EP2137279A1

EP2137279A1 - Production and use of paraffin inhibitor formulations

Info

Publication number: EP2137279A1
Application number: EP08736064A
Authority: EP
Inventors: Marcus Guzmann; Yaqian Liu; Rouven Konrad; Diana Franz
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2007-04-13
Filing date: 2008-04-10
Publication date: 2009-12-30
Also published as: US20100130385A1; CA2682144A1; WO2008125588A1; RU2009141773A; CN101668828A

Abstract

The present invention relates to a method for the production of a paraffin inhibitor formulation, comprising the following steps: (a) producing a mixture containing (i) a wax-like paraffin inhibitor component having a melting point of > 0ºC, (ii) an emulsifier component, and (iii) optionally water at a temperature in a first temperature range, wherein the first temperature range is higher than the melting point of the component (i), and wherein the optionally present water produces an w/o emulsion and has a weight proportion that is lower than the sum of the weight proportions of the components (i) and (ii); (b) adding water to the mixture, wherein after the water has been completely added an o/w emulsion is present; (c) cooling the o/w emulsion from step (b) to a temperature in a second temperature range, which is lower than the melting point of the component (i); and (d) optionally adding an organic solvent component (iv), which can be mixed at least partly with water and in which the paraffin inhibitor component is not soluble. The present invention further relates to formulations that can be obtained from a production method, and to the use and application for paraffin inhibitors/solidification point reduction of crude oil or crude oil raffinates.

Description

Preparation and Use of Paraffin Inhibitor Formulations

The present invention relates to paraffin inhibitor formulations, their preparation, use and methods of paraffin inhibition / pour point reduction by such formulations.

In oil production, due to temperature and pressure changes, crystallization of paraffin molecules, which are a component of crude oil and crude oil raffinate, occurs. Due to this crystallization process, these paraffins can accumulate in production wells, production probes, pipelines or plant parts, such as tanks, which can be detrimental to the productivity of the oil extraction and oil storage or transport.

Furthermore, the crystallization of paraffin molecules falls below the so-called pour point to the stagnation of crude oil. The oil can then no longer be transported, with the result that the oil production can come to a standstill.

To prevent such paraffin deposits or oil sticking, paraffin inhibitors or pour point depressants are generally added to the corresponding systems. Typically, the paraffin inhibitors and pour point depressants consist of polymeric structures that are waxy in consistency. Even after mixing the waxy products with organic solvents, the resulting blends are of waxy consistency at low temperatures. This also applies to dilute solutions of paraffin inhibitors or pour point depressants.

These waxy products can be applied in different ways.

One possibility is to melt these waxy products in situ and then meter them as a melt into the crude oil stream or into the oil plant parts. The disadvantage of this method is that expensive equipment for melting and metering must be kept or maintained. In the case of failure of devices for melting, such as a heater, the dosage of the paraffin inhibitor or pour point depressant is no longer possible, which leads to the above problems. Alternatively, the paraffin inhibitors may be dissolved in solvents and then fed to the final product in the form of a solution. Such a procedure is described for example in WO-A 00/32720.

However, the paraffin inhibitors are only soluble in low concentrations or the solution as such has a very high viscosity. This is especially true at low temperatures where the formulated polymers are no longer soluble, i. either fail or the products become stuck.

For countries such as Russia, it is necessary that products even at -50 ⁰ C still be liquid and dosed.

There is therefore a need for suitable formulations containing paraffin inhibitors which at least partially lack the disadvantages described above.

It is therefore an object of the present invention to provide a paraffin inhibitor formulation and processes for its preparation which at least partially obviate the abovementioned disadvantages.

The object is achieved by a method for producing a paraffin inhibitor formulation comprising the steps

(a) producing a mixture containing

(i) a waxy paraffin inhibitor component having a melting point> 0 ⁰ C;

(ii) an emulsifier component and

(iii) optionally water

at a temperature in a first temperature range, wherein the first temperature range is above the melting point of component (i), and wherein the optionally present water produces a w / o emulsion and has a weight fraction which is less than the sum of the weight proportions of the components ( i) and (ii);

(b) adding water to the mixture, after complete addition of the water there is an o / w emulsion; (c) cooling the o / w emulsion of step (b) to a temperature in a second temperature range which is below the melting point of component (i); and

(d) optionally adding an at least partially water-miscible organic solvent component (iv) in which the paraffin-inhibiting component is insoluble.

The present object is likewise achieved by a paraffin inhibitor formulation obtainable from the preparation process according to the invention.

It has been found that, due to the manufacturing process according to the invention, a formulation can be obtained which has the paraffin inhibitor component in a fine and stable distribution, which is supported by the emulsifier component. In this way, a paraffin inhibitor formulation can be obtained which has a comparatively high proportion of paraffin inhibitor component, so that the formulation can be stored and transported in a space-saving manner and, moreover, a simple metered addition is made possible. In addition, a phase separation can be avoided, which leads to an increased storage stability.

The solids content of the formulation to be used can be adjusted individually by subsequent addition of water or by addition of an at least partially water-miscible organic solvent component (IV) in which the paraffin inhibitor component is insoluble.

In addition, the pour point of the pour point or Paraffininhibitor- Depressant- formulation itself by adding the organic solvent component (IV) may be adjusted, whereby it is possible to obtain a pour point of -50 ⁰ C.

In the context of the present invention, the term "inhibitor" or "inhibition" means that the paraffin crystal formation in oil as such and / or an undesired orientation and / or shape of the crystals is avoided or at least reduced. This leads to a reduction or absence of deposition or precipitation of paraffin or to a reduction of the pour point.

In the process according to the invention for the preparation of a paraffin inhibitor formulation, in step (a) the production of a mixture is carried out - A -

(i) a waxy paraffin inhibitor component having a melting point> 0 ⁰ C.

In the context of the present invention, the term melting point is also used for simplifying purposes when the paraffin inhibitor component has a melting range, in which case the limit of the range represents the melting point in the sense of the present invention, which leaves the component as completely liquid or completely solid.

The term "waxy" in the context of the present invention is to be understood as meaning that component (i) has waxy properties, which are characterized in particular by the fact that the substances or mixtures melt without decomposition and have a relatively low viscosity and high already above the melting point These include substances or mixtures of substances that are of natural, semi-synthetic or synthetic origin, but waxes in the narrower sense are not just those.Waxes in the narrower sense are mixtures of substances with as main component esters of higher fatty acids contain higher primary alcohols.

In addition, it is possible that the paraffin inhibitor component has several inhibitors, so that multiple melting point and / or melting ranges are possible. Again, the component should be completely liquid (melted) or solid.

For step (a) of the process according to the invention for preparing a paraffin inhibitor formulation, all melting points must be above 0 ^° C.

In addition, the mixture according to the invention contains an emulsifier component (ii) which may contain one or more emulsifiers or surfactants.

Finally, the mixture may already contain water, the optionally present water having a weight fraction which is less than the sum of the weight proportions of the components (i) and (ii). This serves for the purpose of initially introducing a water-in-oil (w / o) emulsion before adding further water in step (b) of the process according to the invention for preparing a paraffin inhibitor formulation.

Typically, the desired amount of water will be partially charged to produce an emulsion and the remainder added after obtaining the mixture in step (b) of the process of the invention for preparing a paraffin inhibitor formulation. In step (a) of the process of the present invention for preparing a paraffin inhibitor formulation, prior to performing step (b), it is required that the paraffin inhibitor component be in a molten state. Therefore, to produce an emulsion, a corresponding temperature must be selected that is above the melting point of the paraffin inhibitor component.

The production of a mixture in step (a) of the process according to the invention for the preparation of a paraffin inhibitor formulation can be effected, for example, by initially introducing a portion of water and then adding the paraffin inhibitor component (i) and the emulsifier component (ii). However, it will be apparent to one of ordinary skill in the art that a different order of the particular steps may be used.

The desired temperature may be adjusted by simply heating before and / or during and / or after the addition of components (i) and (ii). It is not necessary that the temperature remains constant.

In addition, the formulation may have further constituents which are advantageously present in dissolved form. It is also possible that these components are added in a later step. These may be active substances required in the production of crude oil, such as, for example, corrosion inhibitors or scale inhibitors.

In step (b) of the process according to the invention for preparing a paraffin inhibitor formulation, water is added to the mixture, after complete addition of the water an oil-in-water (o / w) emulsion is present. Care must be taken here that no precipitations occur. This can be ensured by the fact that the water to be added already has the desired temperature.

Subsequently, in step (c) of the process according to the invention for preparing a paraffin inhibitor formulation, the cooling of the resulting o / w emulsion from step (b) to a temperature in a second temperature range, which is below the melting point of component (i).

This solidifies the paraffin inhibitor component so that it is present as a finely divided solid in the formulation. In addition, in step (d) of the process according to the invention for preparing a paraffin inhibitor formulation, an organic solvent component (iv) which is at least partially miscible with water and in which the paraffin inhibitor component is insoluble can be added. The paraffin inhibitor component should preferably be less than 1% by weight soluble in component (iv). This serves to ensure that the paraffin inhibitor component is still present as a fine distribution of a solid.

The paraffin inhibitor formulation thus obtained thus contains at least one paraffin inhibitor component (i), an emulsifier component (ii), water and optionally an organic solvent component (iv).

As already stated above, the paraffin inhibitor formulation may also contain further constituents which are expediently present in dissolved form. The choice of the organic solvent component (iv) and its content in the formulation may optionally be such that further substances are present in dissolved form in the formulation.

The paraffin inhibitor component (i) may be a paraffin inhibitor known in the art or a mixture thereof. In particular, polymeric paraffin inhibitors are typically not pure single compounds. Rather, it is usually a production-related mixture of very similar individual compounds.

Examples of such inhibitors are polymers based on ethylene / vinyl acetate, acrylic acid, methacrylic acid, olefin / maleic acid or their anhydride or fatty acids which are reacted with fatty alcohols or their amines to give esters, amides or imides.

Further examples of paraffin inhibitors are described by D. Alvares et al., Petroleum Science and Technology 18 (2000), 195-202 and by H. S. Ashbaugh et al., Energy and Fuels 19 (2005), 138-144.

Particularly preferred paraffin inhibitors are branched hydrocarbons which have carboxylate groups which are partially or completely esterified with a linear paraffin alcohol or mixtures of fatty alcohols. Preferably, the branched hydrocarbons are copolymers of Cio-C ₄ o-α-olefins with maleic anhydride having a molecular weight of 2 to 40 kDa, preferably 5 to 30 kDa. Further preferred are C ₂ -C ₃ O-α-olefins, especially C ₂ ° C ₂₄ olefins. The linear paraffin alcohol is preferably a Cio-C ₄ -alcohol or a mixture thereof. More preferred are C ₅ -C ₃₀ -alcohols.

The at least partially esterified polymers preferably have a degree of esterification which depends on the basic skeleton used. Thus, it makes sense if at least 50% of the carboxylate functions in the case of poly (meth) acrylates and copolymers containing maleic anhydride are at least 25% esterified.

The paraffin inhibitor component may have further constituents in addition to the inhibitor itself. These may be, for example, solvents. Here, in particular organic, water-immiscible solvents can be used, which can also partially solve the inhibitor. In the context of the present invention, it is only necessary for the paraffin inhibitor component to have a melting point or melting range as indicated above. If the paraffin inhibitor component has multiple ingredients, it is necessary for the emulsion to have all ingredients in a molten or dissolved state, with at least the paraffin inhibitor in the prepared formulation not being in dissolved form.

The emulsifier component (ii) may contain one or more surfactants (surfactant mixture).

The surfactants used may be anionic, nonionic, amphoteric or cationic. It is also possible to use mixtures of the surfactants mentioned. Preferred formulations contain nonionic surfactants and mixtures thereof with other surfactants.

Suitable anionic surfactants are sulfates, sulfonates, carboxylates, phosphates and mixtures thereof. Suitable cations here are alkali metals, such as sodium or potassium or alkaline earth metals, such as. For example, calcium or magnesium and ammonium, substituted ammonium compounds including mono-, di- or triethanolammonium cations and mixtures thereof. Among the anionic surfactants, alkyl ester sulfonates, alkyl sulfates, alkyl ether sulfates, alkylbenzenesulfonates, secondary alkanesulfonates and soaps are preferred. These are described below.

Alkyl ester sulfonates include linear esters of C ₈ -C ₂ o-carboxylic acids (fatty acids) which are sulfonated with gaseous SO _3, as for example in "The Journal of the American OiI Chemists Society," 52 (1975), p. 323- 329, is described. Suitable starting materials are natural fats such. As sebum, coconut oil and palm oil, but also be fats of a synthetic nature. Preferred alkyl ester sulfonates are compounds of the formula

R ¹ - CH-COR

SO ₃ M

wherein R ^{1 is} a C ₈ -C ₂ o-hydrocarbon radical, preferably alkyl, and R a -C ₆ - hydrocarbon radical, preferably alkyl. M is a cation which forms a water-soluble salt with the alkyl ester sulfonate. Suitable cations are sodium, potassium, lithium or ammonium cations such as monoethanolamine, diethanolamine and triethanolamine. Preferably, R ¹ C _O -C ₆ alkyl and R is methyl, ethyl or isopropyl. Most preferred are methyl ester sulfonates in which R ^{1 is} Cio-Ci ₆ alkyl.

Alkyl sulfates are water-soluble salts or acids of the formula ROSO3M, wherein R is a C ₁ 0-C ₂₄ hydrocarbon radical, preferably an alkyl or hydroxyalkyl radical with Cio-C _2O - alkyl, more preferably a Ci ₂ -Ci ₈ alkyl or hydroxyalkyl radical , M is hydrogen or a suitable cation, for example an alkali metal cation, preferably sodium, potassium, lithium or an ammonium or substituted ammonium cation, preferably a methyl, dimethyl and trimethylammonium cation or a quaternary ammonium cation, such as the tetramethylammonium and dimethylpiperidinium cations and alkylamines such as ethylamine, diethylamine, triethylamine and mixtures thereof derived quaternary ammonium cations.

Alkyl ether sulfates are water soluble salts or acids of the formula RO (A) _m SO3M wherein R is an _O unsubstituiertenCi -C ₂₄ alkyl or hydroxyalkyl group, preferably a C ₂ -C ₂₀ alkyl or hydroxyalkyl, more preferably a C ₂ -C ₈ Alkyl or hydroxyalkyl radical. A is an ethoxy or propoxy moiety, m is a number greater than 0, preferably between about 0.5 and about 6, more preferably between about 0.5 and about 3, and M is a hydrogen atom or a cation such as, for example, , For example, sodium, potassium, lithium, calcium, magnesium, ammonium or a substituted ammonium cation. Examples of substituted ammonium cations include methyl, dimethyl, trimethylammonium and quaternary ammonium cations such as tetramethylammonium and dimethylpiperidinium cations and those derived from alkylamines such as ethylamine, diethylamine, triethylamine or mixtures thereof. Examples which may be mentioned Ci ₂ -Ci8 fatty alcohol ether sulfates, wherein the content at ethylene oxide units is 1, 2, 2.5, 3 or 4 moles per mole of the fatty alcohol ether sulfate and in which M is sodium or potassium.

In secondary alkanesulfonates, the alkyl group may be either saturated or unsaturated, branched or linear and optionally substituted with a hydroxyl group. The sulfo group can be at any position of the C chain, with the primary methyl groups at the beginning and end of the chain having no sulfonate groups. The preferred secondary alkanesulfonates contain linear alkyl chains of about 9 to 25 carbon atoms, preferably about 10 to about 20 carbon atoms and more preferably about 13 to 17 carbon atoms. The cation is, for example, sodium, potassium, ammonium, mono-, di- or triethanolammonium, calcium or magnesium and mixtures thereof. Sodium as a cation is preferred.

Other suitable anionic surfactants are alkenyl or alkylbenzenesulfonates. The alkenyl or alkyl group may be branched or linear and may optionally be substituted by a hydroxyl group. The preferred alkylbenzenesulfonates contain linear alkyl chains of about 9 to 25 carbon atoms, preferably from about 10 to about 13 carbon atoms, the cation being sodium, potassium, ammonium, mono-, di- or triethanolammonium, calcium or magnesium and mixtures thereof.

The term anionic surfactants also includes olefinsulfonates by sulfonation tion of C ₂ -C _{_24-6} -α-olefins are obtained with sulfur trioxide and subsequent neutralization, preferably C ₄ -C. Due to the preparation process, these olefin sulfonates may contain minor amounts of hydroxyalkanesulfonates and alkanedisulfonates. Specific blends of alpha-olefin sulfonates are described in U.S. 3,332,880.

Further preferred anionic surfactants are carboxylates, eg. B. fatty acid soaps and comparable surfactants. The soaps may be saturated or unsaturated and may contain various substituents such as hydroxyl groups or α-sulfonate groups. Preferred are linear saturated or unsaturated hydrocarbon radicals as hydrophobic moiety with about 6 to about 30, preferably about 10 to about 18 carbon atoms.

Suitable anionic surfactants are also: salts of acylaminocarboxylic acids; the acylsarcosinates formed by reaction of fatty acid chlorides with sodium sarcosinate in alkaline medium; Fatty acid-protein condensation products obtained by reacting fatty acid chlorides with oligopeptides; Salts of alkylsulfamide midocarboxylic acids; Salts of alkyl and alkylaryl ether carboxylic acids; Cs-C ₂₄ - olefin; sulfonated polycarboxylic acids prepared by sulfonation of the pyrolysis products of alkaline earth metal citrates, such as. As described in GB 1,082,179; alkylglycerol; acylglycerol sulfates; alkylphenol; primary paraffin sulfonate; alkyl phosphates; alkyl ether; Isethionates, such as acyl isethionates; N-acyl taurides; alkyl succinates; sulfosuccinates; Monoester of sulfosuccinates (especially saturated and unsaturated C ₂ -C ₈ monoesters) and diesters of sulfosuccinates (especially saturated and ungesättigteCi ₂ -C ₈ diesters); acyl sarcosinates; Sulfates of alkylpolysaccharides such as sulfates of alkyl polyglycosides, branched primary alkyl sulfates and alkyl polyglycol ethoxycarboxylates as those of the formula RO (CH ₂ CH ₂₎ _k CH ₂ COO ^"M ^+, wherein R is C ₈ to C ₂₂ alkyl, k is an integer from 0 to 10 and M is a cation; rosin acids or hydrogenated resin acids such as rosin or hydrogenated rosin or tall oil resins and tall oil rosin acids Other examples are described in "Surface Active Agents and Detergents" (Volumes I and II, Schwartz, Perry and Berch).

Suitable nonionic surfactants are, for example, the following compounds:

Polyethylene, polypropylene and polybutylene oxide condensates of alkylphenols.

These compounds include the condensation products of alkylphenols with a C -C ₂₀ alkyl group, which may be either linear or branched, with alkene oxides. Preference is given to compounds having about 5 to 25 mol of alkene oxide per mole of alkylphenol.

Condensation products of aliphatic alcohols with about 1 to about 25 mol ethylene oxide.

The alkyl chain of the aliphatic alcohols may be linear or branched, primary or secondary, and generally contains from about 8 to about 22 carbon atoms. Particularly preferred are the condensation products of Ci ₀ - to C ₂₀ alcohols with about 2 to about 18 mol ethylene oxide per mole of alcohol. The alkyl chain can be saturated or unsaturated. The alcohol ethoxylates may have a narrow range ("narrow range ethoxylates") or a broad homolog distribution of the ethylene oxide ("broad range ethoxylates").

Examples of commercially available nonionic surfactants of this type are, for example, the Lutensol ^® brands from BASF Aktiengesellschaft.

Particularly preferred are C ₆ -C ₈ fatty alcohol ethoxylates as constituent of components (ii). Still possible

Condensation products of ethylene oxide having a hydrophobic base formed by

Condensation of propylene oxide with propylene glycol.

The hydrophobic part of these compounds preferably has a molecular weight of between about 1,500 and about 1,800. The addition of ethylene oxide to this hydrophobic part leads to an improvement in water solubility. The product is liquid up to a polyoxyethylene content of about 50% of the total weight of the condensation product, which corresponds to a condensation with up to about 40 moles of ethylene oxide. Commercially available examples of this product class are, for example, Pluronic ^® brands from BASF Aktiengesellschaft.

Condensation products of ethylene oxide with a reaction product of propylene oxide and ethylenediamine.

The hydrophobic moiety of these compounds consists of the reaction product of ethylenediamine with excess propylene oxide and generally has a molecular weight of about 2,500 to 3,000. Ethylene oxide is added to this hydrophobic unit to a content of about 40 to about 80 wt .-% polyoxyethylene and a molecular weight of about 5,000 to 1 1,000. Commercially available examples of this class of compounds are, for example, the Tetronic ^® brands from BASF Corp.

Semipolar nonionic surfactants

This category of nonionic compounds includes water-soluble amine oxides, water-soluble phosphine oxides, and water-soluble sulfoxides each having an alkyl group of about 10 to about 18 carbon atoms. Semi-polar nonionic surfactants are also minoxides of the formula

O

R (OR ² ) N (R ¹ ) ₂ R here is an alkyl, hydroxyalkyl or alkylphenol group having a chain length of about 8 to about 22 carbon atoms. R ² is an alkylene or hydroxyalkylene group having about 2 to 3 carbon atoms or mixtures thereof, each R ¹ is an alkyl or hydroxyalkyl group having from about 1 to about 3 carbon atoms or a polyethylene oxide group having from about 1 to about 3 ethylene oxide units , and x represents a number from 0 to about 10. The R ¹ groups may be linked together via an oxygen or nitrogen atom and thus form a ring. Amine oxides of this type are especially C ₁ 0-C ₁ 8 alkyl dimethyl amine oxides and C ₈ -C ₂ -AI koxiethyl-dihydroxyethylamine.

- fatty acid amides

Fatty acid amides have the formula

wherein R is an alkyl group having from about 7 to about 21, preferably about 9 to about 17 carbon atoms and R ^{1 is} independently hydrogen, Ci-C ₄ alkyl, Ci-C ₄ -Hydroxyalkyl or (C ₂ H ₄ O ) _x H, where x varies from about 1 to about 3. Preferred are C ₈ -C ₂₀ amides, - monoethanolamides and diethanol amides -isopropanolamides.

Further suitable nonionic surfactants are alkyl and alkenyl oligoglycosides and fatty acid polyglycol esters or fatty amine polyglycol esters each having 8 to 20, preferably 12 to 18, carbon atoms in the fatty alkyl radical, alkoxylated triglycamides, mixed ethers or mixed formals, alkyloligoglycosides, alkenyloligoglycosides, fatty acid N-alkylglucamides, phosphine oxides, Dialkyl sulfoxides and protein hydrolysates.

Typical examples of amphoteric or zwitterionic surfactants are alkylbetaines, alkylamide betaines, aminopropionates, aminoglycinates or amphoteric imidazolinium compounds of the formula R ³

R ¹ (γ |)

wherein R ^{1 is} C ₈ -C ₂₂ alkyl or alkenyl, R ^{2 is} hydrogen or CH ₂ CO ₂ M, R ^{3 is} CH ₂ CH ₂ OH or CH ₂ CH ₂ OCH ₂ CH ₂ CO ₂ M, R ^{4 is} hydrogen, CH ₂ CH ₂ OH or CH ₂ CH ₂ COOM, Z is CO ₂ M or CH ₂ CO ₂ M, n is 2 or 3, preferably 2, M is hydrogen or a cation such as an alkali metal, alkaline earth metal, ammonium or alkanolammonium cation.

Preferred amphoteric surfactants of this formula are monocarboxylates and dicarboxylates. Examples of these are cocoamphocarboxypropionate, cocoamidocarboxypropionic acid, cocoamphocarboxyglycinate (also known as cocoamphodiacetate) and cocoamphoacetate.

Further preferred amphoteric surfactants are alkyldimethylbetaines and alkyldipolyethoxybetaines having an alkyl radical having from about 8 to about 22 carbon atoms which may be linear or branched, preferably having from 8 to 18 carbon atoms and more preferably having from 12 to 18 carbon atoms.

Suitable cationic surfactants are substituted or unsubstituted straight-chain or branched quaternary ammonium salts of the type R ¹ N (CH ₃ ) ₃ ⁺ X ^" , R ¹ R ² N (CH ₃ ) ₂ ⁺ X ^" , R ¹ R ² R ³ N (CHa) ⁺ X ^" or R ¹ R ² R ³ R ⁴ N ⁺ X ^" . The radicals R ^1, R ^2, R ³ and R ⁴ are independently preferably an unsubstituted alkyl having a chain length of 8 to 24 carbon atoms, especially from 10 to 18 carbon atoms, hydroxyalkyl having 1 to 4 C-atoms, Phe nyl, C ₂ -C ₈ -alkenyl, C ₇ -C ₂₄ -aralkyl, (C ₂ H ₄ O) _x H, where x is an integer from 1 to 3, one or more ester groups containing alkyl radicals or cyclic quaternary amino be niumsalze. X is a suitable anion known to those skilled in the art.

The organic solvent component (iv) may contain one or more organic solvents, wherein at least one of these solvents, but preferably all solvents, are at least partially miscible with water. Further preferred is complete miscibility with water in the desired concentration range. Preferably, the organic solvent component (iv) is a monohydric or polyhydric alcohol. At least it is preferred if such an alcohol is included in component (iv).

Examples of mono- or polyhydric alcohols are methanol, ethanol, n-propanol, i-propanol, n-butanol, sec-butanol, i-butanol, tert-butanol, glycols such as ethylene glycol, propylene glycol, dipropylene glycol, glycerol , Polyalkylene glycols such as polyethylene glycol. Particularly preferred are methanol and ethanol. Very particular preference is given to methanol.

Preferably, the melting point of the component (i) is in the range of 5 ° C to 200 ⁰ C.

Further preferred is a range of 10 ⁰ C to 100 ° C. Further preferred is a range of 30 ⁰ C to 80 ⁰ C and particularly preferred is a range of 40 ⁰ C to 60 ⁰ C.

Accordingly, it is preferable that the first temperature range is in the range of more than 10 ° C and less than 250 ° C. More preferably, the first temperature range is in the range of more than 30 ⁰ C and less than 200 ⁰ C. More preferably, the first temperature range is in the range of more than 50 ° C and less than 150 ° C. Most preferably, the first temperature range is in the range of more than 60 ⁰ C and less than 100 ° C.

In addition, it is preferred that the second temperature range in the range from more than 1 ° C to less than 100 ⁰ C. Further preferably, the second temperature range is in the range of more than 1 ° C and less than 75 ° C. More preferably, the second temperature range is in the range of more than 1 ° C and less than 60 ⁰ C. More preferably, the second temperature range is in the range of 1 ° C to less than 40 ° C.

Most preferably, the second temperature range is at room temperature.

When choosing the first and second temperature range, however, it must be noted that the melting point of the paraffin inhibitor component is below the temperature of the first temperature range and above the temperature of the second temperature range. If this is complied with, a temperature stability with the addition of components is not required, but preferred.

In the method according to the invention for the preparation of a paraffin inhibitor formulation, the component proportions are preferably chosen such that a paraffin inhibitor Formulation is formed in which the components (i) to (iv) are contained with the following proportions by weight, based in each case on the total weight of the formulation:

(i) 10 to 70% by weight, more preferably 10 to 60% by weight, even more preferably 20 to 55% by weight of paraffin inhibitor component;

(ii) 1 to 30 wt%, more preferably 1 to 20 wt%, even more preferably 1 to 10 wt% emulsifier component;

(iii) from 1 to 89% by weight, more preferably from 20 to 89% by weight, even more preferably from 40 to 89% by weight, especially from 45 to 80% by weight of water;

(iv) 0 to 88 wt%, more preferably 1 to 80 wt%, more preferably 5 to 75 wt%, even more preferably 10 to 70 wt%, especially 20 to 60 wt% Solvent component.

An advantage of the method according to the invention for the preparation of a paraffin inhibitor formulation is that the paraffin inhibitor component is finely divided in the formulation. The paraffin inhibitor component in the formulation preferably has a mean particle diameter of less than 100 μm. Further more preferably, an average particle diameter of less than 10 microns and especially less than 1 micron is obtained. The small particle size avoids the particles separating despite the low viscosity of the formulation, i. swim up and coagulate / coalesce.

The determination of the average particle diameter can be determined by measuring methods known in the art. This can be done for example by means of light scattering.

It is expedient that steps (a) to (d) take place in the process according to the invention for the preparation of a paraffin inhibitor formulation with stirring.

Likewise, it may be expedient if a pH adjustment takes place before step (d). Here, an alkaline pH range is preferred. The resulting paraffin inhibitor formulation of this invention may serve as an additive in oil or oil refines, as well as in the transportation or storage of crude oil or crude raffinates.

The formulation according to the invention can be used in particular in a process for paraffin inhibition / pour point reduction of crude oil or crude raffinates, this process comprising the step:

Adding a formulation according to the invention to crude oil or a crude oil raffinate, wherein the crude oil or crude raffinate preferably has a temperature which is above the melting point of the paraffin inhibitor component.

It is preferred that the formulation is heated to a temperature above the melting point of the paraffin inhibitor component prior to addition. This can be done, for example, with the help of a water heater.

example

manufacturing:

First, wax, surfactant and 1/3 of the required pH-adjusted amount of water are submitted. These are heated to 85 ° C and emulsified at 2000 rpm with a propeller stirrer (Janke & Kunkel IKA Plant RW20). After 10 minutes, the remaining, 85 ° C warm water is added and stirred for 5 more minutes. Thereafter, the sample is cooled at 700 rpm to room temperature (at least below the melting temperature). Then the pH is checked and possibly readjusted. The pH adjustment of the water phase is carried out with HCl or N, N-dimethylethanolamine.

As a surfactant system, a Ci ₆ -C ₈ fatty alcohol ethoxylate mixture with an HLB of about 15 has been proven.

As the wax, the commercially available Basoflux PI was used 40, which has a melting range of about 50 ⁰ C.

Following cooling, particle sizes were determined using the Beckman Coulter LS13 320 Laser Diffraction Particle Size Analyzer. The results were as follows:

Storage test:

Storage at 20 ⁰ C and 60 ⁰ C over a week is no change of the particle size distribution. The product produced according to the invention remains stable.

If, in a process not according to the invention, the components are emulsified only at elevated temperature and stirred with a propeller stirrer, a particle distribution is produced which has larger particles, which is detrimental to the stability.

Claims

- 1 patent claims

A process for preparing a paraffin inhibitor formulation comprising the steps

(a) producing a mixture containing

(i) a waxy paraffin-inhibiting component having a melting point

> 0 ° C;

(ii) an emulsifier component and (iii) optionally water

at a temperature in a first temperature range, wherein the first temperature range is above the melting point of component (i) and wherein the optional water produces a w / o emulsion and has a weight fraction less than the sum of the weight proportions of components (i) and

(ü) is;

(b) adding water to the mixture, wherein after complete addition of the water there is an o / w emulsion;

(c) cooling the o / w emulsion of step (b) to a temperature in a second temperature range which is below the melting point of component (i); and

2. The method according to claim 1, characterized in that the component (i) polymers based on ethylene / vinyl acetate, acrylic acid, methacrylic acid, olefin / maleic acid or its anhydride or fatty acids which with fatty alcohols or their amines to esters, amides or imides.

3. The method according to claim 1 or 2, characterized in that component (ii) contains a non-ionic surfactant or surfactant mixture.

4. The method according to any one of claims 1 to 3, characterized in that the component (iv) contains a monohydric or polyhydric alcohol. - 2 -

5. The method according to any one of claims 1 to 4, characterized in that the melting point of component (i) in the range of 5 ⁰ C to 200 ⁰ C.

6. The method according to any one of claims 1 to 5, characterized in that the first temperature range in the range of more than 10 ⁰ C and less than 250 ⁰ C.

7. The method according to any one of claims 1 to 6, characterized in that the second temperature range in the range of more than 1 ° C to less than 100 ⁰ C.

8. The method according to any one of claims 1 to 7, characterized in that the paraffin inhibitor formulation contains the components (i) to (iv) with the following proportions by weight, based in each case on the total weight of the formulation:

(i) 10 to 70% by weight of paraffin inhibitor component;

(ii) 1 to 30% by weight of emulsifier component;

(iii) 1 to 89% by weight of water;

(iv) 0 to 88% by weight of solvent component, wherein the weight fraction of water is greater than the sum of the weight proportions of components (i) and (ii).

9. The method according to any one of claims 1 to 8, characterized in that the paraffin inhibitor component in the formulation has an average particle diameter of <100 microns.

10. The method according to any one of claims 1 to 9, characterized in that the steps (a) to (d) are carried out with stirring.

1 1. A method according to any one of claims 1 to 10, characterized in that prior to step (d), a pH adjustment.

12. Paraffin inhibitor formulation obtainable from the preparation process according to one of claims 1 to 11.

13. Use of a formulation according to claim 12 as an additive in oil fields and in the transport or storage of crude oil or crude oil raffinates. - 3 -

14. A process for paraffin inhibition / pour point reduction of crude oil or crude raffinates comprising the step

Adding a formulation according to claim 12 to crude oil or a crude oil refinery.

15. The method according to claim 14, characterized in that the formulation is heated prior to adding to a temperature above the melting point of the paraffin inhibitor component.