WO1996001248A1 - A process (i) for making potassium formate - Google Patents

A process (i) for making potassium formate Download PDF

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Publication number
WO1996001248A1
WO1996001248A1 PCT/SE1995/000725 SE9500725W WO9601248A1 WO 1996001248 A1 WO1996001248 A1 WO 1996001248A1 SE 9500725 W SE9500725 W SE 9500725W WO 9601248 A1 WO9601248 A1 WO 9601248A1
Authority
WO
WIPO (PCT)
Prior art keywords
reaction
formaldehyde
potassium hydroxide
process according
potassium
Prior art date
Application number
PCT/SE1995/000725
Other languages
French (fr)
Inventor
Carl-Axel SJÖGREEN
Bengt SALLMÉN
Original Assignee
Perstorp Ab
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Perstorp Ab filed Critical Perstorp Ab
Priority to AU29399/95A priority Critical patent/AU2939995A/en
Publication of WO1996001248A1 publication Critical patent/WO1996001248A1/en

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C53/00—Saturated compounds having only one carboxyl group bound to an acyclic carbon atom or hydrogen
    • C07C53/02—Formic acid
    • C07C53/06—Salts thereof
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
    • C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
    • C07C29/14—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of a —CHO group
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C31/00—Saturated compounds having hydroxy or O-metal groups bound to acyclic carbon atoms
    • C07C31/02—Monohydroxylic acyclic alcohols
    • C07C31/04—Methanol
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/41—Preparation of salts of carboxylic acids

Definitions

  • the present invention relates to a process for making potas ⁇ sium formate from formaldehyde and potassium hydroxide.
  • Potassium formate is, among other applications, used as a component in well servicing fluids, such as drilling fluids, for land based as well as offshore oil drilling.
  • Well dril ⁇ ling depends on many factors, such as the performance of used well servicing fluids.
  • Drilling fluids prevent uncontrolled influx of formation fluids into the well, removes formation cuttings from beneath the bit and transports them to the surface, seals exposed permeable formations, maintains the stability of exposed formations, cools and lubricates the bit and the drill string at points of contact with the cased or uncased drill hole and helps to suspend the weight of the drill string and casing.
  • a number of physical and chemical properties including the rheological properties, of drilling fluids are monitored to ensure satisfactory performance.
  • a major problem is created when the viscosity reduces with increasing temperature.
  • a well known method of stabili ⁇ sing rheological properties are the combination of brines, such as chlorides and formates of alkali metals, and poly ⁇ mers, which increases the critical temperature of the poly ⁇ mer.
  • Potassium formate has been found to exhibit excellent stabilising properties at high temperatures resulting in a critical temperature exceeding 200°C, as disclosed in the research report "High Temperature Stabilisation of Xanthan in Drilling Fluids by the Use of Formate Salts" by J.D.
  • Potassium formate is very suitable to use as a component in drilling fluids.
  • the salt provides a high density, required for deep well drilling, has a solubility in water exceeding that of other formates and is environmentally safe.
  • Potassium formate is produced by reacting carbon monoxide with potassium hydroxide in accordance with Reaction I below.
  • the production method according to Reaction I is disclosed in Enclyclopedia of Chemical Technology, 3rd. edition, volume 18, page 938.
  • the reaction is fairly slow and carried out by absorbing carbon monoxide, freed of acidic gases, in 50-80% by weight of potassium hydroxide at 100-200°C and at a pres ⁇ sure of CO > 690 kPa (> 100 psi) .
  • the disadvantages of produ ⁇ cing potassium formate in accordance therewith are obvious and can be summarised: High temperature, high pressure and slow reaction. A high yielding, reliable and industrially applicable process for making potassium formate is presently not available and the availability of said compound is thus limited, being for instance a recovered by-product.
  • Potassium formate can naturally be made by the fundamental but industrially unsuitable or inconvenient reaction between potassium formate and formic acid according to Reaction II below, yielding 1 mole of industrial waste water per mole of potassium formate.
  • Reaction II HCOOH + KOH > HCOOK + H 2 0
  • the present invention provides a high yielding, reliable and fast process for making potassium formate in an industrially suitable and convenient way.
  • the process yields potassium formate and methanol from a reaction between formaldehyde and potassium hydroxide.
  • the reaction is carried out in a liquid, preferably aqueous, state at a molar ratio formaldehyde to potassium hydroxide of 1.0:1.0 to 3.0:1.0, such as 1.5:1.0 to 2.5:1.0 or 1.8:1.0 to 2.2:1.0.
  • the reaction temperature is 0-100°C, such as 5-90°C or 30-70°C. Too high a reaction tem ⁇ perature will cause discolouration.
  • the reaction according to the process of the invention has a major advantage in being irreversible.
  • the reaction occurs in accordance with Reaction III below, whereby 2 moles of form ⁇ aldehyde and 1 mole of potassium hydroxide yield 1 mole of potassium formate and 1 mole of methanol.
  • the reaction is, in preferred embodiments of the process, carried out at a pressure of at most 760, preferably at most 100 mm Hg, whereby methanol yielded during the reaction is allowed to continuously evaporate.
  • the process can preferably be carried out as a batch process, whereby an aqueous potassium hydroxide solution is added to an aqueous formaldehyde solution during at most 24 hours, preferably during 1 to 2 hours.
  • the formaldehyde solution has suitably a formaldehyde percentage of 15-65, preferably 30-45 by weight and corresponding percentage potassium hydroxide is suitably 20-60, preferably 30-50, by weight of the potassium hydroxide solution.
  • the to the addition time subsequent reac ⁇ tion time is normally within the interval of 30 minutes to 6 hours.
  • the process is, when an excess of potassium hydroxide over formedehyde is used, suitably terminated by a neutrali ⁇ sation with an acid, such as formic acid.
  • the process according to the invention normally converts at least 99% of the theoretically convertible formaldehyde into potassium formate. This exceptionally high degree of conver ⁇ sion results from the fact that the reaction, as disclosed above, is irreversible.
  • Yielded methanol which during the process preferably but not necessarily is evaporated, can suitably be recovered and used for preparation of formaldehyde and thus used as raw material for further production of potassium formate according to the the process of the present invention.
  • An excess of formaldehyde or potassium hydroxide can be reco ⁇ vered using known methods and reused in the process of the invention.
  • Excess of potassium hydroxide can furthermore and as disclosed above be neutralised with an acid, such as for ⁇ mic acid, thus giving a potassium salt, which per se can be a separate product or be added to the amount of potassium formate resulting from the process.
  • the major advantages of the process according to the present invention include a fast and simple reaction, a low reaction temperature, atmospheric or reduced pressure, a high degree of conversion and no by-products creating waste problems; all enambling a safe and reliable as well as industrially suit ⁇ able and convenient production of large quantities of potas ⁇ sium formate.
  • reaction vessel was subsequent the addition of potassium hydroxide heated to 40°C and the pressure was reduced to 20 mm Hg. Methanol formed during the reaction was continuously evaporated and collected in the receiver.
  • reaction was allowed to continue at 40°C and 20 mm Hg for 4 hours.
  • pressure was now adjusted to approximately 760 mm Hg (atmospheric pressure) and the excess of potassium hydroxide in obtained reaction mixture was neutralised with 10.8 g of formic acid and cooled to room temperature.
  • the reaction vessel contained 183.5 g of an aqueous reaction mixture holding by weight 55% of potassium formate, 0.01% of formaldehyde and 0.03% of methanol.
  • the recovered quantity of potassium formate can be derived as follows:

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

A process for making potassium formate, whereby potassium formate and methanol yield from a reaction between formaldehyde and potassium hydroxide. The reaction is carried out in a liquid, preferably aqueous, state at a molar ratio formaldehyde to potassium hydroxide of 1.0:1.0 to 3.0:1.0 and at a temperature of 0-100 °C.

Description

A PROCESS (I) FOR MAKING POTASSIUM FORMATE
The present invention relates to a process for making potas¬ sium formate from formaldehyde and potassium hydroxide.
Potassium formate is, among other applications, used as a component in well servicing fluids, such as drilling fluids, for land based as well as offshore oil drilling. Well dril¬ ling depends on many factors, such as the performance of used well servicing fluids. Drilling fluids prevent uncontrolled influx of formation fluids into the well, removes formation cuttings from beneath the bit and transports them to the surface, seals exposed permeable formations, maintains the stability of exposed formations, cools and lubricates the bit and the drill string at points of contact with the cased or uncased drill hole and helps to suspend the weight of the drill string and casing. A number of physical and chemical properties including the rheological properties, of drilling fluids are monitored to ensure satisfactory performance. A major problem is created when the viscosity reduces with increasing temperature. The rheological properties of poly¬ mers, included in drilling fluids as for instance viscosi- fiers, are often substantially degraded or even lost with an increasing temperature. A well known method of stabili¬ sing rheological properties are the combination of brines, such as chlorides and formates of alkali metals, and poly¬ mers, which increases the critical temperature of the poly¬ mer. Potassium formate has been found to exhibit excellent stabilising properties at high temperatures resulting in a critical temperature exceeding 200°C, as disclosed in the research report "High Temperature Stabilisation of Xanthan in Drilling Fluids by the Use of Formate Salts" by J.D. Downs - Koninklijke/Shell Exploratie en Produktie Laboratorium, The Netherlands - Physical Chemistry of Coloids and Interfaces in Production, Paris 1992 pages 197-202. J.D. Downs gives in said paper a detailed disclosure of formates and their stabi¬ lising effect. Furthermore, the European Patent Applications 269 939 and 572 113 also disclose the use of formates in drilling fluids.
Potassium formate is very suitable to use as a component in drilling fluids. The salt provides a high density, required for deep well drilling, has a solubility in water exceeding that of other formates and is environmentally safe.
Potassium formate is produced by reacting carbon monoxide with potassium hydroxide in accordance with Reaction I below.
Reaction I: CO + KOH > HCOOK
The production method according to Reaction I is disclosed in Enclyclopedia of Chemical Technology, 3rd. edition, volume 18, page 938. The reaction is fairly slow and carried out by absorbing carbon monoxide, freed of acidic gases, in 50-80% by weight of potassium hydroxide at 100-200°C and at a pres¬ sure of CO > 690 kPa (> 100 psi) . The disadvantages of produ¬ cing potassium formate in accordance therewith are obvious and can be summarised: High temperature, high pressure and slow reaction. A high yielding, reliable and industrially applicable process for making potassium formate is presently not available and the availability of said compound is thus limited, being for instance a recovered by-product.
Potassium formate can naturally be made by the fundamental but industrially unsuitable or inconvenient reaction between potassium formate and formic acid according to Reaction II below, yielding 1 mole of industrial waste water per mole of potassium formate. Reaction II: HCOOH + KOH > HCOOK + H20
The present invention provides a high yielding, reliable and fast process for making potassium formate in an industrially suitable and convenient way. The process yields potassium formate and methanol from a reaction between formaldehyde and potassium hydroxide. The reaction is carried out in a liquid, preferably aqueous, state at a molar ratio formaldehyde to potassium hydroxide of 1.0:1.0 to 3.0:1.0, such as 1.5:1.0 to 2.5:1.0 or 1.8:1.0 to 2.2:1.0. The reaction temperature is 0-100°C, such as 5-90°C or 30-70°C. Too high a reaction tem¬ perature will cause discolouration.
The reaction according to the process of the invention has a major advantage in being irreversible. The reaction occurs in accordance with Reaction III below, whereby 2 moles of form¬ aldehyde and 1 mole of potassium hydroxide yield 1 mole of potassium formate and 1 mole of methanol.
Reaction III: 2 HCHO + KOH > HCOOK + CHgOH
The reaction is, in preferred embodiments of the process, carried out at a pressure of at most 760, preferably at most 100 mm Hg, whereby methanol yielded during the reaction is allowed to continuously evaporate.
The process can preferably be carried out as a batch process, whereby an aqueous potassium hydroxide solution is added to an aqueous formaldehyde solution during at most 24 hours, preferably during 1 to 2 hours. The formaldehyde solution has suitably a formaldehyde percentage of 15-65, preferably 30-45 by weight and corresponding percentage potassium hydroxide is suitably 20-60, preferably 30-50, by weight of the potassium hydroxide solution. The to the addition time subsequent reac¬ tion time is normally within the interval of 30 minutes to 6 hours. The process is, when an excess of potassium hydroxide over formedehyde is used, suitably terminated by a neutrali¬ sation with an acid, such as formic acid.
Said addition and reaction time as well as said percentages and neutralisation are of course valid also for other embodi¬ ments of the invention not being batch processes, such as a continuous process.
*
The process according to the invention normally converts at least 99% of the theoretically convertible formaldehyde into potassium formate. This exceptionally high degree of conver¬ sion results from the fact that the reaction, as disclosed above, is irreversible.
Yielded methanol, which during the process preferably but not necessarily is evaporated, can suitably be recovered and used for preparation of formaldehyde and thus used as raw material for further production of potassium formate according to the the process of the present invention.
An excess of formaldehyde or potassium hydroxide can be reco¬ vered using known methods and reused in the process of the invention. Excess of potassium hydroxide can furthermore and as disclosed above be neutralised with an acid, such as for¬ mic acid, thus giving a potassium salt, which per se can be a separate product or be added to the amount of potassium formate resulting from the process.
The major advantages of the process according to the present invention include a fast and simple reaction, a low reaction temperature, atmospheric or reduced pressure, a high degree of conversion and no by-products creating waste problems; all enambling a safe and reliable as well as industrially suit¬ able and convenient production of large quantities of potas¬ sium formate. These and other objects and the attendant advantages will be more fully understood from the detailed description, taken in conjunction with below embodiment example, wherein potassium formate is prepared by an embodiment of the process according to the present invention.
EXAMPLE
133.4 g of an aqueous formaldehyde solution (2 moles of form¬ aldehyde) having a formaldehyde content of 45% by weight were charged in a reaction vessel equipped with a cooler provided with a receiver, a stirrer, a pressure gauge and means for the heating and cooling of the vessel. 146.4 g of an aqueous potassium hydroxide solution (1.2 mole of potassium hydroxi¬ de) having a potassium hydroxide content of 46% by weight were during 20 minutes added to the formaldehyde solution. The reaction mixture was during the addition stirred and the reaction vessel was water cooled.
The reaction vessel was subsequent the addition of potassium hydroxide heated to 40°C and the pressure was reduced to 20 mm Hg. Methanol formed during the reaction was continuously evaporated and collected in the receiver.
The reaction was allowed to continue at 40°C and 20 mm Hg for 4 hours. The pressure was now adjusted to approximately 760 mm Hg (atmospheric pressure) and the excess of potassium hydroxide in obtained reaction mixture was neutralised with 10.8 g of formic acid and cooled to room temperature.
The reaction vessel contained 183.5 g of an aqueous reaction mixture holding by weight 55% of potassium formate, 0.01% of formaldehyde and 0.03% of methanol. The receiver contained 128 g of an aqueous mixture holding by weight 25% of methanol (« 32 g - theoretical amount = 32.0 g) and 1.7% of formaldehyde.
The volatile content of the reaction mixture was vaporised and 100.8 g of potassium formate recovered.
The recovered quantity of potassium formate can be derived as follows:
16.8 g - yielded from neutralisation with formic acid.
84.0 g - yielded from the reaction between formaldehyde and potassium hydroxide. Equals a conversion of > 99.8% of the formaldehyde to potassium formate (possible losses in connection with reaction, material hand¬ ling and analyses are not regarded) . The theoretical amount is 84.1 g = 1 mole.
While a particular and preferred embodiment of the invention has been shown, it will be understood, of course, that the invention is not limited thereto since many modifications may be made, and it is, therefore, contemplated to cover by the appended claims any such modifications as fall within the true spirit and scope of the invention.

Claims

1. A process for making potassium formate c h a r a c t e r i s e d i n, that the potassium formate and methanol yield from a reaction between formaldehyde and potassium hydroxide, the reaction being carried out in a liquid, preferably aqueous, state at a molar ratio formaldehyde to potassium hydroxide of 1.0:1.0 to 3.0:1.0, such as 1.5:1.0 to 2.5:1.0 or 1.8:,1.0 to 2.2:1.0, and at a temperature of 0-100°C, preferably 30-70°C.
2. A process according to claim 1 c h a r a c t e r i s e d i n, that the reaction is carried out at a pressure of at most 760, preferably at most 100, mm Hg.
3. A process according to claim 1 or 2 c h a r a c t e r i s e d i n, that the process is a batch process, whereby an aqueous potas¬ sium hydroxide solution is added to an aqueous formalde¬ hyde solution.
4. A process according to claim 3 c h a r a c t e r i s e d i n, that the potassium hydroxide solution is added to the formalde¬ hyde solution during at most 24 hours, preferably during 1 to 2 hours.
5. A process according to claim 3 or 4 c h a r a c t e r i s e d i n, that the formaldehyde solution has a formaldehyde percentage of 15-65%, preferably 30-45%, by weight.
6. A process according to any of the claims 3 - 5 c h a r a c t e r i s e d i n, that the potassium hydroxide solution has a potassium hydroxide percentage of 20-60%, preferably 30-50%, by weight.
7. A process according to any of the claims 3 - 6 c h a r a c t e r i s e d i n, that the process is carried out at a molar ratio formaldehyde to potassium hydroxide of 1:1 to 2:1 and that the process is terminated by neutralisation with an acid, preferably formic acid.
8. A process according to any of the claims 1 - 7 c h a r a c t e r i s e d i n, that the methanol yielded during the reaction is allowed to continuously evaporate.
9. A process according to any of the claims 1 - 8 c h a r a c t e r i s e d i n, that at least 99% of theoretically convertible formaldehyde is converted into potassium formate.
PCT/SE1995/000725 1994-07-04 1995-06-15 A process (i) for making potassium formate WO1996001248A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
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Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9402347-0 1994-07-04
SE9402347A SE9402347L (en) 1994-07-04 1994-07-04 Process for the manufacture of potassium formate I

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003043967A1 (en) * 2001-11-08 2003-05-30 Mks Marmara Entegre Kimya San. A.S. Production of potassium formate
WO2011113748A2 (en) 2010-03-17 2011-09-22 Addcon Europe Gmbh Method for recycling the materials of aqueous mixtures
CN116041141A (en) * 2023-02-10 2023-05-02 成都中科凯特科技有限公司 Method for synthesizing methanol by heterogeneous catalytic formaldehyde transfer hydrogenation

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4126730A1 (en) * 1991-08-13 1993-02-18 Degussa Prepn. of calcium formate from calcium hydroxide and formaldehyde - uses calcium hydroxide with short solubility time, in presence of inhibitor for auto-condensation of formaldehyde
EP0572113A1 (en) * 1992-05-29 1993-12-01 BP Chemicals Limited Aqueous brines

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4126730A1 (en) * 1991-08-13 1993-02-18 Degussa Prepn. of calcium formate from calcium hydroxide and formaldehyde - uses calcium hydroxide with short solubility time, in presence of inhibitor for auto-condensation of formaldehyde
EP0572113A1 (en) * 1992-05-29 1993-12-01 BP Chemicals Limited Aqueous brines

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003043967A1 (en) * 2001-11-08 2003-05-30 Mks Marmara Entegre Kimya San. A.S. Production of potassium formate
US6849764B2 (en) 2001-11-08 2005-02-01 Mks Marmara Entegre Kimya San A.S. Production of potassium formate
WO2011113748A2 (en) 2010-03-17 2011-09-22 Addcon Europe Gmbh Method for recycling the materials of aqueous mixtures
DE102010011691A1 (en) * 2010-03-17 2011-09-22 Addcon Europe Gmbh Process for the recycling of aqueous mixtures
WO2011113748A3 (en) * 2010-03-17 2011-12-22 Addcon Europe Gmbh Method for recycling the materials of aqueous mixtures comprising formic acid, formaldehyde and methanol
CN116041141A (en) * 2023-02-10 2023-05-02 成都中科凯特科技有限公司 Method for synthesizing methanol by heterogeneous catalytic formaldehyde transfer hydrogenation
CN116041141B (en) * 2023-02-10 2024-04-30 成都中科凯特科技有限公司 Method for synthesizing methanol by heterogeneous catalytic formaldehyde transfer hydrogenation

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Publication number Publication date
SE9402347L (en) 1996-01-05
AU2939995A (en) 1996-01-25
SE9402347D0 (en) 1994-07-04

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