Dendritic multi-adsorption-site clay stabilizer and preparation method thereof

Abstract

According to the dendritic multi-adsorption-site clay stabilizer and the preparation method thereof, the clay stabilizer has multiple quaternary ammonium salt adsorption sites, effective adsorption can be achieved on the surface and interlayer of clay, the adsorption performance of the clay stabilizer can be effectively improved through the multi-point adsorption effect, and the desorption probability at the high temperature is reduced; meanwhile, due to the fact that the dendritic structure has very high hydrophobicity, water molecules can be effectively prevented from entering clay interlayers, and hydration expansion of clay can be well inhibited. The clay stabilizer provided by the invention has a better effect of inhibiting hydration expansion of clay, excellent anti-expansion performance, strong washing resistance and good temperature resistance, the anti-expansion rate of the clay stabilizer reaches 90% or above, the washing resistance reaches 100%, and the temperature resistance reaches 200 DEG C.

Description

Technical Field

[0001] The invention relates to a dendritic multi-adsorption site clay stabilizer and a preparation method thereof, belonging to the technical field of petroleum engineering. Background Art

[0002] Clay is a common mineral in formation rocks, which has the property of swelling when it encounters water. Usually, when the oil reservoir contains 5% to 20% clay, it is considered to be an oil layer with a high clay content. During the oil field development process (water injection, acidification, fracturing), if the measures are not appropriate, these clays will swell, disperse, and migrate when they encounter external water or water-based substances. During the swelling process, the clay absorbs water into the crystal structure, resulting in an increase in the volume of the clay, thereby blocking the formation pores, causing water-sensitive damage, and affecting the oil and gas production of the reservoir.

[0003] The most common method to solve water-sensitive damage is to add clay stabilizers to the injected water. Clay stabilizers can effectively adsorb on the surface of clay, preventing water-sensitive minerals in the reservoir from hydrating, expanding, and dispersing and migrating, thereby preventing damage to the oil and gas layers and ensuring that the effect of oil field development is not affected.

[0004] The commonly used clay stabilizers currently include inorganic salts, cationic polymers and quaternary ammonium salts. Inorganic salts are the earliest used clay stabilizers, mainly using inorganic salt ions such as K ＋ Embedded in the clay crystal structure to neutralize the electronegativity of the clay, but inorganic salt clay stabilizers have weak binding force with the formation and poor ability to prevent clay migration. Organic cationic polymers dissociate in water to produce high-positive polymer cations. Since the cations are in large numbers on the repeating units of the structure. They can form multi-point adsorption with clay particles to form a protective film, effectively preventing the expansion and migration of clay particles. However, the molecular weight of cationic polymers is too large, which can easily block the pores of the formation and cause reservoir damage. Quaternary ammonium salt clay stabilizers have a low molecular weight and will not block the pores of the formation. At the same time, there are quaternary ammonium salt cations in their structure, which can bind to the clay surface and inhibit water molecules from entering the clay layer, effectively preventing clay hydration and expansion. However, most quaternary ammonium salt clay stabilizers have only one cation in their molecules, which can only form single-point adsorption with clay, have few adsorption sites, and are easy to desorb in high temperature environments, which seriously affects the effect of inhibiting clay hydration.

[0005] With the continuous deepening of oil resource exploration, the burial depth of oil reservoirs continues to increase, the temperature of oil reservoirs continues to rise, and the temperature resistance of chemical treatment agents used in oil and gas well operations continues to increase. Therefore, it is urgent to develop new high-temperature resistant and strongly adsorbed clay stabilizers to meet the needs of inhibiting clay swelling during oil reservoir development. Summary of the invention

[0006] The invention provides a dendritic multi-adsorption site clay stabilizer and a preparation method thereof. The clay stabilizer has multiple quaternary ammonium salt adsorption sites and can effectively adsorb on the clay surface and between layers. The multi-point adsorption effect can effectively improve its adsorption performance and reduce the probability of desorption at high temperature. At the same time, since its dendritic structure has strong hydrophobicity, it can effectively prevent water molecules from entering the clay interlayer and can better inhibit the hydration expansion of the clay.

[0007] The present invention achieves the above-mentioned purpose through the following technical solutions.

[0008] The reaction process of the dendritic tertiary amine compound is as follows: first, the raw material trialkylolamine reacts with hydrogen and ammonia under the action of a catalyst, and the alkyl alcohol in the structure is converted into alkylamine.

[0009]

[0010] By controlling the amount of ammonia added, the ammonia is kept in a state of insufficient amount. At this time, the generated amino compound will continue to react with the raw material trialkylolamine as an amine source.

[0011]

[0012] The reaction is continued in this way to generate a dendritic tertiary amine compound. The generated dendritic tertiary amine compound is further reacted with a halogenated hydrocarbon to obtain a dendritic quaternary ammonium salt compound.

[0013] The present invention provides a dendritic multi-adsorption site clay stabilizer, characterized in that: the structural formula of the dendritic multi-adsorption site clay stabilizer is: Wherein, R1 is methyl, ethyl or benzyl; R2 is C1-C3 alkyl, and X is halogen.

[0014] The present invention also provides a method for preparing the dendritic multi-adsorption site clay stabilizer, the preparation steps being: (1) Preparation of dendritic tertiary amine compounds: Add the raw material trialkylolamine to a reactor, then add a catalyst, replace it with nitrogen, introduce ammonia into the reactor, then introduce hydrogen into the reactor, stir and heat, depressurize and vent the reactor after the reaction, replace it with nitrogen, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Adding the dendritic tertiary amine compound obtained in step (1) into a reactor, then adding a halogenated hydrocarbon, and heating to react to obtain a dendritic quaternary ammonium salt compound.

[0015] The trialkyl alcohol is trimethanolamine, triethanolamine or triisopropanolamine.

[0016] The ratio of the amount of ammonia to the amount of trialkylolamine is 1-1.5:1.

[0017] The catalyst is a Ni / Al catalyst, wherein the content of Ni is 25-40% (wt%).

[0018] The reaction conditions for preparing the dendritic tertiary amine compound are as follows: the catalyst addition amount is 0.1-15% of the mass of the trialkylolamine, preferably 5-10%; the reaction temperature is 185-245° C., preferably 205-230° C., the hydrogen partial pressure is 1.0-4.5 MPa, preferably 1.5-3.0 MPa, and the reaction time is 3-6 h.

[0019] The halogenated hydrocarbon is methyl chloride, ethyl chloride or chlorobenzene.

[0020] The amount of the halogenated hydrocarbon and the trialkylolamine is 1-2:1.

[0021] The quaternization reaction conditions of the dendritic tertiary amine compound and the halogenated hydrocarbon are as follows: the reaction temperature is 60-95° C., preferably 75-85° C., and the reaction time is 2-6 hours.

[0022] The clay stabilizer provided by the invention can be used as an anti-swelling agent in water injection, acid fracturing and heavy oil thermal recovery.

[0023] The clay stabilizer provided by the present invention has a good effect of inhibiting clay hydration expansion, excellent anti-swelling performance, strong water washing resistance, and good temperature resistance. The anti-swelling rate of the clay stabilizer reaches more than 90%, the water washing resistance rate reaches 100%, and the temperature resistance reaches 200°C. Implementation

[0024] The present invention is described in detail below with reference to embodiments and comparative examples. Example 1

[0025] (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw material triethanolamine to a reactor, then add 10% Ni / Al catalyst (based on the mass of triethanolamine, the Ni content in the catalyst is 35%), replace with nitrogen three times, then pass 1 mol of ammonia into the reactor, then pass 1.5 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 205°C, and react for 5 hours. Then, depressurize the reactor and vent, replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 2 mol of methyl chloride, heat to 75° C., and react for 5 h to obtain a dendritic quaternary ammonium salt compound. Example 2

[0026] (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw material triethanolamine to a reactor, then add 7.5% Ni / Al catalyst (based on the mass of triethanolamine, the Ni content in the catalyst is 40%), replace with nitrogen three times, then pass 1 mol of ammonia into the reactor, then pass 2.0 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 230°C, and react for 4 hours. Then, depressurize the reactor and exhaust, replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 2 mol of methyl chloride, heat to 85° C., and react for 4 h to obtain a dendritic quaternary ammonium salt compound. Example 3

[0027] (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw material triethanolamine to a reactor, then add 15% Ni / Al catalyst (based on the mass of triethanolamine, the Ni content in the catalyst is 25%), replace with nitrogen three times, then pass 1.5 mol of ammonia into the reactor, then pass 2.5 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 185°C, and react for 6 hours. Then, depressurize the reactor and vent, replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 1 mol of chlorobenzene, heat to 95° C., and react for 2 h to obtain a dendritic quaternary ammonium salt compound. Example 4

[0028] (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw triethanolamine to a reactor, then add 5% Ni / Al catalyst (based on the mass of triethanolamine, the Ni content in the catalyst is 30%), replace with nitrogen three times, then pass 1.5 mol of ammonia into the reactor, then pass 3.0 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 245°C, and react for 3 hours. Then, depressurize the reactor and replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 1 mol of ethyl chloride, heat to 60° C., and react for 6 hours to obtain a dendritic quaternary ammonium salt compound. Example 5

[0029] (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw material trimethylolamine to a reactor, then add 0.1% Ni / Al catalyst (based on the mass of trimethylolamine, the Ni content in the catalyst is 35%), replace with nitrogen three times, then pass 1.2 mol of ammonia into the reactor, then pass 4.5 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 245°C, and react for 6 hours. Then, depressurize the reactor, exhaust, replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 1 mol of methyl chloride, heat to 90° C., and react for 3 h to obtain a dendritic quaternary ammonium salt compound. Example 6

[0030] (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw material triisopropanolamine to a reactor, then add 1% Ni / Al catalyst (based on the mass of triisopropanolamine, the Ni content in the catalyst is 35%), replace with nitrogen three times, then pass 1.3 mol of ammonia into the reactor, then pass 4.5 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 245°C, and react for 6 hours. Then, depressurize the reactor and vent, replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 1.75 mol of methyl chloride, heat to 80° C., and react for 3 h to obtain a dendritic quaternary ammonium salt compound. Example 7

[0031] (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw material triethanolamine to a reactor, then add 2.5% Ni / Al catalyst (based on the mass of triethanolamine, the Ni content in the catalyst is 35%), replace with nitrogen three times, then pass 1.4 mol of ammonia into the reactor, then pass 1.0 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 245°C, and react for 6 hours. Then, depressurize the reactor and vent, replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 1.25 mol of methyl chloride, heat to 70° C., and react for 4 hours to obtain a dendritic quaternary ammonium salt compound.

[0032] Comparative Example 1 Preparation of dendritic tertiary amine compounds: 1 mol of raw material triethanolamine is added to the reactor, and then 10% Ni / Al catalyst (based on the mass of triethanolamine, the Ni content in the catalyst is 35%) is added, and the reaction is replaced with nitrogen three times, and then 5 mol of ammonia is introduced into the reactor, and then 1.5 MPa of hydrogen is introduced into the reactor, and then the stirring of the reactor is turned on and heating is started. After heating to 205°C, the reaction is carried out for 5 hours. Then the reactor is depressurized and vented, and nitrogen is replaced twice. After the reaction product is distilled and dehydrated, the dendritic tertiary amine compound can be obtained.

[0033] Comparative Example 2 (1) Preparation of dendritic tertiary amine compounds: Add 1 mol of raw material triethanolamine to a reactor, then add 10% Ni / Al catalyst (based on the mass of triethanolamine, the Ni content in the catalyst is 35%), replace with nitrogen three times, then pass 5 mol of ammonia into the reactor, then pass 1.5 MPa of hydrogen into the reactor, then start stirring the reactor, start heating, heat to 205°C, and react for 5 hours. Then, depressurize the reactor and exhaust, replace with nitrogen twice, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Add the dendritic tertiary amine compound obtained in step (1) into a reactor, add 2 mol of methyl chloride, heat to 75° C., and react for 5 h to obtain a dendritic quaternary ammonium salt compound.

[0034] Test Example 1 According to the "SY / T5971-2016 Performance Evaluation Method of Clay Stabilizer for Water Injection", the anti-swelling rate test was carried out, and the steps are as follows: weigh 0.5g sodium bentonite, add it to a 10mL centrifuge tube, add deionized water to the 10mL mark, shake it well, let it stand at room temperature for 2h, put it into a centrifuge, centrifuge it at a speed of 1500r / min for 15min, and read the volume V2 of sodium bentonite in water. Use the same steps to replace the clean water with a certain concentration of clay stabilizer aqueous solution, and measure the volume V1 of the soil after centrifugation. Use kerosene instead of water to measure the volume V0 of the soil.

[0035]

[0036] In the formula: η—anti-swelling rate, %; V0—volume of sodium bentonite in kerosene, mL; V1—volume of sodium bentonite in clay stabilizer, mL; V2—volume of sodium bentonite in clean water, mL.

[0037] Test Example 2 The anti-swelling rate test steps after aging at 200°C are as follows: (1) Weigh 3.00 g of bentonite powder, accurate to 0.01 g, and load it into a high temperature and high pressure closed reactor; (2) Add 60 mL of 4% clay stabilizer solution, shake well to mix, place in an oven at 200±2℃ for 24 hours, and cool to room temperature; (3) Transfer all the clay mixture in the high-temperature and high-pressure closed reactor into a 100 mL beaker, shake it thoroughly, quickly take out 10 mL and add it to a glass centrifuge tube, put it into a centrifuge with automatic balancing function, centrifuge it at 1500r / min for 15 minutes, and read the expansion volume V1 of the bentonite. The anti-swelling rate calculation formula is as follows:

[0038] Where: V0 is the expansion volume of bentonite in kerosene; V1 is the expansion volume of bentonite in clay stabilizer aqueous solution; V2 is the expansion volume of bentonite in clean water; Test Example 3 The steps for testing washability are as follows: Pour out the supernatant in the centrifuge tube after centrifugation in the above test example 2, add deionized water to 10mL, stir thoroughly, let stand for 2h, and centrifuge at 1500r / min for 15min in a centrifuge. Finally, read the final volume V1 of the bentonite in the centrifuge tube. ′ .

[0039] Washability calculation formula:

[0040] Where: V1 is the expansion volume of bentonite in clay stabilizer aqueous solution, mL; V1 ′ V is the expansion volume of bentonite after washing, mL; V2 is the expansion volume of bentonite in clean water, mL.

[0041] Table 1 Sample evaluation results

[0042] From the results in the table, it can be seen that the dendritic clay stabilizer with multiple adsorption sites provided by the present invention has good anti-swelling performance both at room temperature and after aging at 200°C, indicating that the structure of multiple adsorption sites helps to prevent its desorption at high temperature, avoiding the phenomenon of decreased anti-swelling performance after high-temperature aging. In Comparative Example 1, since ammonia is in excess, most of the terminal amino groups in its product are primary amines, and a relatively complete dendritic structure cannot be formed. Even if the tertiary amine groups in its structure are quaternized, it has only a small number of quaternary ammonium ions, and the dendritic structure is imperfect, and the hydrophobicity of the structure is weak. Therefore, its anti-swelling performance at room temperature is lower than that of the dendritic clay stabilizer with multiple adsorption sites of the present invention. After aging at 200°C, this gap becomes significantly larger, mainly because the desorption phenomenon of the sample in the comparative example at high temperature causes its anti-swelling performance after high-temperature aging to deteriorate.

Claims

1. A dendritic multi-adsorption site clay stabilizer, characterized in that: The structural formula of the dendritic multi-adsorption site clay stabilizer is: Wherein, R1 is methyl, ethyl or benzyl; R2 is C1-C3 alkyl, and X is halogen.

2. The method for preparing the dendritic multi-adsorption site clay stabilizer according to claim 1, characterized in that: The preparation steps of the dendritic multi-adsorption site clay stabilizer are as follows: (1) Preparation of dendritic tertiary amine compounds: Add the raw material trialkylolamine to a reactor, then add a catalyst, replace it with nitrogen, introduce ammonia into the reactor, then introduce hydrogen into the reactor, stir and heat, depressurize and vent the reactor after the reaction, replace it with nitrogen, and distill and dehydrate the reaction product to obtain a dendritic tertiary amine compound; (2) Adding the dendritic tertiary amine compound obtained in step (1) into a reactor, then adding a halogenated hydrocarbon, and heating to react to obtain a dendritic quaternary ammonium salt compound.

3. The preparation method according to claim 2, characterized in that: The trialkyl alcohol is trimethanolamine, triethanolamine or triisopropanolamine.

4. The preparation method according to claim 2, characterized in that: The ratio of the amount of ammonia to the amount of trialkylolamine is 1-1.5:

1.

5. The preparation method according to claim 2, characterized in that: The catalyst is a Ni / Al catalyst, wherein the content of Ni is 25-40% (wt%).

6. The preparation method according to claim 2, characterized in that: The reaction conditions for preparing the dendritic tertiary amine compound are as follows: the catalyst addition amount is 0.1-15% of the mass of the trialkylolamine, preferably 5-10%; the reaction temperature is 185-245° C., preferably 205-230° C., the hydrogen partial pressure is 1.0-4.5 MPa, preferably 1.5-3.0 MPa, and the reaction time is 3-6 h.

7. The preparation method according to claim 2, characterized in that: The halogenated hydrocarbon is methyl chloride, ethyl chloride or chlorobenzene.

8. The preparation method according to claim 2, characterized in that: The amount of the halogenated hydrocarbon and the trialkylolamine is 1-2:

1.

9. The preparation method according to claim 2, characterized in that: The quaternization reaction conditions of the dendritic tertiary amine compound and the halogenated hydrocarbon are as follows: the reaction temperature is 60-95° C., preferably 75-85° C.; and the reaction time is 2-6 hours.

10. The dendritic multi-adsorption site clay stabilizer according to claim 1, characterized in that: The clay stabilizer is used as an anti-swelling agent in water injection, acid fracturing and heavy oil thermal recovery.

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