A high-temperature resistant and efficient clay stabilizer and its preparation method

Abstract

This invention relates to the field of oilfield additives technology, and provides a high-temperature resistant, high-efficiency clay stabilizer and its preparation method. The clay stabilizer comprises a self-made oligomeric organic ammonium salt containing a diphenyl ring and polyether segment structure, a benzyl quaternary ammonium salt, and KCl, exhibiting excellent temperature resistance and anti-swelling properties. The high-temperature resistant, high-efficiency clay stabilizer provided by this invention achieves an anti-swelling rate of over 85% at an addition dosage of only 0.1%, a temperature resistance of up to 300℃, and a water wash resistance of 100%. It can be used for anti-swelling applications in oilfield water injection and acid fracturing.

Description

Technical Field

[0001] This invention relates to a clay stabilizer with high-temperature resistance, belonging to the field of oilfield additives technology. Background Technology

[0002] Low-permeability reservoirs account for about 70% of my country's oil reserves. Hydraulic fracturing is often used to increase production in these reservoirs. However, during fracturing, clay minerals are prone to swelling upon contact with water, causing formation pore blockage, wellbore instability, and even collapse, severely impacting oil and gas production. Clay stabilizers are oilfield additives that act on clay minerals. They carry a positive charge and can adsorb onto the negatively charged surface of clay minerals, preventing water molecules from entering the interlayers of clay and thus inhibiting the hydration and dispersion of clay minerals.

[0003] Clay stabilizers mainly include inorganic salts, cationic surfactants, and organic cationic polymers. Inorganic salt clay stabilizers readily undergo cation exchange in solution, exhibiting poor stability and long-term effectiveness, and are unable to form multi-point adsorption. They also have poor erosion resistance and can harm formation microbial communities, causing soil compaction and posing significant environmental hazards. With the continuous development of oil reservoirs and the increasing reservoir temperature, cationic surfactant clay stabilizers are prone to decomposition at high temperatures, thus losing their clay-stabilizing effect. Organic cationic polymers containing amine groups are particularly effective in preventing clay hydration swelling and reducing particle dispersion and migration. They also possess strong temperature resistance, making them suitable for medium- and high-temperature reservoirs and showing broad application prospects. Summary of the Invention

[0004] In view of the problems of poor temperature resistance and the potential for damage to formations when added in large quantities, existing clay stabilizers provide a high-temperature resistant and efficient clay stabilizer and its preparation method. This clay stabilizer comprises a self-made oligomeric organic ammonium salt with a main chain containing a double benzene ring structure, a benzyl quaternary ammonium salt, and KCl. It has a temperature resistance of up to 300℃, and when added at a concentration of 0.1%, the anti-swelling rate reaches over 85%.

[0005] The high-temperature resistant and efficient clay stabilizer provided by this invention is characterized by comprising an oligomeric organic salt, a benzyl quaternary ammonium salt, and an inorganic salt KCl, wherein the oligomeric organic ammonium salt has the following structural formula:

[0006] Where n = 8~16.

[0007] Generally, the molar ratio of oligomeric organic ammonium salt, benzyl quaternary ammonium salt and KCl in the composition of the high-temperature resistant and efficient clay stabilizer is 1:20:12 to 1:30:18.

[0008] The method for preparing the oligomeric organic ammonium salt includes the following steps:

[0009] (1) Add bisphenol A polyoxyethylene ether, solvent, catalyst and activator to the reactor, introduce N2 gas into the reactor for replacement, and exhaust the air in the reactor;

[0010] (2) Ammonia gas is introduced into the reactor according to the required hydroxylamine ratio, followed by hydrogen gas. Then the temperature is raised to the required reaction temperature, and the reaction is carried out under stirring to obtain the amination product.

[0011] (3) The above reaction product is subjected to vacuum distillation and filtered to obtain a viscous liquid. The viscous liquid is then reacted with acid to obtain an oligomeric organic ammonium salt.

[0012] Furthermore, in the method for preparing an oligomeric organic ammonium salt, the solvent is one or a combination of cyclohexane, tert-butanol, toluene, and tetrahydrofuran.

[0013] The method for preparing an oligomeric organic ammonium salt, wherein the active metal component in the catalyst is one or a combination of two of Ni and Co, and the weight of the active component accounts for 40% to 60% of the total weight of the catalyst.

[0014] In the preparation method of the oligomeric organic ammonium salt, the amount of catalyst added accounts for 10wt% to 30wt% of the amount of raw materials added.

[0015] The method for preparing an oligomeric organic ammonium salt uses one or more combinations of Na2CO3, NaHCO3, NaOH, and NH4Cl as the catalytic activator.

[0016] The method for preparing an oligomeric organic ammonium salt has a hydroxyl-to-amino acid ratio of 1:2 to 1:7.

[0017] The method for preparing an oligomeric organic ammonium salt involves controlling the hydrogen pressure at 0-2 MPa.

[0018] The method for preparing an oligomeric organic ammonium salt has a reaction temperature of 160~220℃.

[0019] The method for preparing an oligomeric organic ammonium salt has a reaction time of 3-7 hours.

[0020] The method for preparing an oligomeric organic ammonium salt uses one of hydrochloric acid, formic acid, acetic acid, and boric acid as the acid used in salt formation.

[0021] The aforementioned benzyl quaternary ammonium salt is one of benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, and benzyltriethylammonium chloride.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) It provides a clay stabilizer with a temperature resistance of up to 300℃. The self-made oligomeric organic ammonium salt contains a double benzene ring structure and polyether segments, which effectively prevents water molecules from entering the clay layer and improves the temperature resistance; (2) It provides a clay stabilizer with excellent anti-swelling performance. When the amount of the clay stabilizer is 0.1%, the anti-swelling rate can reach more than 85%; (3) In the preparation method of oligomeric organic ammonium salt, an activator is introduced to improve the catalytic effect of the catalyst and effectively improve the reaction conversion rate. Detailed Implementation

[0023] The present invention will now be described in detail with reference to embodiments and comparative examples. Example 1

[0024] 50.0 g of bisphenol A polyoxyethylene ether (containing 8 ethylene oxide chains), 100.0 g of tetrahydrofuran, 7.5 g of catalyst (Ni content 40wt%), and 0.5 g of NaHCO3 were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:5, followed by the introduction of 1.0 MPa hydrogen. The reactor was slowly heated to 190℃ and reacted at a constant temperature of 700 rpm for 4 h with stirring. The resulting product was subjected to vacuum distillation at 100℃ and filtered; the filtrate was the reaction product BPN-1. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of formic acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0025] Weigh 1.8 g of self-made oligomeric organic ammonium salt, 9.0 g of benzyltrimethylammonium chloride, 2.4 g of KCl and 31.8 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-1. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 2

[0026] 50.0 g of bisphenol A polyoxyethylene ether (containing 8 ethylene oxide chains), 100.0 g of tetrahydrofuran, 7.5 g of catalyst (Ni content 50 wt%), and 0.5 g of NaHCO3 were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:5, followed by the introduction of 1.5 MPa hydrogen. The reactor was slowly heated to 190℃ and reacted at a constant temperature of 700 rpm for 4 h with stirring. The resulting product was subjected to vacuum distillation at 100℃ and filtered; the filtrate was the reaction product BPN-2. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of formic acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0027] Weigh 1.8 g of self-made oligomeric organic ammonium salt, 9.0 g of benzyltrimethylammonium chloride, 2.4 g of KCl and 31.8 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-2. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 3

[0028] 50.0 g of bisphenol A polyoxyethylene ether (containing 8 ethylene oxide chains), 100.0 g of tetrahydrofuran, 10 g of catalyst (Ni content 60wt%), and 0.5 g of Na2CO3 were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:5, followed by the introduction of 1.5 MPa hydrogen. The reactor was slowly heated to 200℃ and reacted at a constant temperature of 700 rpm for 5 h with stirring. The resulting product was subjected to vacuum distillation at 100℃ and filtered; the filtrate was the reaction product BPN-3. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of formic acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0029] Weigh 1.8 g of self-made oligomeric organic ammonium salt, 9.0 g of benzyltrimethylammonium chloride, 2.4 g of KCl and 31.8 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-3. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 4

[0030] 50.0 g of bisphenol A polyoxyethylene ether (containing 10 ethylene oxide chains), 100.0 g of tert-butanol, 10 g of catalyst (Ni content 50 wt%), and 0.5 g of Na₂CO₃ were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:6, followed by the introduction of 1.5 MPa hydrogen. The reactor was slowly heated to 200 °C and reacted at a constant temperature of 700 rpm for 5 h with stirring. The resulting product was subjected to vacuum distillation at 100 °C and filtered; the filtrate was the reaction product BPN-4. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of acetic acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0031] Weigh 1.5 g of self-made oligomeric organic ammonium salt, 9.0 g of benzyltrimethylammonium chloride, 2.4 g of KCl and 32.1 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-4. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 5

[0032] 50.0 g of bisphenol A polyoxyethylene ether (containing 10 ethylene oxide chains), 100.0 g of tert-butanol, 7.5 g of catalyst (Co content 40 wt%), and 0.5 g of Na₂CO₃ were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:6, followed by the introduction of 2.0 MPa hydrogen. The reactor was slowly heated to 210 °C and reacted at a constant temperature of 700 rpm for 5 h with stirring. The resulting product was subjected to vacuum distillation at 100 °C and filtered; the filtrate was the reaction product BPN-5. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of acetic acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0033] Weigh 1.5 g of self-made oligomeric organic ammonium salt, 11.0 g of benzyltrimethylammonium bromide, 2.4 g of KCl and 32.1 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-5. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 6

[0034] Bisphenol A polyoxyethylene ether (containing 10 ethylene oxide chains), 100.0 g tert-butanol, 7.5 g catalyst (Co content 50 wt%), and 0.5 g NH4Cl were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:6, followed by the introduction of 2.0 MPa hydrogen. The reactor was slowly heated to 220℃ and reacted at a constant temperature of 700 rpm for 5 h with stirring. The resulting product was subjected to vacuum distillation at 100℃ and filtered; the filtrate was the reaction product BPN-6. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of acetic acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0035] Weigh 1.5 g of self-made oligomeric organic ammonium salt, 11.0 g of benzyltrimethylammonium bromide, 2.4 g of KCl and 32.1 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-6. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 7

[0036] Bisphenol A polyoxyethylene ether (containing 12 ethylene oxide chains), 100.0 g toluene, 5.0 g catalyst (Co content 60 wt%), and 0.5 g NH4Cl were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:7, followed by the introduction of 1.5 MPa hydrogen. The reactor was slowly heated to 220℃ and reacted at a constant temperature of 700 rpm for 6 h with stirring. The resulting product was subjected to vacuum distillation at 100℃ and filtered; the filtrate was the reaction product BPN-7. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of boric acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0037] Weigh 1.3 g of self-made oligomeric organic ammonium salt, 10.0 g of benzyltriethylammonium chloride, 2.4 g of KCl and 31.3 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-7. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 8

[0038] Bisphenol A polyoxyethylene ether (containing 12 ethylene oxide chains), 100.0 g toluene, 7.5 g catalyst (Ni content 50 wt%), and 0.5 g NH4Cl were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:7, followed by the introduction of 1.5 MPa hydrogen. The reactor was slowly heated to 210 °C and reacted at a constant temperature of 700 rpm for 6 h with stirring. The resulting product was subjected to vacuum distillation at 100 °C and filtered; the filtrate was the reaction product BPN-8. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of boric acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0039] Weigh 1.3 g of self-made oligomeric organic ammonium salt, 10.0 g of benzyltriethylammonium chloride, 2.4 g of KCl and 31.3 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-8. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2. Example 9

[0040] Bisphenol A polyoxyethylene ether (containing 12 ethylene oxide chains), 100.0 g toluene, 10.0 g catalyst (Co content 50 wt%), and 0.5 g NH4Cl were weighed into a batch high-pressure reactor, and the reactor was tightened. The reactor was purged three times with 0.5 MPa nitrogen to remove air. Ammonia was introduced into the reactor at a hydroxyl to ammonia ratio of 1:7, followed by the introduction of 2.0 MPa hydrogen. The reactor was slowly heated to 210℃ and reacted at a constant temperature of 700 rpm for 6 h with stirring. The resulting product was subjected to vacuum distillation at 100℃ and filtered; the filtrate was the reaction product BPN-9. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion and selectivity were calculated. The results are shown in Table 1. A certain amount of boric acid was added to the product to adjust the pH to 7, thus preparing the oligomeric organic ammonium salt.

[0041] Weigh 1.3 g of self-made oligomeric organic ammonium salt, 10.0 g of benzyltriethylammonium chloride, 2.4 g of KCl and 31.3 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, labeled as sample-9. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2.

[0042] Comparative Example 1

[0043] In Example 1, the activator NaHCO3 was not introduced into the raw materials, and the remaining reaction procedures were the same as in Example 1. The amine value of the product was determined by hydrochloric acid titration, and the reaction conversion rate and selectivity were calculated. The results are shown in Table 1. A certain amount of formic acid was added to the product to adjust the pH to 7, thus obtaining the oligomeric organic ammonium salt.

[0044] Weigh 1.8 g of self-made oligomeric organic ammonium salt, 9.0 g of benzyltrimethylammonium chloride, 2.4 g of KCl and 31.8 g of H2O into a beaker and stir thoroughly to obtain a clay stabilizer. Prepare a 0.1% aqueous solution, which is recorded as Comparative Example-1. The evaluation results of its anti-swelling performance, temperature resistance and water washability are shown in Table 2.

[0045] Procedure for determining amine value using hydrochloric acid titration:

[0046] (1) Determination of total amine value:

[0047] Weigh approximately 1g of the sample into a 250mL Erlenmeyer flask (accurate to 0.1mg), add 50mL of ethanol, and heat for 1 minute to prevent NH4+ from entering the flask. + To remove interference, cool to room temperature. Add 5 drops of bromophenol blue indicator and titrate with 0.1 mol / L HCl to a yellow endpoint while stirring. Calculate the total amine value A1 based on the volume V1 of HCl consumed, as shown in Equation 1.

[0048] A1 = C1 * V1 / M1 (Equation 1)

[0049] In the formula: A1: total amine value of the product, mmol / g; M1: sample mass, g; V1: volume of hydrochloric acid consumed, mL; C1: concentration of hydrochloric acid used for titration, mol / L.

[0050] (2) Determination methods for primary, secondary and tertiary amine groups

[0051] Weigh out two portions of approximately 1.0 g each and place them in 250 mL Erlenmeyer flasks (dissolve the solid first if it is solid), label them S and T, add 50 mL of CHCl3, and heat for 1 minute to prevent NH4+ from entering. + To eliminate interference, cool to room temperature. Add 3 mL of salicylaldehyde to sample S, let stand for 30 minutes, add 1 mL of bromophenol blue indicator, and titrate with 0.1 mol / L HCl to a yellow endpoint while stirring. Calculate the sum of the secondary and tertiary amine values ​​based on the volume of HCl consumed, V2, as shown in Equation 2. Add 3 mL of phenyl isothiocyanate to sample T, let stand for 30 minutes, add 1 mL of bromophenol blue indicator, and titrate with 0.1 mol / L HCl to a yellow endpoint while stirring. Calculate the tertiary amine value based on the volume of HCl consumed, V3, as shown in Equation 3.

[0052] A2 = C1 * V2 / M2 (Equation 2)

[0053] A3 = C1 * V1 / M3 (Equation 3)

[0054] In the formula: A2: the sum of secondary and tertiary amines, mmol / g; A3: the value of tertiary amine, mmol / g; M2: sample mass, g; M3: sample mass, g.

[0055] The formulas for calculating the secondary amine value and the primary amine value are shown in Equations 4 and 5, respectively:

[0056] A4 = A2 - A3 (Equation 4)

[0057] A5 = A1 - A2 (Equation 5)

[0058] In the formula: A4: secondary amine value, mmol / g; A5: tertiary amine value, mmol / g.

[0059] (3) Calculation method of reaction conversion rate and selectivity

[0060] The formulas for calculating the reaction conversion rate and selectivity are shown in Equations 6 and 7, respectively:

[0061]

[0062] Evaluation method for anti-swelling performance:

[0063] The anti-swelling rate test was conducted according to the "SY / T5971-2016 Performance Evaluation Method for Clay Stabilizers for Water Injection". The steps are as follows: Weigh 0.5g of sodium bentonite, add it to a 10mL centrifuge tube, add deionized water to the 10mL mark, shake thoroughly, let stand at room temperature for 2 hours, put it into a centrifuge, and centrifuge at 1500r / min for 15 minutes. Read the volume V2 of sodium bentonite in water. Use the same steps but replace water with a clay stabilizer aqueous solution of a certain concentration to measure the volume V1 of the soil after centrifugation. Use kerosene instead of water to measure the volume V0 of the soil. The anti-swelling rate calculation formula is as follows:

[0064]

[0065] In the formula: or — 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 water, mL.

[0066] Evaluation method for anti-swelling performance after aging at 300℃:

[0067] A high-temperature swelling resistance test was conducted according to the "QS / H125-2017 Technical Requirements for Clay Stabilizers". 3.00g of bentonite powder, accurate to 0.01g, was weighed and placed into a high-temperature, high-pressure sealed reactor. 60mL of a 4% clay stabilizer solution was added, and the mixture was thoroughly shaken and placed in an oven at 300±2℃ for 24 hours, then cooled to room temperature. The entire clay stabilizer mixture from the high-temperature, high-pressure sealed reactor was transferred to a 100mL beaker, thoroughly shaken, and 10mL was quickly transferred to a glass centrifuge tube. The tube was then placed in a centrifuge with an automatic balancing function and centrifuged at 1500r / min for 15min. The swelling volume V1 of the bentonite was recorded. The swelling resistance calculation formula is as follows:

[0068]

[0069] In the formula: V0 is the expansion volume of bentonite in kerosene; V1 is the expansion volume of bentonite in the clay stabilizer aqueous solution; V2 is the expansion volume of bentonite in water.

[0070] Methods for evaluating water washability:

[0071] Pour off the supernatant from the centrifuge tube after high-temperature aging and centrifugation, add deionized water to 10 mL, stir thoroughly, let stand for 2 hours, and then centrifuge at 1500 r / min for 15 min. Finally, read the final volume V1 of the bentonite in the centrifuge tube. ′ The formula for calculating the wash resistance rate is as follows:

[0072]

[0073] In the formula: V1 is the swelling volume of bentonite in the clay stabilizer aqueous solution, mL; V1′ is the swelling volume of bentonite after washing with water, mL; V2 is the swelling volume of bentonite in clean water, mL.

[0074] Table 2 Performance evaluation results of the examples and comparative samples

[0075]

[0076] As can be seen from the above embodiments, the clay stabilizer preparation method provided by the present invention is simple to operate, and the reaction performance is effectively improved by introducing an activator. Moreover, the clay stabilizer obtained has excellent temperature resistance and outstanding anti-swelling effect. When the amount added is only 0.1%, the anti-swelling rate can reach more than 85%, the temperature resistance reaches 300℃, and the water washing resistance reaches 100%.

Claims

1. A high-temperature resistant and efficient clay stabilizer, characterized in that... It contains oligomeric organic ammonium salts, benzyl quaternary ammonium salts, and the inorganic salt KCl, wherein the structural formula of the oligomeric organic ammonium salt is: or or or ， Where n = 8~16.

2. The high-temperature resistant and efficient clay stabilizer according to claim 1, characterized in that... The molar ratio of oligomeric organic ammonium salt, benzyl quaternary ammonium salt and KCl in the composition is 1:20:12 to 1:30:

18.

3. The high-temperature resistant and efficient clay stabilizer according to claim 1 or 2, characterized in that... The preparation method of the oligomeric organic ammonium salt includes the following steps: (1) Add bisphenol A polyoxyethylene ether, solvent, catalyst and activator to the reactor, purge the reactor with nitrogen gas to replace the air inside the reactor; the amount of catalyst added is 10wt%~30wt% of the amount of raw materials added; (2) Ammonia gas is introduced into the reactor at a hydroxylamine ratio of 1:2 to 1:7, followed by hydrogen gas. Then the temperature is raised to the required reaction temperature and the reaction is carried out under stirring to obtain the amination product. (3) The above reaction product is subjected to vacuum distillation and filtered to obtain a viscous liquid. The viscous liquid is then reacted with acid to obtain an oligomeric organic ammonium salt.

4. The high-temperature resistant and efficient clay stabilizer according to claim 3, characterized in that... The solvent is one or a combination of cyclohexane, tert-butanol, toluene, and tetrahydrofuran.

5. The high-temperature resistant and efficient clay stabilizer according to claim 3, characterized in that... The active metal component in the catalyst is one or a combination of two of Ni and Co, and the active component accounts for 40% to 60% of the total weight of the catalyst.

6. The high-temperature resistant and efficient clay stabilizer according to claim 3, characterized in that... The activator is one or a combination of Na2CO3, NaHCO3, NaOH and NH4Cl.

7. The high-temperature resistant and efficient clay stabilizer according to claim 3, characterized in that... The pressure of the hydrogen gas introduced is 0~2MPa.

8. The high-temperature resistant and efficient clay stabilizer according to claim 3, characterized in that... The reaction temperature is 160~220℃, and the reaction time is 3~7h.

9. The high-temperature resistant and efficient clay stabilizer according to claim 3, characterized in that... The acid used in the reaction is one of hydrochloric acid, formic acid, acetic acid, or boric acid.

10. The high-temperature resistant and efficient clay stabilizer according to claim 1 or 2, characterized in that... The benzyl quaternary ammonium salt is one of benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, and benzyltriethylammonium chloride.

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