DE102014109637A1 - Liquid formulation - Google Patents

Abstract

The present invention relates to nonaqueous liquid formulations of aminoalkylenephosphonic acids and their corresponding salts, and to a process for the preparation thereof and their use for the preparation of homogeneous solutions in low molecular weight mono- and / or dihydric alcohols, the liquid formulation containing at least the following components: a) a Aminoalkylenphosphonic acid or its corresponding alkali metal salt, with a content in the range of 5 to 35% by mass, b) a polyhydric alcohol having a C2 to C6 carbon skeleton, c) a solubilizer, wherein the mass ratio of polyhydric alcohol to solubilizer in the range from 80: 2 to 60:20 and to processes for the preparation of these, wherein particularly advantageously the remaining amount of water remaining in the liquid formulation is below a concentration limit, which would have adverse effects for further technical application.

Description

The present invention relates to homogeneous, nonaqueous liquid formulations of aminoalkylenephosphonic acids and their corresponding salts in an organic system and to a process for the preparation thereof and their use for the preparation of homogeneous solutions in low molecular weight mono- and / or dihydric alcohols.

Aminoalkylenephosphonic acids have been produced worldwide for many decades on the order of about 100,000 tons of active substance molecule per year and used in a wide variety of applications. The reason for the range of use of the aminoalkylenephosphonic acids is their very good complexing power for a large number of metal ions and excellent stabilization of water hardness, combined with a pronounced dispersancy of solid particles and the protection of metallic surfaces from corrosion. This leads to the most varied fields of use of Aminoalkylenphosphonsäuren and their salts, such as in washing and cleaning processes and as a chelating agent in the stabilization of peroxide but also as an additive for the production and treatment of drinking water, industrial industrial water and oil field water treatment.

When used as an additive for detergents and cleaners for domestic, institutional and industrial applications, aminoalkylenephosphonic acids function as multifunctional additives. In household detergent formulations, they not only undertake the complexation of unwanted heavy metal ions to ensure the stability of bleach-active components, but also inhibit or retard the formation of lime and other sparingly soluble alkaline earth compounds and thus prevent the deposition of these substances on machine parts and textile fabric. In addition, they help wash out bleachable stains without bleach ( Henning, K .: Developments in Liquid Detergents and Detergent Additives, SÖFW Journal 132 (2006), H.6, 61-67. )

For various industrial applications, however, developments have prevailed that have products in the form of aqueous systems as the final target of the application, but in which the raw material formulations are used in an as anhydrous form as possible.

These objects are achieved, on the one hand, in that solids are combined with one another as formulation components or, on the other hand, solids are dissolved or dispersed in a nonaqueous solvent or solvent system. On the one hand to provide the necessary level of active ingredients and on the other hand to protect the formulation from external influences such as high humidity, so as to guarantee the storage stability and usability over long periods, the products are optionally packed in portions. This also offers the consumer the elegant possibility of exact dosage of the detergent formulation, so that dosing errors are avoided.

However, since water serves as the reaction medium for the preparation of aminoalkylenephosphonic acids, aminoalkylenephosphonic acids are for the most part marketed as aqueous solutions as a result of the preparation. For special applications, such as for example in pulverulent, lumpy or pasty formulations, special aminoalkylenephosphonic acids or hydroxybisphosphonic acids are converted out of the aqueous solutions into their solid form via additional process steps.

Nonaqueous solutions of aminoalkylenephosphonic acids and especially their alkali salts in solvents other than water but which are completely soluble in water are currently unknown.

US 3,770,815 discloses, for example, oil-soluble phosphonic acid formulations, wherein exclusively phosphorous acid is used as aminotris (methylenephosphonic acid) in combination with long-chain 1,3-diaminoalkanes in which the alkyl radical of the 1,3-diaminoalkanes has at least 10 carbon atoms and as solvent mixtures of water-immiscible alcohols, such as Example octanol, with water-miscible toxic alcohols, such as methanol, are used. The disclosed mixtures contain water of the order of at least 50% up to 200% of the amount of aminotrismethylenephosphonic acid used.

In the course of the promotion of the improvement of the sustainability in the recipe composition and aspects of the preventive protection against unintentional contact of persons with the liquid detergent formulations set for few years highly concentrated formulations (so-called "super concentrates") in the form of so-called "unit dose packagings", which the necessary amount of the liquid detergent in a water-soluble film (for example. Based on polyvinyl alcohol homo- or copolymers) pre-dosed, a new standard (cf. EP 1 516 917 A1 ). This new form of administration makes it possible to precisely dose formulations according to the requirements of the degree of contamination, so that overdoses and thus unnecessary burden on the environment are avoided and packaging material and transport costs are saved to a significant amount. However, this new technology requires the use of highly concentrated surfactants in order to achieve the water content of the final formulation in as optimal an area as possible, ie by 8% by mass (cf., for example, US Pat. WO 2013/074589 A1 ) and thus to prevent the premature opening or release of the water-soluble packaging film.

For additives of powerful liquid detergent formulations, e.g. Polymers, enzymes and aminoalkylenephosphonic acids which are particularly useful in liquid detergents because of their performance properties, but whose dosage forms are limited to solutions with a relatively high water content (ie> 40%), therefore reduce the possible amounts and possible uses, in particular taking into account the total water content the final recipe, which can lead to losses in general washing performance.

Also, scale control applications in petroleum and natural gas offshore production, such as the combined dosing of thermodynamic hydrate inhibitors, such as methanol or glycol derivatives, and phosphonic acid scale inhibitors, have some serious compatibility problems with known scaling inhibitors Aminoalkylenphosphonsäuren which are characterized by immiscibility, turbidity or precipitation. This often makes independent installations necessary for metering the various components and causes high costs.

There is therefore a keen interest and a great need for aminoalkylenephosphonic acids and their derived formulations which contain the aminoalkylenephosphonic acids in concentrated form and can be commercialized as non-aqueous solutions, thus providing the formulator with an alternative to conventional dosage forms in the respective fields of application and to remove the limitations imposed by the aqueous delivery form.

It is therefore an object of the present invention to provide homogeneous, concentrated solutions of aminoalkylenephosphonic acids in non-aqueous solvents.

• a) eine Aminoalkylenphosphonsäure oder deren korrespondierendes Alkalisalz, mit einem Gehalt im Bereich von 5 bis 35 Ma.-%,
• b) einen mehrwertige Alkohole, aufweisend ein C₂- bis C₆-Kohlenstoffgerüst,
• c) einen Löslichkeitsvermittler, wobei, das Massenverhältnis von mehrwertigem Alkohol zu Löslichkeitsvermittler im Bereich von 40:1 bis 2:1 liegt.

According to the invention, the object is achieved by providing a homogeneous liquid formulation of aminoalkylenephosphonic acids or their alkali metal salts in an organic system, at least containing the components:

• a) an aminoalkylenephosphonic acid or its corresponding alkali metal salt, having a content in the range from 5 to 35% by mass,
• b) a polyhydric alcohol having a C ₂ to C ₆ carbon skeleton,
• c) a solubilizer, wherein the mass ratio of polyhydric alcohol to solubilizer is in the range of 40: 1 to 2: 1.

Surprisingly, it has now been found that highly concentrated nonaqueous solutions comprising at least one aminoalkylenephosphonic acid can be prepared using polyhydric alcohols and small amounts of a solubilizer. This is all the more surprising since the aminoalkylenephosphonic acids are strongly polar substances which have a multiplicity of ionization possibilities (in particular phosphonic acid groups and amino groups) and are thus poorly soluble per se in nonaqueous, relatively nonpolar solvents. With the aid of this anhydrous liquid formulation according to the invention, containing aminoalkylenephosphonic acids and their alkali metal salts, the final formulator has the possibility of introducing a larger amount of the desired aminoalkylenephosphonic acids into the formulation of a product. This gives the formulator new options to be able to optimally adjust the water content of a product according to the respective needs and to use other components (such as enzymes) in concentrations previously impossible due to the total water content of all aqueous formulation ingredients.

Advantageously, the liquid formulation according to the invention is a nonaqueous solution in which the at least one aminoalkylenephosphonic acid is highly concentrated. Particularly advantageous for the particular application is the remaining amount of water in the liquid formulation according to the invention below a concentration limit, which would have adverse effects on the respective application. The resulting advantages are, on the one hand, a higher concentration of washing-active additives, such as, for example, anionic and nonionic surfactants, and an increased service life of hydrolysis Enzymes such as proteases, on the other hand, are associated with savings in many ways (for example, in transportation costs and packaging materials such as bottles and cartons).

Further advantageously, the highly polar aminoalkylenephosphonic acids are homogeneously dissolved in a nonaqueous liquid formulation, i. all components of the liquid formulation according to the invention are uniformly distributed (mixed) before.

It is furthermore advantageous that the solvents used for the solution are non-toxic and can be or are produced on the basis of renewable raw materials. Another advantage is the unlimited water solubility of the non-aqueous formulation, which completely guarantees the functionality of the aminoalkylenephosphonic acids used.

For the purposes of the invention, the term aminoalkylenephosphonic acid is understood as meaning both the free acids and their corresponding alkali metal salts, with aminoalkylenephosphonic acids in particular represented by the structural element N-CH ₂ -P (O) (OX) ₂ (X = H or M, where M is a) Metal cation, preferably an alkali metal ion, in particular M = Na, K) are characterized and have on the nitrogen atom both further methylene phosphonic acid fragments and / or alkyl, aryl, alkylamino, hydroxyalkyl substituents.

As corresponding alkali salts of the aminoalkylenephosphonic acid (as defined above) are defined as ionic compounds of an aminoalkylenephosphonic acid and an alkali metal ion (eg., Lithium, sodium, potassium, rubidium) understood in which the deprotonated form of Aminoalkylenphosphonsäure and the alkali metal ions in a stoichiometric ratio in the range 1: 1 to 1:10.

Alkali salts of the aminoalkylenephosphonic acids are preferably the respective sodium and potassium salts. The stoichiometric ratio of the alkali metal ions to the aminoalkylenephosphonic acid is preferably in the range from 1: 1 to 5: 1.

The aminoalkylenephosphonic acid is preferably present in the liquid formulation according to the invention in a concentration in the range from 5 to 35% by mass, particularly preferably 10 to 30% by mass, very particularly preferably 15 to 25% by mass.

The data in percent by mass (% by mass) are derived from the mass fraction w of the respective constituent in the (aqueous) solution and are found to be one hundred times this value (m% = 100 · w). The mass fraction of the respective component is determined as a proportion of the mass of this component in the mass of the total solution after mixing, ie the masses of all dissolved in the solvent components plus the mass of the solvent itself.

The mass fraction of a component (e.g., an aminoalkylenephosphonic acid) in solution can be determined in a variety of ways known to those skilled in the art, for example, by gravimetric methods, by complexometric titration, or by acid-base titration.

In a preferred embodiment of the liquid formulation according to the invention, the at least one aminoalkylenephosphonic acid of the aqueous crude product is selected from amino-tris (methylenephosphonic acid) (ATMP), ethylenediamine-tetra (methylenephosphonic acid) (EDTMP), diethylenetriamine-penta (methylenephosphonic acid) (DTPMP), triethylenetetramine hexa (methylenephosphonic acid) (TETHMP), hydroxyethylamino-di (methylenephosphonic acid) (HEMPA), bis (hexamethylenetriaminepenta (methylenephosphonic acid)) (BHMTMP) and / or hexamethylenediamine-tetra (methylenephosphonic acid) (HDTMP).

For the purposes of the present invention, a solvent is understood as meaning a liquid carrier which is capable of completely absorbing the substance to be dissolved, so that, if appropriate by addition of further components (such as solubilizers), a homogeneous, clear solution results.

Preferably, the solvent of the liquid formulation of the invention is a polyhydric alcohol having a C ₂ to C ₆ carbon skeleton and at least two hydroxy groups. Particularly suitable polyhydric alcohols for preparing a homogeneous solution of aminoalkylenephosphonic acids or their alkali metal salts in the liquid formulation are 1,2-ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, glycerol, polyethylene glycol and mixtures thereof. Advantageously, mixtures of different solvents in the liquid formulation according to the invention can be used to adjust the desired viscosity of the liquid formulation.

The liquid formulation according to the invention preferably contains polyhydric alcohols with a total content in the range from 30 to 90% by weight, particularly preferably in the range from 40 to 85% by weight.

For the purposes of the invention, a solubilizer is understood as meaning a substance which has at least one, preferably two or more than two (eg 3, 4, 5, 6, etc.) functional groups and which, by virtue of their presence, improves the solubility the poorly soluble substance in the solvent contributes. Examples of solubilizers are so-called hydrotropes, such as, for example, sodium cumene sulphonate or sodium ethylhexyl sulphate, which are advantageous for the solubilization of nonionic surfactants in aqueous solutions. Decisive for a solubility-improving effect are the chemical and physical interactions between the substance to be dissolved (in particular the aminoalkylenephosphonic acid) and the solubilizer on the one hand and the chemical and physical interactions between the solubilizing agent and the solvent on the other hand.

The solubilizer for a liquid formulation according to the invention is preferably selected from the group of amino alcohols. By definition, amino alcohols always have at least one hydroxyl group and at least one primary or secondary or tertiary amino groups. Suitable amino alcohols are straight-chain and branched, aliphatic and cycloaliphatic amino alcohols having generally 2 to 12, preferably 2 to 10, carbon atoms.

The amino alcohol is preferably monoethanolamine, diethanolamine, triethanolamine, 3-aminopropanol, amino-2-propanol or a mixture thereof.

The liquid formulation according to the invention preferably contains the solubilizer with a total content in the range of 0.5 and 30% by weight, more preferably in the range of 1.0 and 25% by weight, very particularly preferably in the range of 1.0 and 20 wt .-%.

For the purposes of the invention, anhydrous means that the entire system in question contains only the amounts of water (equilibrium moisture), either derived from adhering water of hydration from the raw materials used or, if it was assumed that aqueous solutions, under standard conditions (atmospheric pressure) are not separated by distillation or in which the total concentration of water is less than 10% by mass.

The water content (equilibrium moisture) of the liquid formulation according to the invention, measured at 25 ° C., is preferably below 15% by mass, preferably below 10% by mass, particularly preferably below 7.5% by mass.

Provided should not be assumed that the already present in the form of their alkali metal salts aminoalkylenephosphonic acids, but from the free aminoalkylenephosphonic acids, it may be advantageous that aminoalkylene phosphonic acids with an anhydrous base selected from the group of alkali metal hydrogen carbonates (eg. NaHCO ₃₎ and alkali metal (eg. K ₂ CO ₃ ) or a concentrated aqueous alkali selected from the group of alkali metal hydroxides (for example NaOH, KOH).

If desired, drying agents may be added to the liquid formulation according to the invention after complete dissolution of the constituents in order to bind contained water. Anhydrous alkali metal sulfates or alkaline earth sulfates, such as, for example, sodium sulfate or magnesium sulfate, are preferably used for this purpose.

If desired, the liquid formulation according to the invention may contain, in addition to the abovementioned components, further additives such as emulsifiers, polymers (for example water-soluble salts of polycarboxylate polymers and mixed copolymers according to US Pat DE 1 467 656 ), Fillers, surfactants, pigments, dyes, enzymes and / or substances for adjusting the pH, be added.

Surfactants useful in principle are well known to the person skilled in the art and are selected from the group consisting of anionic, cationic, nonionic and amphoteric surfactants, polymeric surfactants and surfactants with heteroatoms being included in the hydrophobic group.

Enzymes have been used as cleaning additives for many years and are therefore well known to those skilled in the art. For example. were used in 1932 enzymes in soap preparations, which had a greatly improved cleaning action ( US 1,882,279 ).

According to a preferred embodiment of the present invention, low molecular weight mono- and / or dialcohols may also be added to the liquid formulation. Preferred low molecular weight monoalcohols according to the invention have a C ₁ to C ₄ -carbon skeleton and a hydroxyl group bonded to a primary or secondary carbon atom and are preferably selected from methanol, ethanol, isopropanol and n-propanol. For the purposes of the invention, low molecular weight dialcohol is to be understood as meaning an alcohol having two terminal hydroxyl groups which has 2 to 10 carbon atoms and optionally has 1 to 3 oxyethylene groups (-O-CH ₂ CH ₂ -) in the molecule. Preferably, the low molecular weight dialcohol is selected from monoethylene glycol, propane-1,3-diol, diethylene glycol, triethylene glycol and tetraethylene glycol.

Usually, the aminoalkylenephosphonic acid is first dissolved or homogeneously dispersed in dissolved or solid form in the polyhydric alcohol, and the mixture is then intensively mixed with the solubilizer to be used by adding the solubilizer. It can be provided that the mixture containing the aminoalkylenephosphonic acid in the polyhydric alcohol is neutralized by addition of a base before the addition of the solubilizer takes place.

Alternatively, however, it can also be provided that the aminoalkylenephosphonic acid in dissolved or solid form is first mixed with the solubilizer to be used and the mixture is subsequently mixed with the polyhydric alcohol with constant stirring and / or shaking.

• a) Vorlegen mindestens einer Aminoalkylenphosphonsäure, vorzugsweise in gelöster oder fester Form,
• b) Zugabe einer Menge des mehrwertigen Alkohols zu der Aminoalkylenphosphonsäure in einem Massenverhältnis von 1:1 bis 15:1, so dass eine bewegliche heterogene oder homogene Mischung vorliegt,
• c) Zugabe einer Menge des Lösungsvermittlers zu der Mischung aus b) in einem Massenverhältnis 1:3 bis 1:60, so dass eine homogene Lösung erhalten wird.

A further subject of the present invention is therefore also a process for the preparation of the liquid formulation according to the invention comprising the steps:

• a) presentation of at least one aminoalkylenephosphonic acid, preferably in dissolved or solid form,
• b) adding a quantity of the polyhydric alcohol to the aminoalkylenephosphonic acid in a mass ratio of 1: 1 to 15: 1, so that a mobile heterogeneous or homogeneous mixture is present,
• c) adding an amount of the solubilizer to the mixture of b) in a mass ratio of 1: 3 to 1:60, so that a homogeneous solution is obtained.

Preferably, the mixture, at least containing the aminoalkylenephosphonic acid and the polyhydric alcohol, during the process according to the invention has a temperature in the range from 0 to 85 ° C, more preferably from 15 to 80 ° C, most preferably from 25 to 80 ° C.

As the aminoalkylenephosphonic acid in solid form, the free acids are preferably used here, which can be isolated by various processes, both in the laboratory and industrially. Preferably, the aminoalkylenephosphonic acid in solid form contains at least one aminoalkylenephosphonic acid with a total content in the range of 50 and 100% by mass, particularly preferably 60 and 100% by mass, very particularly preferably 80 and 100% by mass.

Preferably, the aminoalkylenephosphonic acid in dissolved form contains at least one aminoalkylenephosphonic acid with a total content in the range of 10 and 65% by weight, more preferably 15 and 65% by weight, most preferably in the range of 20 and 60% by weight.

An aminoalkylenephosphonic acid in dissolved form can be suitably preferably analogously to the work of Moedritzer and Irani ( J. Org. Chem. 1966, 31, 1603-1607 ) provide. In this case, in the presence of a strong acid (eg hydrochloric acid (HCl), sulfuric acid) preferably primary amines (eg ammonia, aminoethane, 1,2-diaminoethane, aminoethanol, etc.), phosphorous acid (H ₃ PO ₃ ) and formaldehyde, taking into account the converted as complete as possible conversion of all NH functionalities necessary stoichiometric ratios to Aminoalkylenphosphonsäuren. As an alternative to the use of H ₃ PO ₃ and HCl, it is also possible to work with phosphorus trichloride and water. In a phosphonomethylation thus carried out, the fully substituted aminoalkylenephosphonic acid as the main product is usually obtained with a purity of 75-85 wt%.

Alternatively, an aqueous crude product containing DTPMP can also be obtained, for example, via a nucleophilic substitution reaction based on a Michaelis-Arbuzov reaction (reports 1898, 31, 1048) followed by acid hydrolysis.

Commercially available aqueous solutions containing at least one aminoalkylenephosphonic acid with a total content of between 20 and 60% by weight, which are for example listed under the trade names such as, for example, in the form of aminoalkylsulfonic acids, may also be used as the aminoalkylenephosphonic acids in dissolved form. B. Cublen ^® AP 1, Cublen ^® AP5, Cublen ^® E3115, Cublen DNC 450 Cublen ^® R60, Cublen BTP 470 Cublen ^® D5113 Zschimmer & Schwarz marketed the company..

Alternatively, preferably, the aminoalkylenephosphonic acid may be provided in dissolved form by dissolving and / or suspending a solid containing an aminoalkylenephosphonic acid in water or a water-containing solution. Preferably, the solid is dissolved and / or suspended by heating to a temperature of more than 30 ° C, more preferably to a temperature between 30 and 100 ° C, most preferably between 35 and 70 ° C in one or more aqueous solvents. Also preferred is the addition of a stoichiometric amount of an alkali metal base in the dissolution step to increase water solubility.

If it is not intended to start from the aminoalkylenephosphonic acids already present in the form of their alkali metal salts, but from the free aminoalkylenephosphonic acids, it may be advantageous to neutralize the aminoalkylenephosphonic acids with an anhydrous base.

According to a preferred embodiment of the process according to the invention therefore takes place after the presentation of Aminoalkylenphosphonsäure, in particular the free Aminoalkylenphosphonsäuren, in step a) the addition of a base to neutralize the Aminoalkylenphosphonsäure in a stoichiometric ratio of base to Aminoalkylenphosphonsäure from 1: 1 to 5: 1. The base is preferably selected from the group of alkali metal hydrogencarbonates (for example NaHCO ₃ ) and alkali metal carbonates (for example K ₂ CO ₃ ) or a concentrated aqueous alkali selected from the group of alkali metal hydroxides (for example NaOH, KOH).

Optionally, after the preparation of the liquid formulation, the removal of excess amounts of water to a water content in the liquid formulation below 15 wt .-%, preferably below 10 wt .-%, particularly preferably below 7.5 Ma .-% ,

The removal of the excess amount of water preferably takes place by distillation under normal pressure or reduced pressure, so that a homogeneous liquid formulation of the aminoalkylenephosphonic acid according to the invention is obtained.

Alternatively preferably, the removal of the excess amount of water by addition of an inert desiccant, preferably in solid form (eg. Powder or granules), wherein the desiccant binds the water and sets a defined water content in the liquid formulation. The desiccants used are preferably silica gel, zeolites or molecular sieve but also conventional desiccants such as anhydrous calcium sulfate, anhydrous sodium sulfate, anhydrous calcium chloride, anhydrous magnesium sulfate and combinations thereof.

Preferably, the desiccant is added to the liquid formulation to remove the excess amount of water at a level of from 5 to 75 wt%, more preferably 10 to 50 wt%, most preferably 15 to 40 wt%.

After binding of the water to the desiccant, the separation of the teat composition from the liquid formulation according to the invention is carried out by methods known to the person skilled in the art. Preferably, the separation of the desiccant is accomplished by sedimentation (e.g., by centrifugation) and / or by filtration (e.g., with a Buchner funnel).

The liquid formulation according to the invention can also be used inter alia for the preparation of liquid detergent and cleaning agent formulations known per se.

This mode of use of the liquid formulation according to the invention is particularly advantageous where liquid detergent and cleaner formulations are provided as a pre-dosed formulation, preferably in water-soluble packaging materials (eg polyvinyl alcohol films) which dissolves during use thereby releasing the components ,

For the consumer, an exact dosage of the detergent formulation is desirable to avoid dosing errors. The avoidance of overdoses also reduces the inputs of the chemical components contained in detergent formulations into the environment. These objectives are addressed by means of so-called "unit dose packagings", wherein in the case of liquid or gel-like highly concentrated detergent formulations, water-soluble film of polyvinyl alcohol is used for this purpose.

Surprisingly, it has now been found that the liquid formulation according to the invention can be used to prepare homogeneous solutions of the aminoalkylenephosphonic acids in low molecular weight mono- and / or dihydric alcohols.

The task of the aminoalkylenephosphonic acids is to prevent or delay the formation of sparingly soluble alkaline earth salts, such as calcium carbonate or barium sulphate, under the particular conditions of use of these solutions and to increase the unrestricted mobility of these solids in the liquid carrier by disrupting the ordered crystal structure of these alkaline earth compounds ensure (so-called scaling inhibition).

The invention also provides the use of the liquid formulation according to the invention for the preparation of homogeneous solutions of Aminoalkylenphosphonsäuren in low molecular weight alcohols, as they are used, for example, in the oil and gas extraction as gas hydrate inhibitors.

It is known that in media containing gas molecules such as CO ₂ or hydrocarbons, for example C ₁ to C ₄ alkanes and water, gas hydrates, also referred to as clathrate hydrates, can form under certain conditions. These gas hydrates consist of the named gas molecules, which are surrounded by a "cage" of water molecules. Such gas hydrates also occur in water-containing petroleum or natural gas mixtures and can thus, for example, their promotion and during transport lead to blockage of the pipe systems (eg. Pipelines).

To prevent this, gas hydrate inhibitors are added to petroleum or natural gas mixtures, distinguishing between thermodynamic hydrate inhibitors (THI) and kinetic hydrate inhibitors (KHI). Thermodynamic gas hydrate inhibitors act on the equilibrium position of the gas hydrate and shift its formation range to lower temperatures and higher pressures, while kinetic hydrate inhibitors interfere with and delay the formation process (ie, crystallization). Alcohols, glycols and selected alkali metal salts have proven to be particularly effective thermodynamic hydrate inhibitors. Particularly frequently and in large quantities are methanol and monoethylene glycol, but also diethylene glycol and triethylene glycol ( MA Kelland "Production Chemicals for the Oil and Gas Industry, CRC Press, 2009 ), the choice of hydrate inhibitor being determined by local conditions and its commercial availability. TIHs are preferred over KHIs because they offer a facile way to recover the inhibitor, the chemicals are readily available, and they have wide applicability to different gases or gas compositions.

The use of the liquid formulation of the present invention in a thermodynamic gas hydrate inhibitor is particularly advantageous where thermodynamic gas hydrate inhibitors and effective scaling inhibitors need to be dosed to prevent the blockage (obstruction) of piping by gas hydrates, i. For example, solid methane-water agglomerates and sparingly soluble alkaline earth salts, such as barium sulfate to prevent.

Advantageously, the liquid formulation according to the invention offers the formulator of oil field chemicals and operators of the conveyor the possibility of effective exploitation of oil and natural gas deposits, since both components can be dosed due to their miscibility via a line system and thus costly and complex separate supply lines are avoided via independent lines ,

• a) die erfindungsgemäße flüssige Formulierung und
• b) einen niedermolekularen Mono- und/oder Dialkohol, aufweisend 1 bis 10 Kohlenstoffatome,

wobei das Massenverhältnis von flüssiger Formulierung zum niedermolekularen Monound/oder Dialkohol im Bereich von 99:1 bis 1:99 liegt.According to a preferred embodiment of the invention, the thermodynamic gas hydrate inhibitor contains at least:

• a) the liquid formulation according to the invention and
• b) a low molecular weight mono- and / or dihydric alcohol having 1 to 10 carbon atoms,

wherein the mass ratio of liquid formulation to low molecular weight mono- and / or dialcohol is in the range of 99: 1 to 1:99.

It should be noted that the liquid formulation according to the invention and the short-chain alcohol are basically miscible with each other in any mass ratio. However, a mass ratio in which the short-chain alcohol is used in significant excess over the liquid formulation according to the invention is relevant to practice. In the thermodynamic hydrate inhibitor, the short-chain alcohol is preferably present in excess over the liquid formulation according to the invention with a mass ratio of 60:40 to 99: 1, particularly preferably in the range from 90:10 to 99: 1.

The low molecular weight monoalcohol preferably has an optionally branched carbon skeleton containing 1 to 4 carbon atoms and one hydroxyl group. The low molecular weight monoalcohol is particularly preferably selected from methanol, ethanol, isopropanol and n-propanol.

For the purposes of the invention, low molecular weight dialcohol is to be understood as meaning an alcohol having two terminal hydroxyl groups which has 1 to 10 carbon atoms and optionally has 1 to 3 oxyethylene groups (-O-CH ₂ CH ₂ -) in the molecule. Preferably, the low molecular weight dialcohol is selected from monoethylene glycol, propane-1,3-diol, diethylene glycol, triethylene glycol and tetraethylene glycol.

The liquid formulation of the present invention may also be used in combination with other suitable components for use as a scaling inhibitor in a gas hydrate inhibitor. These other components may also be water-soluble salts, in particular alkali metal halides or alkali metal formates.

It is understood that the examples of the invention mentioned above and those yet to be explained can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the invention.

The features of the invention disclosed in the specification and the claims may be of importance both individually and in any combination for the realization of the invention in its various embodiments.

Further features and advantages of the invention will become apparent from the following embodiments, without limiting the invention to these.

Example 1:

8.4 g of a purified, solid DTPMP containing 68% by mass (remainder: water of hydration) are weighed into 40.0 g of 1,2-propylene glycol in a screwed glass and dispersed therein by shaking. Then 2.5 g of anhydrous sodium bicarbonate are added, shaken again and finally add 1.2 g of monoethanolamine. The screw-cap is loosely capped so that carbon dioxide formed can escape and shaken on a temperature-controlled laboratory shaker at 50 ° C for 24 hours. After initial evolution of gas (carbon dioxide), a homogeneous yellow solution of the sodium salt of DTPMP is obtained with a DTPMP concentration of 11.2% by mass (determined by complexometric titration) and a water content of 7.5% by mass and a sodium Ion concentration of 1.35% (determined by ion chromatography). The final proportions of monoethanolamine and 1,2-propylene glycol are 2.3% by mass and 77.9% by mass, respectively.

Example 2:

In a screwed glass, 6.2 g of a purified and dried DTPMP containing 93% by mass (balance: water of hydration) is weighed into 16.7 g of 1,2-propylene glycol and dispersed therein by shaking. Subsequently, 2.5 g of anhydrous sodium bicarbonate are added to neutralize the aminoalkylenephosphonic acid, shaken again and finally add 1.8 g of monoethanolamine. The screw-cap is loosely capped so that carbon dioxide formed can escape and shaken on a temperature-controlled laboratory shaker at 50 ° C for 24 hours. After initial evolution of gas (carbon dioxide) gives a homogeneous yellow solution of the sodium salt of DTPMP with a DTPMP concentration of 21.2% by mass (determined by complexometric titration) and a water content of 3.2% by mass and a Na ion concentration of 2.54 mass% (determined by ion chromatography). Monoethanolamine and 1,2-propylene glycol are included in the final formulation at 4.9% by mass and 66.0% by mass, respectively.

Example 3:

In a screwed glass, 6.2 g of a purified and dried DTPMP containing 93% by mass (balance: water of hydration) is weighed into 16.5 g of 1,2-propylene glycol and dispersed therein by shaking. Subsequently, 2.4 g of a commercial 50% sodium hydroxide solution and 1.2 g of monoethanolamine are added. The screw-cap is shaken tightly closed on a temperature-controlled laboratory shaker at 60 ° C for 12 hours. This gives a homogeneous pale yellow solution of the sodium salt of DTPMP with a DTPMP concentration of 21.9% by mass (determined by complexometric titration) and a water content of 8.2% by mass and a Na ion concentration of 2.55 Ma .-% determined by ion chromatography (theoretically 2.50 mass%). The proportion of the solvent 1,2-propylene glycol in the final formulation is 62.7% by mass, that of the solubilizer monoethanolamine is 4.6% by mass.

Example 4:

In a screwed glass 4.5 g of a purified and dried EDTMP containing 95 wt .-% (balance: water of hydration) are weighed into 30.0 g of 1,2-propylene glycol and dispersed therein by shaking. Subsequently, 1.4 g of anhydrous potassium carbonate and 3.7 g of monoethanolamine are added. To allow evolved carbon dioxide to escape, the screw-cap is only slightly closed and shaken on a temperature-controlled laboratory shaker at 60 ° C for 24 hours. This gives a homogeneous pale yellow solution of the cleavage salt of EDTMP with a concentration of 12.9 wt .-% (determined by complexometric titration, calculated as the dipotassium salt of EDTMP) and a water content of 1.0 wt .-%. The concentration of the 1,2-propylene glycol in the final formulation is 76.6% by mass, that of monoethanolamine is 9.5% by mass.

Example 5:

In a screw jar, 3.0 g of a crystalline ATMP containing 99% by mass (balance: water of hydration) are weighed into 30.0 g of glycerol and dispersed therein by shaking. Subsequently, 1.7 g of anhydrous sodium bicarbonate are added for neutralization and solubilized with 2.4 g of monoethanolamine. To allow evolved carbon dioxide to escape, the screw-cap is only slightly closed and shaken on a temperature-controlled laboratory shaker at 60 ° C for 24 hours. This gives a homogeneous, almost colorless, viscous solution of the sodium salt of ATMP with an ATMP concentration of 8.3 mass% (determined by complexometric titration), a water content of 1.1 mass%, a content of glycerol of 82 , 9 Ma .-% and a content of monoethanolamine of 6.6 Ma .-%.

Example 6:

In a screwed glass, 10.9 g of a crystalline EDTMP containing 95% by mass (balance: water of hydration) are weighed into 25.0 g of 1,2-propylene glycol and dispersed therein by shaking. Subsequently, 9.4 g of anhydrous 3-aminopropanol are added and shaken on a temperature-controlled laboratory shaker at 60 ° C for 24 hours. This gives a homogeneous yellow solution having an EDTMP concentration of 22.9% by mass (determined by complexometric titration, calculated as EDTMP) and a water content of 1.2% by mass. The proportions of 1,2-propylene glycol and 3-aminopropanol in the final formulation are 55.2% by mass and 20.7% by mass, respectively.

Example 7:

10.5 g of a purified crystalline DTPMP containing 68% by mass (balance: water of hydration) are weighed into 19.0 g of 1,2-propylene glycol in a screwed glass and dispersed therein by shaking. Subsequently, 5.6 g of amino-2-propanol are added and shaken on a temperature-controlled laboratory shaker at 50 ° C for 24 hours. This gives a homogeneous yellow solution with a DTPMP concentration of 20.3% by mass (determined by complexometric titration), a proportion of 1,2-propylene glycol of 54.1% by mass and a water content of 9.1 Ma. % and a concentration of amino-2-propanol of 16.0% by mass.

Example 8:

In a 500 ml round bottom flask, 100 g of commercially available Cublen D 5113 (sodium salt of DTPMP) are mixed with 14.6 g of monoethanolamine and, after homogenization, immediately mixed with 132.4 g of glycerol. This gives a clear, light brown solution. On a rotary evaporator are then at a bath temperature distilled off from 60 ° C and a pressure of 100 mbar 42.0 g of water. The resulting viscous solution is clear and contains the sodium salt of DTPMP at a concentration of 20.7 mass% (calculated as DTPMP acid) and has a water content of 2.1 mass%. The proportion of glycerol in the mixture is 64.6% by mass. The resulting concentration of monoethanolamine is 7.1% by mass. Sodium chloride is included in the mixture at a concentration of 1.8% by mass.

Example 9:

In a 500 ml round bottom flask, 100 g of commercially available Cublen D 5113 (sodium salt of DTPMP) are mixed with 70.3 g of 1,2-propylene glycol and 14.6 g of monoethanolamine and thoroughly homogenized. A clear, light-brown solution is obtained from which 39.3 g of water are distilled off using a rotary evaporator at a bath temperature of 60 ° C. and a pressure of 100 mbar. The resulting viscous solution is clear and has a DTPMP content of 29.3 mass% and a water content of 5.7 mass%. The solution further contains 2.3% by mass of sodium chloride, 10.0% by mass of monoethanolamine and 48.3% by mass of 1,2-propylene glycol.

Example 10:

In a glass jar, 5.0 g of a purified and dried HDTMP containing 99% by mass (balance: water of hydration) is weighed into 30.0 g of glycerol and dispersed therein by shaking. Subsequently, 1.7 g of anhydrous sodium bicarbonate and 1.8 g of monoethanolamine are added. The screwed glass is closed to such an extent that the resulting carbon dioxide can escape and shaken on a temperature-controlled laboratory shaker at 60 ° C for 24 hours. A homogeneous light yellow solution of the sodium salt of HDTMP is obtained with an HDTMP concentration of 13.2% by mass (determined by complexometric titration) and a water content of 1.1% by mass. The proportion of the solvent 1,2-propylene glycol in the final formulation is 79.9% by mass, that of the solubilizer monoethanolamine is 4.8% by mass.

Example 11:

In a 500 ml round bottom flask, 120.2 g of commercially available Cublen R 50 (about 50% aqueous solution of Hydroxyethylaminobis (methylenephosphonic acid), HEMPA) are slowly mixed with 38.3 g of a commercial 50% sodium hydroxide solution. 29.3 g of monoethanolamine and 83.6 g of 1,2-propylene glycol are then added to the resulting solution of the sodium salt of phosphonic acid and thoroughly homogenized. The resulting mixture is transferred to a 500 ml one-necked round bottom flask and the water is distilled off largely on a rotary evaporator. This gives a clear, pale yellow solution with the following final concentrations: 28.2% by mass of sodium salt of HEMPA, 14.7% by weight of monoethanolamine, 41.9% by mass of 1,2-propylene glycol, 2.9% by mass of sodium chloride and 12.3% by mass of water.

Example 12:

In a 500 ml round bottom flask, 94.5 g of a purified crystalline DTPMP containing 80% by mass (balance: water of hydration) are dispersed in 94.5 g of water and neutralized by adding 21.8 g of 50% NaOH, whereby a clear solution arises. Subsequently, 39.2 g of monoethanolamine and 192.8 g of 1,2-propylene glycol are added successively with stirring, and the resulting mixture is homogenized. 117.8 g of distillate are subsequently removed from the mixture obtained. A clear, pale yellow solution is obtained with the following final concentrations: 26.3% by mass disodium salt of DTPMP (corresponding to 24.4% by mass DTPMP), 3.5% by mass water, 12.0% by mass monoethanolamine and 58% 2% by mass of 1,2-propylene glycol.

Example 13:

In a 500 ml round bottom flask, 94.5 g of a purified crystalline DTPMP containing 80% by mass (balance: water of hydration) are dispersed in 94.5 g of water and neutralized by adding 21.8 g of 50% NaOH, whereby a clear solution arises. Subsequently, 39.2 g of monoethanolamine and 179.5 g of glycerol are added in succession while stirring, and the resulting mixture is homogenized. From the mixture obtained, 104.6 g of distillate are subsequently removed. A clear, pale yellow solution is obtained with the following final concentrations: 24.8 M% disodium salt of DTPMP (corresponding to 23.0 M% DTPMP), 8.2 M% water, 12.0 M% monoethanolamine and 55, 0% by weight of glycerol.

Example 14:

Compatibility test of the formulations of the invention with low molecular weight mono- and dialcohols

The formulations of Examples 12 and 13 are mixed in different mass ratios with the indicated alcohol and the appearance of the resulting mixtures visually evaluated. For comparison with the formulations according to the invention, the commercial product CUBLEN D 3217N is tested at a concentration of likewise 25% by mass DTPMP under identical experimental conditions. Aminoalkylenephosphonic product alcohol mixing ratio Appearance 1 Cublen D 3217N MeOH 1:99 cloudy Formulation from Ex. 12 MeOH 1:99 clear, Formulation from Ex. 13 MeOH 1:99 clear, 2 Cublen D 3217N MeOH 10:90 cloudy with sediment Formulation from Ex. 12 MeOH 10:90 clear, Formulation from Ex. 13 MeOH 10:90 clear, 3 Cublen D 3217N MeOH 50:50 Two-phase system Formulation from Ex. 12 MeOH 50:50 clear, Formulation from Ex. 13 MeOH 50:50 clear 4 Cublen D 3217N MeOH 90:10 clear Formulation from Ex. 12 MeOH 90:10 clear Formulation from Ex. 13 MeOH 90:10 clear 5 Cublen D 3217N MeOH 99: 1 clear Formulation from Ex. 12 MeOH 99: 1 clear Formulation from Ex. 13 MeOH 99: 1 clear 6 Cublen D 3217N DEG 10:90 Clear Formulation from Ex. 12 DEG 10:90 Clear Formulation from Ex. 13 DEG 10:90 Clear 7 Cublen D 3217N DEG 50:50 Two-phase system Formulation from Ex. 13 DEG 50:50 Clear Formulation from Ex. 13 DEG 50:50 clear

The results of the experiments clearly demonstrate that mixtures with low molecular weight mono- and dialcohols in any ratio are possible with the formulations according to the invention without impairing the homogeneity and stability of these solutions, while commercial products can not be used over the entire mixing range.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 3770815 [0008]
• EP 1516917 A1 [0009]
• WO 2013/074589 A1 [0009]
• DE 1467656 [0037]
• US 1882279 [0039]

Cited non-patent literature

• Henning, K .: Developments in Liquid Detergents and Detergent Additives, SÖFW Journal 132 (2006), H.6, 61-67. [0003]
• J. Org. Chem. 1966, 31, 1603-1607 [0047]
• MA Kelland "Production Chemicals for the Oil and Gas Industry, CRC Press, 2009 [0065]

Claims (12)

Homogeneous liquid formulation of aminoalkylenephosphonic acids or their alkali metal salts in an organic system, at least comprising: a. an aminoalkylenephosphonic acid or its alkali metal salt with a content in the range from 5 to 35% by mass, b. a polyhydric alcohol having a C ₂ to C ₆ carbon skeleton, c. a solubilizer wherein the weight ratio of polyhydric alcohol to solubilizer ranges from 40: 1 to 2: 1. A liquid formulation according to claim 1, characterized in that the aminoalkylenephosphonic acid in the organic formulation is selected from ATMP, EDTMP, DTPMP, TETHMP, HEMPA, BHMTP and HDTMP. A liquid formulation according to claim 1 to 2, characterized in that the aminoalkylenephosphonic acid is selected in the form of the sodium salts and potassium salts. Liquid formulation according to claim 1 or 3, characterized in that the solubilizing agent is selected from the group of amino alcohols. A liquid formulation according to any one of claims 1 to 4, characterized in that the polyhydric alcohol is selected from 1,2-ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, glycerol and polyethylene glycol. Liquid formulation according to one of claims 3 to 5, characterized in that the amino alcohol is monoethanolamine, diethanolamine, triethanolamine, 3-aminopropanol and / or amino-2-propanol. A process for the preparation of a liquid formulation according to any one of claims 1 to 6, comprising the steps of: a. Preparation of at least one aminoalkylenephosphonic acid, preferably in dissolved or solid form, b. Adding an amount of the polyhydric alcohol to the aminoalkylenephosphonic acid in a mass ratio of from 1: 1 to 15: 1 so that there is a mobile heterogeneous or homogeneous mixture, c. Adding an amount of the solubilizer to the mixture of b) in a mass ratio of 1: 3 to 1:60, so that a homogeneous solution is obtained. A method according to claim 7, characterized in that after the preparation of the liquid formulation, the removal of excess amounts of water to a water content in the liquid formulation is below 15% by mass. A method according to claim 7, characterized in that after the presentation of the Aminoalkylenphosphonsäure in process step a), the addition of a base in a stoichiometric ratio of base to Aminoalkylenphosphonsäure from 1: 1 to 5: 1 takes place. Use of a liquid formulation according to any one of claims 1 to 6 for the preparation of liquid detergent and cleaner formulations. Use of a liquid formulation according to any one of claims 1 to 6 for the preparation of homogeneous solutions of Aminoalkylenphosphonsäuren in low molecular weight alcohols. Thermodynamic gas hydrate inhibitor containing at least: a) the liquid formulation according to the invention and b) a low molecular weight mono- and / or dihydric alcohol having 1 to 10 carbon atoms, wherein, the mass ratio of liquid formulation to low molecular weight mono- and / or dialcohol is in the range of 99: 1 to 1:99.