket space of the apparatus is heated with a large volume of triethylene glycol at 130 ° C.
- the solution leaves the heat exchanger at a temperature of 120 ° C.
- the heating rate of the tube-side medium achieved under these conditions is approximately 13 ° C./min, which is above the required minimum rate of 5 ° C./min. Under the process conditions mentioned, there is no solid failure at any point in the apparatus.
- the formaldehyde solution leaving the heat exchanger is water-clear and liquid and can be kept stable at 120 ° C without loss of solid.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
Abstract
Description
Claims
Priority Applications (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA002517564A CA2517564A1 (en) | 2003-03-04 | 2004-03-04 | Method for thermal stabilization of highly concentrated formaldehyde solutions |
AU2004218302A AU2004218302A1 (en) | 2003-03-04 | 2004-03-04 | Method for thermal stabilization of highly concentrated formaldehyde solutions |
MXPA05009237A MXPA05009237A (es) | 2003-03-04 | 2004-03-04 | Estabilizacion termica de soluciones de formaldehido de concentracion elevada. |
EP04717067A EP1601639A1 (de) | 2003-03-04 | 2004-03-04 | Verfahren zur thermischen stabilisierung hochkonzentrierter formaldehydlösungen |
US10/547,857 US7273955B2 (en) | 2003-03-04 | 2004-03-04 | Method for thermal stabilization of highly concentrated formaldehyde solutions |
BRPI0408031-9A BRPI0408031A (pt) | 2003-03-04 | 2004-03-04 | processo para estabilizar soluções de formaldeìdo de alta concentração, solução de alta concentração de formaldeìdo, e, uso da mesma |
JP2006500046A JP2006515342A (ja) | 2003-03-04 | 2004-03-04 | 高濃縮ホルムアルデヒド溶液の熱安定化法 |
NO20054345A NO20054345L (no) | 2003-03-04 | 2005-09-20 | Fremgangsmate for termisk stabilisering av hoykonsentrerte formaldehydlosninger |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE10309286A DE10309286A1 (de) | 2003-03-04 | 2003-03-04 | Verfahren zur thermischen Stabilisierung hochkonzentrierter Formaldehydlösungen |
DE10309286.2 | 2003-03-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2004078691A1 true WO2004078691A1 (de) | 2004-09-16 |
Family
ID=32864081
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2004/002181 WO2004078691A1 (de) | 2003-03-04 | 2004-03-04 | Verfahren zur thermischen stabilisierung hochkonzentrierter formaldehydlösungen |
Country Status (13)
Country | Link |
---|---|
US (1) | US7273955B2 (de) |
EP (1) | EP1601639A1 (de) |
JP (1) | JP2006515342A (de) |
KR (1) | KR20050106071A (de) |
CN (1) | CN1756732A (de) |
AU (1) | AU2004218302A1 (de) |
BR (1) | BRPI0408031A (de) |
CA (1) | CA2517564A1 (de) |
DE (1) | DE10309286A1 (de) |
MX (1) | MXPA05009237A (de) |
MY (1) | MY136772A (de) |
NO (1) | NO20054345L (de) |
WO (1) | WO2004078691A1 (de) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010121990A2 (de) | 2009-04-20 | 2010-10-28 | Basf Se | Verfahren zur herstellung von mda über die stufe des aminals |
WO2014184098A1 (de) | 2013-05-14 | 2014-11-20 | Basf Se | Verfahren zur herstellung von vinylidencarbonsäure(ester)n durch umsetzung von formaldehyd mit alkylcarbonsäure(estern)n |
DE102013008207A1 (de) | 2013-05-14 | 2014-11-20 | Basf Se | Verfahren zur Herstellung von Acrylsäure mit hoher Raum-Zeit-Ausbeute |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7670191B2 (en) * | 2007-04-20 | 2010-03-02 | Hon Hai Precision Ind. Co., Ltd. | Extension/expansion to universal serial bus connector |
US10377689B2 (en) | 2016-11-17 | 2019-08-13 | OME Technologies GmbH | Process for preparing polyoxymethylene dimethyl ethers from formaldehyde and methanol in aqueous solutions |
DE102016222657A1 (de) | 2016-11-17 | 2018-05-17 | OME Technologies GmbH | Verfahren zur Herstellung von Polyoxymethylendimethylethern aus Formaldehyd und Methanol in wässrigen Lösungen |
DE102020118386A1 (de) | 2020-07-13 | 2022-01-13 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung eingetragener Verein | Verfahren zur Herstellung von Polyoxymethylendimethylethern |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2440732A (en) * | 1945-07-19 | 1948-05-04 | Du Pont | Aqueous formaldehyde storage |
GB1190682A (en) * | 1967-03-23 | 1970-05-06 | Italiane Resine S P A Soc | Concentration of Aqueous Formaldehyde Solutions. |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4247487A (en) * | 1972-12-26 | 1981-01-27 | E. I. Du Pont De Nemours And Company | Stabilized formaldehyde solutions |
IT1067560B (it) * | 1976-11-19 | 1985-03-16 | Montedison Spa | Processo per la preparazione di sospensioni acquose stabili di formaldeide e prodotti otenuti |
US4085079A (en) * | 1977-02-02 | 1978-04-18 | Monsanto Company | Formaldehyde solutions stabilized with interpolymers of vinyl acetate, vinyl acetal and vinyl alcohol |
US4289912A (en) * | 1980-05-02 | 1981-09-15 | Celanese Corporation | Stabilization of liquid paraformaldehyde |
JPH09278700A (ja) * | 1996-04-17 | 1997-10-28 | Katayama Chem Works Co Ltd | 脂肪族アルデヒド水性溶液、その安定剤及び安定化方法 |
DE19925870A1 (de) * | 1999-06-07 | 2000-12-14 | Basf Ag | Verfahren zur Umsetzung einer ein Gemisch enthaltenden Lösung |
ES2303557T3 (es) * | 2001-11-05 | 2008-08-16 | Basf Se | Disolucion de formaldehido altamente concentrada, su elaboracion y reaccion. |
DE10154187A1 (de) | 2001-11-05 | 2003-05-15 | Basf Ag | Hochkonzentrierte Formaldehydlösung, deren Herstellung und Umsetzung |
DE10158813A1 (de) | 2001-11-30 | 2003-06-12 | Basf Ag | Verfahren zur Herstellung von Oxymethylenhomo- oder -copolymeren |
-
2003
- 2003-03-04 DE DE10309286A patent/DE10309286A1/de not_active Withdrawn
-
2004
- 2004-03-03 MY MYPI20040733A patent/MY136772A/en unknown
- 2004-03-04 AU AU2004218302A patent/AU2004218302A1/en not_active Abandoned
- 2004-03-04 JP JP2006500046A patent/JP2006515342A/ja not_active Withdrawn
- 2004-03-04 CA CA002517564A patent/CA2517564A1/en not_active Abandoned
- 2004-03-04 EP EP04717067A patent/EP1601639A1/de not_active Withdrawn
- 2004-03-04 BR BRPI0408031-9A patent/BRPI0408031A/pt not_active IP Right Cessation
- 2004-03-04 MX MXPA05009237A patent/MXPA05009237A/es unknown
- 2004-03-04 US US10/547,857 patent/US7273955B2/en not_active Expired - Fee Related
- 2004-03-04 KR KR1020057016331A patent/KR20050106071A/ko not_active Application Discontinuation
- 2004-03-04 WO PCT/EP2004/002181 patent/WO2004078691A1/de active Search and Examination
- 2004-03-04 CN CNA200480005844XA patent/CN1756732A/zh active Pending
-
2005
- 2005-09-20 NO NO20054345A patent/NO20054345L/no unknown
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2440732A (en) * | 1945-07-19 | 1948-05-04 | Du Pont | Aqueous formaldehyde storage |
GB1190682A (en) * | 1967-03-23 | 1970-05-06 | Italiane Resine S P A Soc | Concentration of Aqueous Formaldehyde Solutions. |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010121990A2 (de) | 2009-04-20 | 2010-10-28 | Basf Se | Verfahren zur herstellung von mda über die stufe des aminals |
WO2010121990A3 (de) * | 2009-04-20 | 2010-12-23 | Basf Se | Verfahren zur herstellung von methylendiphenyldiamin (mda) über die stufe des aminals |
CN102405208A (zh) * | 2009-04-20 | 2012-04-04 | 巴斯夫欧洲公司 | 通过缩醛胺阶段制备亚甲基二苯基二胺(mda)的方法 |
US8710267B2 (en) | 2009-04-20 | 2014-04-29 | Basf Se | Process for preparing MDA via the stage of the aminal |
CN102405208B (zh) * | 2009-04-20 | 2015-02-25 | 巴斯夫欧洲公司 | 通过缩醛胺阶段制备亚甲基二苯基二胺(mda)的方法 |
WO2014184098A1 (de) | 2013-05-14 | 2014-11-20 | Basf Se | Verfahren zur herstellung von vinylidencarbonsäure(ester)n durch umsetzung von formaldehyd mit alkylcarbonsäure(estern)n |
DE102013008207A1 (de) | 2013-05-14 | 2014-11-20 | Basf Se | Verfahren zur Herstellung von Acrylsäure mit hoher Raum-Zeit-Ausbeute |
WO2014184099A1 (de) | 2013-05-14 | 2014-11-20 | Basf Se | Verfahren zur herstellung von acrylsäure mit hoher raum-zeit-ausbeute |
DE102013008206A1 (de) | 2013-05-14 | 2014-11-20 | Basf Se | Verfahren zur Herstellung von Vinylidencarbonsäure(ester)n durch Umsetzung von Formaldehyd mit Alkylcarbonsäure(estern)n |
Also Published As
Publication number | Publication date |
---|---|
US20060084827A1 (en) | 2006-04-20 |
CN1756732A (zh) | 2006-04-05 |
MY136772A (en) | 2008-11-28 |
JP2006515342A (ja) | 2006-05-25 |
AU2004218302A1 (en) | 2004-09-16 |
MXPA05009237A (es) | 2005-10-19 |
KR20050106071A (ko) | 2005-11-08 |
CA2517564A1 (en) | 2004-09-16 |
NO20054345L (no) | 2005-09-26 |
BRPI0408031A (pt) | 2006-02-14 |
US7273955B2 (en) | 2007-09-25 |
DE10309286A1 (de) | 2004-09-16 |
EP1601639A1 (de) | 2005-12-07 |
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