Organoclay composition and preparation method therefor

Abstract

An organoclay composition. The organoclay composition can be used as a thickening rheology additive, and can be used in the fields of paint, ink, oil field drilling, etc. The organoclay composition mainly consists of montmorillonite, sepiolite, and a long-chain alkyl quaternary ammonium salt, and further comprises a small amount of an organic additive; and the organoclay composition is prepared by means of a specific process. The organoclay composition modified by the process not only has good dispersion, suspension and thickening properties, but also has the advantage of high rheological properties, and can effectively promote the application in low-polarity systems.

Description

An organic clay composition and a preparation method thereof TECHNICAL FIELD

[0001] The present application relates to an organic clay composition and a preparation method thereof, which can be used as a thickening rheological additive in the fields of paint, ink, oil drilling, etc. BACKGROUND

[0002] Clay is an important mineral raw material, which widely exists in nature and is generally formed by the weathering of aluminosilicate minerals on the earth's surface. The main components thereof are composed of various hydrated silicates, a certain amount of aluminum oxide, alkali metal oxide and alkaline earth metal oxide, and contain quartz, feldspar, mica and impurities such as sulfate, sulfide and carbonate. Clay minerals are generally fine particles, often in the colloidal size range, and are in the form of crystals or non-crystals, most of which are in the form of lamellar, and a few of which are in the form of tubular or rod-shaped. Among the clay minerals, bentonite, sepiolite, attapulgite and kaolin are most widely used. The microstructure of bentonite is mainly lamellar, and the microstructure of sepiolite and attapulgite is mainly rod-shaped or fibrous. The minerals with higher cation exchange capacity are bentonite and sepiolite.

[0003] Organic clay generally refers to clay modified by organic matter. The surface of clay particles is changed from hydrophilic to hydrophobic. It can be widely used in the fields of fine chemical industry such as oil drilling fluid, coating, ink and polymer nanocomposite, and used as a thickening rheological additive and functional additive.

[0004] The patent literature with the application number 201810060193.8 discloses a kind of composite organic clay for oil-based drilling fluid and its compounding method. The preparation of organic montmorillonite and fibrous organic clay is provided in the document, and the oil-based drilling fluid is prepared by compounding the organic montmorillonite and fibrous organic clay in a certain proportion. The organic montmorillonite and fibrous organic clay are prepared separately and then compounded to improve the temperature resistance in the oil-based drilling fluid formulation.

[0005] The patent literature with the patent number 201310034512.5 discloses a preparation method of modified organic bentonite. In the document, sodium-based bentonite is added to water to prepare a sodium-based bentonite suspension; cetyltrimethylammonium bromide is dissolved in water at room temperature, and then sorbitan oleate is added to prepare an emulsion; then the emulsion and the sodium-based bentonite suspension are mixed and oscillated, and then centrifuged, washed, dried and crushed to obtain the modified organic bentonite, which is used as an additive for white oil-based drilling fluid.

[0006] Patent No. 201710265478.0 invention patent literature, discloses a kind of preparation method of novel organic modified sepiolite and the application of the organic modified sepiolite. In the paper, sepiolite is purified first, then modified by cationic modifier and anionic modifier to obtain organic modified sepiolite, the cationic modifier is quaternary ammonium salt with 14-18 carbon, and the anionic modifier is sodium dodecyl sulfate or sodium hexadecyl sulfate. Organic modified sepiolite has good dispersibility, thixotropy and high viscosity, which meets the use requirements of oil-based drilling.

[0007] Application No. 201610782449.7 invention patent literature, discloses a kind of preparation method of organic bentonite. In the paper, calcium-based bentonite is used as raw material, sodium carbonate is added to obtain sodium-based bentonite slurry, then polyacrylamide is added for reaction, pressure filtration is carried out, then dibutyl phthalate (emulsifier) is added for modification, and then it is transferred into a mixing machine to mix with dimethyl octadecyl benzyl ammonium chloride to obtain organic bentonite.

[0008] Patent No. 201110235817.3 invention patent literature, discloses a kind of preparation method of high-performance organic bentonite. In the paper, sodium-based bentonite is used as raw material, two types of modifiers are used for modification, one is quaternary ammonium salt (one of hexadecyl trimethyl ammonium chloride, hexadecyl pyridine, octadecyl trimethyl ammonium chloride and octadecyl dimethyl benzyl ammonium chloride), and the other is intercalation agent (one of caprolactam, fatty alcohol polyoxyethylene ether AEO and octadecyl polyoxyethylene ether). The prepared organic bentonite is beneficial to improve the rheological property and carrying capacity of drilling fluid.

[0009] In summary, the modification of organic clay mainly aims at clay minerals such as bentonite, sepiolite and fibrous clay, and the modifier is mainly quaternary ammonium salt with different carbon chain lengths. In order to improve the suspension stability of organic clay in oil system, nonionic or anionic surfactant is added based on quaternary ammonium salt modification to achieve synergistic effect.

[0010] The application performance of organic clay in the fields of paint, ink and oil field drilling is mainly reflected in its thickening, suspending and thixotropic properties in the corresponding fields. The use of a single type of clay to prepare organic clay often shows insufficient thickening or suspending performance. The present invention aims to select suitable clay for compounding and prepare organic clay products with high thickening performance by optimizing the modification aid.

[0011] SUMMARY

[0012] The present invention solves the above problems and provides an organic clay composition. The organic clay composition of the present invention has the advantage of high rheological property.

[0013] The technical scheme of the present application to solve the above problems is as follows:

[0014] An organic clay composition mainly composed of montmorillonite, sepiolite and long chain alkyl quaternary ammonium salt; the organic clay composition comprises the following components by mass fraction:

[0015] montmorillonite: 50-70,

[0016] sepiolite: 10-30,

[0017] long chain alkyl quaternary ammonium salt: 30-50,

[0018] auxiliary agent: 1.1-15.

[0019] As a preferred embodiment of the above technical scheme, the montmorillonite is selected from one or both of sodium-based montmorillonite and artificial sodiumized montmorillonite; the auxiliary agent comprises auxiliary agent A and auxiliary agent B, the auxiliary agent A is selected from one or more of low molecular weight polyacrylate (molecular weight 500-5000), low molecular weight polyacrylate (molecular weight 500-5000) and hydroxyl carboxylic acid salt; the addition amount of the auxiliary agent A is 0.1-5% of the mass of the clay powder; the auxiliary agent B is selected from one or more of oleic acid amide, fatty acid amide, lactic acid fatty acid amide, stearic acid amide, oleate, linoleate and ricinoleate; the amount of the auxiliary agent B is 1-10% of the mass of the clay powder.

[0020] Another object of the present application is to provide a preparation method of the above clay composition.

[0021] A preparation method of an organic clay composition, comprising the following steps:

[0022] 1) dispersing the clay powder in water, stirring, centrifuging and purifying to form a suspension with a concentration of 2-6 wt%;

[0023] 2) adding a pH regulator to the suspension to adjust the pH of the slurry to 5-9, and stirring at a constant temperature of 40-80°C for 0.5-1 hour;

[0024] 3) adding auxiliary agent A, and stirring at a constant temperature of 40-80°C for 0.5-1 hour;

[0025] 4) adding long chain alkyl quaternary ammonium salt modification, and stirring at a constant temperature of 40-80°C for 1-10 hours;

[0026] 5) adding auxiliary agent B, and stirring at a constant temperature of 40-80°C for 0.5-1 hour;

[0027] 6) adding a pH regulator to adjust the pH of the slurry to 8-10, and stirring at a constant temperature of 40-80°C for 0.5-1 hour;

[0028] 7) filtering, washing, drying and crushing to obtain the product;

[0029] The aid A is selected from one or several of low molecular weight polyacrylate (molecular weight 500-5000), low molecular weight polyacrylate ester (molecular weight 500-5000), hydroxyl carboxylic acid salt; the addition amount of aid A is 0.1-5% of the mass of the clay powder;

[0030] The aid B is selected from one or several of oleic acid amide, fatty acid amide, lactic acid fatty acid amide, stearic acid amide, oleic acid ester, linoleic acid ester, ricinoleic acid ester; the amount of aid B is 1-10% of the mass of the clay powder.

[0031] As a preference, the addition amount of aid A is 0.2-3% of the mass of the clay powder.

[0032] As a preference, the addition amount of aid B is preferably 2-7% of the mass of the clay powder.

[0033] As a preference, the clay powder in step 1) comprises montmorillonite and sepiolite, and the montmorillonite is selected from one or both of sodium-based montmorillonite and artificial sodiumized montmorillonite.

[0034] As a preference, the pH regulator in step 2) and step 6) is selected from one or several of sulfuric acid, hydrochloric acid, triethanolamine, sodium hydroxide.

[0035] As a preference, the structure formula of the long-chain alkyl quaternary ammonium salt in step 4) is:

[0036] In which M is chloride ion or bromide ion;

[0037] In which R1 is CH3(CH2) n , n = 11-21;

[0038] In which R2 is CH3- or CH3(CH2) n , n = 11-21;

[0039] In which R3, R4 is CH3-.

[0040] As a preference, the long-chain alkyl quaternary ammonium salt in step 4) is composed of two components of quaternary ammonium salt A and quaternary ammonium salt B, R2 of quaternary ammonium salt A is CH3(CH2) n , n = 11-21; R2 of quaternary ammonium salt B is CH3-; in which the amount of quaternary ammonium salt A is 15-50% of the mass of the clay, and the amount of quaternary ammonium salt B is 10-40% of the mass of the clay.

[0041] The purpose of step 4) is to intercalate modify the viscosity material, wherein the quaternary ammonium salt A has obvious effect on increasing the interlayer spacing of montmorillonite, and the quaternary ammonium salt B has the effect of supplementing intercalation on clay. The sample prepared by using the two quaternary ammonium salts at the same time has good dispersion, suspension and thickening properties.

[0042] The purpose of step 5) is to intercalate the non-ionic organic molecules into the interlayer of clay by adsorption principle, so as to have emulsifying and dispersing effect, and the step has obvious promoting effect on the application of the product in low polarity system.

[0043] As preferred, the moisture content of the product obtained after drying and crushing in step 7) is ≤5%, and the fineness of the dry powder is ≤200 mesh.

[0044] In summary, the present application has the following beneficial effects:

[0045] The organic clay composition of the present application is mainly composed of montmorillonite, sepiolite and long-chain alkyl quaternary ammonium salt, and contains a small amount of organic auxiliary agent, and is prepared by a specific process. The organic clay composition modified by the process of the present application has the advantages of good dispersibility, suspensibility and thickening property, and high rheological property, which can effectively promote the application in low polarity system. DETAILED DESCRIPTION

[0046] In order to deepen the understanding of the present application, the present application will be further described in combination with the following implementation examples. The implementation examples are only used to explain the present application, and do not constitute the limitation of the protection scope of the present application.

[0047] Implementation example 1:

[0048] 1000g of sodium-based montmorillonite powder is weighed, 20kg of water is added, and the mixture is fully stirred and dispersed, and then centrifuged and purified to obtain a purified sodium-based montmorillonite suspension, and the solid content of the suspension is 30g / L. 5L of the purified sodium-based montmorillonite suspension is taken into a reactor, and the temperature is raised to 70℃ and kept constant temperature stirring; dilute sulfuric acid is added to adjust the slurry pH to 7-8, and stirred for 30 minutes; 3g of low molecular weight sodium polyacrylate (2% of soil) is added, and the temperature is kept at 70℃ and stirred for 1h; 70g of dioctadecyl dimethyl ammonium chloride (47% of soil) and 40g of octadecyl trimethyl ammonium chloride (27% of soil) are added, and the temperature is kept at 70℃ and stirred for 2h; 7.5g of oleic acid amide (5% of soil) is added, and the temperature is kept at 70℃ and stirred for 1h; sodium hydroxide solution is added to adjust the slurry pH to 8-9, and the temperature is kept at 70℃ and stirred for 30 minutes; then the temperature is cooled to room temperature, and then filtered, washed and dried to obtain a sample, which is labeled as FH-1.

[0049] Implementation example 2:

[0050] Take 500g sepiolite powder, add 10kg water, fully stir and disperse, centrifugal purification to obtain purified sepiolite suspension. Test the solid content of the suspension to be 20g / L. Take 5L purified sepiolite suspension in the reactor, heat to 70℃ and keep constant temperature stirring; add dilute sulfuric acid, adjust the slurry pH to 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2g, keep constant temperature stirring at 70℃ for 1h; add dioctadecyl dimethyl ammonium chloride 47g, octadecyl trimethyl ammonium chloride 27g, keep constant temperature stirring at 70℃ for 2h; add oleic acid amide 5g, keep constant temperature stirring at 70℃ for 1h; add sodium hydroxide solution, adjust the slurry pH to 8-9, keep constant temperature stirring at 70℃ for 30 minutes, cool to room temperature, filter, wash, dry, crush to obtain the sample, labeled as FH-2.

[0051] Example 3:

[0052] Take 4L purified sodium-based montmorillonite suspension in Example 1 and 1L purified sepiolite suspension in Example 2, fully stir and mix to obtain a mixed clay suspension, test the solid content of the suspension to be 28g / L. Heat the mixed clay suspension to 70℃ and keep constant temperature stirring; add dilute sulfuric acid, adjust the slurry pH to 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2.8g, keep constant temperature stirring at 70℃ for 1h; add dioctadecyl dimethyl ammonium chloride 66g, octadecyl trimethyl ammonium chloride 37.8g, keep constant temperature stirring at 70℃ for 2h; add oleic acid amide 7g, keep constant temperature stirring at 70℃ for 1h; add sodium hydroxide solution, adjust the slurry pH to 8-9, keep constant temperature stirring at 70℃ for 30 minutes, cool to room temperature, filter, wash, dry, crush to obtain the sample, labeled as FH-3.

[0053] Example 4:

[0054] Take 3L purified sodium-based montmorillonite suspension in Example 1 and 2L purified sepiolite suspension in Example 2, fully stir and mix to obtain a mixed clay suspension, test the solid content of the suspension to be 26g / L. Heat the mixed clay suspension to 70℃ and keep constant temperature stirring; add dilute sulfuric acid, adjust the slurry pH to 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2.6g, keep constant temperature stirring at 70℃ for 1h; add dioctadecyl dimethyl ammonium chloride 61g, octadecyl trimethyl ammonium chloride 35g, keep constant temperature stirring at 70℃ for 2h; add oleic acid amide 6.5g, keep constant temperature stirring at 70℃ for 1h; add sodium hydroxide solution, adjust the slurry pH to 8-9, keep constant temperature stirring at 70℃ for 30 minutes, cool to room temperature, filter, wash, dry, crush to obtain the sample, labeled as FH-4.

[0055] Example 5:

[0056] Take the purified sodium-based montmorillonite suspension 2.5L in the implementation example 1, take the purified sepiolite suspension 2.5L in the implementation example 2, mix well, get mixed clay suspension, test suspension solid content is 25g / L. The mixed clay suspension is heated to 70℃, and constant temperature stirring is kept; add dilute sulfuric acid, adjust the slurry pH 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2.5g, 70℃ constant temperature stirring 1h; Add ditetradecyl dimethyl ammonium chloride 59g, octadecyl trimethyl ammonium chloride 34g, 70℃ constant temperature stirring 2h; Add oleic acid amide 6.2g, 70℃ constant temperature stirring 1h; Add sodium hydroxide solution, adjust the slurry pH 8-9, 70℃ constant temperature stirring 30 minutes, cool to room temperature, filter, wash, dry, crush to get sample, labeled FH-5.

[0057] Implementation example 6:

[0058] Take the purified sodium-based montmorillonite suspension 4L in the implementation example 1, take the purified sepiolite suspension 1L in the implementation example 2, mix well, get mixed clay suspension, test suspension solid content is 28g / L. The mixed clay suspension is heated to 70℃, and constant temperature stirring is kept; add dilute sulfuric acid, adjust the slurry pH 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2.8g, 70℃ constant temperature stirring 1h; Add ditetradecyl dimethyl ammonium chloride 56g (40% soil), octadecyl trimethyl ammonium chloride 28g (20% soil), 70℃ constant temperature stirring 2h; Add oleic acid amide 7g, 70℃ constant temperature stirring 1h; Add sodium hydroxide solution, adjust the slurry pH 8-9, 70℃ constant temperature stirring 30 minutes, cool to room temperature, filter, wash, dry, crush to get sample, labeled FH-6.

[0059] Implementation example 7:

[0060] Take the purified sodium-based montmorillonite suspension 4L in the implementation example 1, take the purified sepiolite suspension 1L in the implementation example 2, mix well, get mixed clay suspension, test suspension solid content is 28g / L. The mixed clay suspension is heated to 70℃, and constant temperature stirring is kept; add dilute sulfuric acid, adjust the slurry pH 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2.8g, 70℃ constant temperature stirring 1h; Add ditetradecyl dimethyl ammonium chloride 56g (40% soil), octadecyl trimethyl ammonium chloride 28g (20% soil), 70℃ constant temperature stirring 2h; Add oleic acid amide 7g, 70℃ constant temperature stirring 1h; Add sodium hydroxide solution, adjust the slurry pH 8-9, 70℃ constant temperature stirring 30 minutes, cool to room temperature, filter, wash, dry, crush to get sample, labeled FH-6.

[0061] Implementation example 8:

[0062] Take the purified sodium-based montmorillonite suspension 4L in the implementation example 1, take the purified sepiolite suspension 1L in the implementation example 2, mix well, get the mixed clay suspension, test the suspension solid content is 28g / L. The mixed clay suspension is heated to 70℃, and constant temperature stirring is kept; add dilute sulfuric acid, adjust the slurry pH 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2.8g, 70℃ constant temperature stirring 1h; Add dioctadecyl dimethyl ammonium chloride 70g (50% soil), octadecyl trimethyl ammonium chloride 42g (30% soil), 70℃ constant temperature stirring 2h; Add sodium hydroxide solution, adjust the slurry pH 8-9, 70℃ constant temperature stirring 30 minutes, cool to room temperature, filter, wash, dry, crush to get the sample, labeled FH-9.

[0063] Implementation example 9:

[0064] Take the purified sodium-based montmorillonite suspension 4L in the implementation example 1, take the purified sepiolite suspension 1L in the implementation example 2, mix well, get the mixed clay suspension, test the suspension solid content is 28g / L. The mixed clay suspension is heated to 70℃, and constant temperature stirring is kept; add dilute sulfuric acid, adjust the slurry pH 7-8, stir for 30 minutes, add low molecular weight sodium polyacrylate 2.8g, 70℃ constant temperature stirring 1h; Add dioctadecyl dimethyl ammonium chloride 70g (50% soil), octadecyl trimethyl ammonium chloride 42g (30% soil), 70℃ constant temperature stirring 2h; Add sodium hydroxide solution, adjust the slurry pH 8-9, 70℃ constant temperature stirring 30 minutes, cool to room temperature, filter, wash, dry, crush to get the sample, labeled FH-9.

[0065] The sample in the implementation case is tested for rheological viscosity in white oil, and the test method is: take 10g of organic clay sample, disperse in 90g of white oil, stir and disperse, the stirring speed is 2000rpm, the stirring time is 10min, the temperature is kept constant at about 30℃ during stirring, and the prepared gel is placed in a rotary viscometer to test the viscosity. The test results are shown in Table 1.

[0066] As can be seen from the table, the sample prepared according to the patent scheme of the application has high thickening performance in the solvent.

[0067] Table 1: Rheological viscosity test data of sample

Claims

1. A method for preparing an organoclay composition, comprising the following steps: 1) dispersing clay powder in water, stirring, centrifuging, and purifying to form a suspension with a concentration of 2-6 wt%; 2) adding a pH regulator to the suspension, adjusting the pH of the slurry to 5-9, and stirring at a constant temperature of 40-80°C for 0.5-1 hour; 3) adding an additive A, and stirring at a constant temperature of 40-80°C for 0.5-1 hour; 4) adding a long-chain alkyl quaternary ammonium salt modifier, and stirring at a constant temperature of 40-80°C for 1-10 hours; 5) adding an additive B, and stirring at a constant temperature of 40-80°C for 0.5-1 hour; 6) adding a pH regulator, adjusting the pH of the slurry to 8-10, and stirring at a constant temperature of 40-80°C for 0.5-1 hour; 7) filtering, washing, drying, and crushing to obtain a product; the additive A is selected from one or more of low-molecular-weight polyacrylate, low-molecular-weight polyacrylate ester, and hydroxyl carboxylic acid salt; the additive A is added in an amount of 0.1-5% of the mass of the clay powder; the additive B is selected from one or more of oleic acid amide, fatty acid amide, lactic acid fatty acid amide, and stearic acid amide; the additive B is used in an amount of 1-10% of the mass of the clay powder; the pH regulator in step 2) and step 6) is selected from one or more of sulfuric acid, hydrochloric acid, triethanolamine, and sodium hydroxide.

2. The method of preparing an organoclay composition according to claim 1, characterized in that: the additive A is added in an amount of 0.2-3% of the mass of the clay powder.

3. The method for preparing an organoclay composition according to claim 1, characterized in that: the additive B is added in an amount of 2-7% of the mass of the clay powder.

4. The method for preparing an organoclay composition according to claim 1, characterized in that: the clay powder in step 1) comprises montmorillonite and sepiolite, and the montmorillonite is selected from one or both of sodium-based montmorillonite and artificially sodiumized montmorillonite.

5. The method for preparing an organoclay composition according to claim 1, characterized in that: The structural formula of the long chain alkyl quaternary ammonium salt in Step 4) is: wherein M is a chloride ion or a bromide ion; wherein R1is of the formula CH3(CH2) n - and n = 11-21. wherein R2is of the structure CH3- or CH3(CH2) n - and n = 11 to 21; wherein R3 and R4 have the structure of CH3-.

6. The method for preparing an organoclay composition according to claim 1, characterized in that: The long chain alkyl quaternary ammonium salt in step 4) consists of two components, quaternary ammonium salt A and quaternary ammonium salt B, R2of quaternary ammonium salt A is CH3(CH2) n , n = 11-21; R2of quaternary ammonium salt B is CH3-; wherein the amount of quaternary ammonium salt A is 15-50% of the mass of the clay, and the amount of quaternary ammonium salt B is 10-40% of the mass of the clay.

7. The method for preparing an organoclay composition according to claim 1, characterized in that: the moisture content of the product obtained after drying and crushing in step 7) is ≤5%, and the fineness of the dry powder is ≤200 mesh.

Images