Application of tetramethylammonium chloride recovery solution in clay anti-swelling agent

Abstract

The application discloses application of tetramethylammonium chloride recovery liquid in a clay anti-swelling agent and belongs to the technical field of anti-swelling agent preparation. The tetramethylammonium chloride recovery liquid is applied in the clay anti-swelling agent, so that the tetramethylammonium chloride waste liquid can be fully utilized, the environment is protected, the obtained anti-swelling agent has the advantages of small dosage, good performance, low cost and good economic benefits.

Description

Technical Field

[0001] This invention belongs to the field of anti-swelling agent preparation technology, and particularly relates to the application of a tetramethylammonium chloride recovery solution in clay anti-swelling agents. Background Technology

[0002] Tetramethylammonium hydroxide (TMAH) aqueous solution is widely used in the photolithography process of integrated circuits, LCD panels, and printed circuit boards, and is known as the developer. Due to its unique structure, TMAH is a major contributor to ammonia nitrogen in wastewater, posing challenges to its treatment and introducing numerous environmental risks. Typically, after use, the developer undergoes acid neutralization and other treatments, resulting in a waste liquid containing 10% tetramethylammonium chloride (TMACL). Direct discharge of TMACL waste liquid inevitably damages the environment and wastes TMACL resources. Recycling and reusing the tetramethylammonium chloride waste liquid can not only improve the utilization rate of TMACL and reduce costs, but also mitigate environmental damage.

[0003] Fracturing is a technique that uses pressure to open up the formation, creating fractures, and then uses proppant to support these fractures. This improves the conductivity of the oil and gas reservoir, reducing fluid flow resistance and increasing production and injection capacity. The fracturing fluid used in the fracturing process plays a crucial role in transmitting pressure, creating formation fractures, and transporting proppant along the opened fractures. During oilfield development, clay minerals are prone to expansion and migration. To reduce the impact on reservoir permeability, clay stabilizers need to be added to the fracturing fluid. Existing anti-swelling agents are diverse, mainly inorganic salt-based or polymer-based. Inorganic salt-based anti-swelling agents have poor anti-swelling effects and are not resistant to flushing, affecting fracturing efficiency. While polymer-based anti-swelling agent systems are effective, their effectiveness is limited by molecular weight. Excessively large molecular weights result in poor porosity in low-permeability reservoirs, while small molecular weights shorten the anti-swelling period. Furthermore, their high cost makes them unacceptable to the market. Therefore, there is a need to develop anti-swelling agents with high anti-swelling rates at low dosages, which also aligns with the development trend of efficient and low-cost oilfield treatment agents. Summary of the Invention

[0004] This invention provides an application of tetramethylammonium chloride recovery liquid in clay anti-swelling agents. By applying tetramethylammonium chloride recovery liquid to clay anti-swelling agents, this invention not only makes full use of tetramethylammonium chloride waste liquid and protects the environment, but also produces an anti-swelling agent with low dosage, good performance, and low cost, resulting in good economic benefits.

[0005] To achieve the above objectives, the present invention provides the application of tetramethylammonium chloride recovery solution in clay anti-swelling agents, wherein the tetramethylammonium chloride recovery solution comprises 40wt% to 70wt% tetramethylammonium chloride, 2000 to 4000 ppb sodium ions, 100000 to 200000 ppb potassium ions, 1000 to 2000 ppb calcium ions, 300 to 1000 ppb iron ions, and the balance being water.

[0006] Preferably, the clay anti-swelling agent comprises, by weight parts: tetramethylammonium chloride recovery liquid 100 parts, organic ammonium salt 8-20 parts, inorganic salt 10-20 parts, and water 10-35 parts.

[0007] Preferably, the organic ammonium salt comprises one or more of benzyltrimethylammonium chloride, 2-chloroethyltrimethylammonium chloride, glycidyltrimethylammonium chloride, and 3-chloro-2-hydroxypropyltrimethylammonium chloride.

[0008] Preferably, the inorganic salt is one or more of sodium chloride, calcium chloride, magnesium chloride, and ammonium chloride.

[0009] Preferably, the method for preparing the clay anti-swelling agent is:

[0010] 1) mixing the organic ammonium salt with water to obtain an organic ammonium salt solution;

[0011] 2) mixing the tetramethylammonium chloride recovery liquid, the organic ammonium salt solution, and the inorganic salt, stirring until dissolved, and adjusting the pH to 6-8 to obtain the clay anti-swelling agent.

[0012] Preferably, the solution used to adjust the pH is hydrochloric acid.

[0013] Preferably, the tetramethylammonium chloride recovery liquid is obtained after eluting tetramethylammonium hydroxide developing solution with hydrochloric acid.

[0014] Preferably, the anti-swelling rate of the clay anti-swelling agent is ≥80%, and the long-acting anti-swelling performance is ≥86%.

[0015] Preferably, the addition amount of the clay anti-swelling agent is 0.5wt%-2wt%.

[0016] Compared with the prior art, the advantages and positive effects of the present application are:

[0017] The present application applies tetramethylammonium chloride recovery liquid in the clay anti-swelling agent, the recovery liquid is rich in tetramethylammonium chloride, and trace amounts of metal cation components such as Na + , K + , Ca 2+ , Fe 3+ , etc.

[0018] Meanwhile, the application makes full use of the tetramethylammonium chloride waste liquid, protects the environment, has low cost and good economic benefits. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The swelling volume after centrifugation of Example 1 and Comparative Example 1 is shown; wherein Figure 1 The left graph is Example 1, and the right graph is Comparative Example 1. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the application.

[0021] The application provides application of tetramethylammonium chloride recovery liquid in clay anti-swelling agent, the tetramethylammonium chloride recovery liquid includes 40wt% to 70wt% tetramethylammonium chloride, 2000 to 4000ppb sodium ion, 100000 to 200000ppb potassium ion, 1000 to 2000ppb calcium ion, 300 to 1000ppb iron ion and the balance of water.In the application, the tetramethylammonium chloride recovery liquid is obtained after hydrochloric acid elution of tetramethylammonium hydroxide developing solution.

[0022] The clay minerals such as montmorillonite in the formation can swell in water, and due to lattice substitution, the electrical valence of the crystal structure is unbalanced, and a certain amount of cations need to be combined on the surface to balance the electrical valence, and the cations carried by the recovered tetramethylammonium chloride solution just meet the requirement, which can neutralize the negative electricity on the surface of clay through adsorption, and can also be adsorbed between the crystal layers of clay, reduce the electricity between the surface crystal layers, and the thickness of the double electric layer and zeta potential on the surface of clay, thereby reducing the repulsion between them, and preventing the occurrence of clay swelling.

[0023] In the application, the clay anti-swelling agent preferably includes, by weight: 100 parts of tetramethylammonium chloride recovery liquid, 8 to 20 parts of organic ammonium salt, 10 to 20 parts of inorganic salt and 10 to 35 parts of water.In the application, the organic ammonium salt preferably includes one or more of benzyltrimethylammonium chloride, 2-chloroethyltrimethylammonium chloride, epoxypropyltrimethylammonium chloride and 3-chloro-2-hydroxypropyltrimethylammonium chloride.In the application, after the above-mentioned organic ammonium salt is dissolved in water, the surface active cations are dissociated, can exchange the cations on the surface of the clay crystal layer, the negative charge on the surface of the clay is adsorbed and neutralized, the electrostatic attraction is increased, the repulsion between the crystal layers is reduced, and the anti-swelling effect is achieved.

[0024] In the present application, the inorganic salt is preferably one or more of sodium chloride, calcium chloride, magnesium chloride and ammonium chloride. In the present application, the above-mentioned inorganic salt can be dissociated in water, and when the salt concentration is high, the cations generated by dissociation can effectively compress the thickness of the diffuse double layer on the surface of clay, reduce the double layer repulsion between the clay sheet structure, and inhibit the swelling of clay.

[0025] The tetramethylammonium chloride aqueous solution is the main component in the tetramethylammonium chloride recovery liquid, and the recovery liquid is rich in Na + , K + , Ca 2+ , Fe 3+ and other metal cation components after purification. If further purification is required, not only certain technical difficulties need to be overcome, but also a large amount of energy consumption and cost increase are required. In the present application, the residual cation impurities are fully utilized to improve the utilization rate of TMACL and reduce the cost, and the damage to the environment is reduced. On this basis, a part of cationic quaternary ammonium salt and inorganic salt anti-swelling agent is added to obtain a formula type clay stabilizer. The positive groups on the clay anti-swelling agent can be exchanged and adsorbed with low-valent cations between the crystal layers and on the surface, and the exchange and adsorption with hydrated cations are inhibited, so that the clay no longer swells due to the adsorption of hydrated cations, thereby the long-acting anti-swelling performance of the clay stabilizer is improved, and the swelling and migration of clay minerals are reduced.

[0026] In the present application, the preparation method of the clay anti-swelling agent is preferably:

[0027] 1) mixing the organic ammonium salt with water to obtain an organic ammonium salt solution;

[0028] 2) mixing the tetramethylammonium chloride recovery liquid, the organic ammonium salt solution and the inorganic salt, stirring until dissolved, and adjusting the pH to 6-8 to obtain the clay anti-swelling agent.

[0029] In the present application, the solution used for adjusting the pH is preferably hydrochloric acid.

[0030] In the present application, the anti-swelling rate of the clay anti-swelling agent is preferably ≥80%, and the long-acting anti-swelling performance is preferably ≥86%.

[0031] In the present application, the addition amount of the clay anti-swelling agent is preferably 0.5wt%-2wt%.

[0032] In order to further illustrate the present application, the technical solutions provided by the present application are described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present application.

[0033] The tetramethylammonium chloride recovery liquid used in Examples 1 to 5 and Comparative Examples 1 to 3 is derived from a purified waste developer solution, which is treated by first filtering the waste developer solution to remove photoresist and other impurities, then adsorbing the TMAH waste solution with a resin column, and then desorbing the TMAH as tetramethylammonium chloride (10%) with HCl, which is then concentrated to form the tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid is 50%, the sodium ion content is 3169 ppb, the potassium ion content is 155400 ppb, the calcium ion content is 1111 ppb, and the iron ion content is 523 ppb).

[0034] Example 1

[0035] 9.4 g of benzyltrimethylammonium chloride was mixed with 15.6 g of water to form a benzyltrimethylammonium chloride solution. 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid was 50%) was weighed into a beaker, and the above benzyltrimethylammonium chloride solution and 10 g of magnesium chloride were slowly added under stirring, respectively. The stirring was continued for 20 min, and hydrochloric acid was added to adjust the pH of the mixture to 6.0, to obtain a formula type anti-swelling agent 1.

[0036] Example 2

[0037] 9.4 g of benzyltrimethylammonium chloride was mixed with 15.6 g of water to form a benzyltrimethylammonium chloride solution. 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid was 50%) was weighed into a beaker, and the above benzyltrimethylammonium chloride solution and 10 g of sodium chloride were slowly added under stirring, respectively. The stirring was continued for 20 min, and hydrochloric acid was added to adjust the pH of the mixture to 6.0, to obtain a formula type anti-swelling agent 2.

[0038] Example 3

[0039] 9.4 g of benzyltrimethylammonium chloride was mixed with 15.6 g of water to form a benzyltrimethylammonium chloride solution. 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid was 50%) was weighed into a beaker, and the above benzyltrimethylammonium chloride solution and 15 g of calcium chloride were slowly added under stirring, respectively. The stirring was continued for 20 min, and hydrochloric acid was added to adjust the pH of the mixture to 6.0, to obtain a formula type anti-swelling agent 3.

[0040] Example 4

[0041] 9 g of 2-chloroethyltrimethylammonium chloride was mixed with 16 g of water to form a 2-chloroethyltrimethylammonium chloride solution. 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid was 50%) was weighed into a beaker, and the above 2-chloroethyltrimethylammonium chloride solution and 10 g of ammonium chloride were slowly added under stirring, respectively. The stirring was continued for 20 min, and hydrochloric acid was added to adjust the pH of the mixture to 8.0, to obtain a formula type anti-swelling agent 4.

[0042] Example 5

[0043] Take 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid is 50%) in a beaker, slowly add 10 g of magnesium chloride under stirring, continue stirring for 20 min, and add hydrochloric acid to adjust the pH of the mixture to 6.0 to obtain formula anti-swelling agent 6.

[0044] Comparative Example 1

[0045] The difference from Example 1 is that no organic ammonium salt is added, and the rest of the operations are exactly the same as in Example 1, and the specific operation is as follows:

[0046] Take 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid is 50%) in a beaker, slowly add 10 g of magnesium chloride under stirring, continue stirring for 20 min, and add hydrochloric acid to adjust the pH of the mixture to 6.0 to obtain formula anti-swelling agent 6.

[0047] Comparative Example 2

[0048] The difference from Example 1 is that no inorganic salt is added, and the rest of the operations are exactly the same as in Example 1, and the specific operation is as follows:

[0049] Take 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid is 50%) in a beaker, slowly add 25 g of benzyltrimethylammonium chloride solution with a mass concentration of 60% under stirring, continue stirring for 20 min, and add hydrochloric acid to adjust the pH of the mixture to 6.0 to obtain formula anti-swelling agent 7.

[0050] Comparative Example 3

[0051] The difference from Example 1 is that the inorganic salt is replaced by potassium chloride, and the rest of the operations are exactly the same as in Example 1, and the specific operation is as follows:

[0052] Take 100 g of tetramethylammonium chloride recovery liquid (the mass concentration of the tetramethylammonium chloride recovery liquid is 50%) in a beaker, slowly add 25 g of benzyltrimethylammonium chloride solution with a mass concentration of 60% and 10 g of potassium chloride under stirring, continue stirring for 20 min, and add hydrochloric acid to adjust the pH of the mixture to 6.0 to obtain formula anti-swelling agent 8.

[0053] Comparative Example 4

[0054] The difference from Example 1 is that no tetramethylammonium chloride recovery solution is added, and the total ammonium content of the 60% benzyltrimethylammonium chloride solution is the same as that of Example 1, and the rest of the operations are exactly the same as those of Example 1, and the specific operation is as follows:

[0055] 84 g of a 60% benzyltrimethylammonium chloride solution and 10 g of magnesium chloride are weighed, and stirring is continued for 20 min. Hydrochloric acid is added to adjust the pH of the mixture to 6.0 to obtain Formula Anti-swelling Agent 9.

[0056] Performance test

[0057] The bentonite is sodium-based bentonite, and the drilling mud suspension has high rheological properties and thixotropic properties.

[0058] 0.5 g of the anti-swelling agent of each example and comparative example is weighed, and water is added to 100 g to obtain an anti-swelling agent with a mass concentration of 0.5%.

[0059] 0.50 g of sodium bentonite (accurate to 0.01 g) is weighed into a 10 mL centrifuge tube, 10 mL of the above-mentioned 0.5% anti-swelling agent is added, and it is shaken well and placed at room temperature for 2 h. It is loaded into a centrifuge, and centrifugal separation is carried out at a speed of 1500 r / min for 15 min. The swelling volume of sodium bentonite in the clay stabilizer solution is measured and recorded as V1 (wherein the swelling effect of Example 1 and Comparative Example 1 after centrifugation in the centrifuge is shown in Figure 1 0.50 g of sodium bentonite (accurate to 0.01 g) is weighed into a 10 mL centrifuge tube, 10 mL of the above-mentioned 0.5% anti-swelling agent is added, and it is shaken well and placed at room temperature for 2 h. It is loaded into a centrifuge, and centrifugal separation is carried out at a speed of 1500 r / min for 15 min. The swelling volume of sodium bentonite in the clay stabilizer solution is measured and recorded as V1 (wherein the swelling effect of Example 1 and Comparative Example 1 after centrifugation in the centrifuge is shown in

[0060] 2 g of the anti-swelling agent of each example and comparative example is weighed, and water is added to 100 g to obtain a 2% solution. 2% water washing resistance test is carried out. After sodium bentonite is soaked in the anti-swelling agent solution, the anti-swelling agent will be adsorbed on the surface of the sodium bentonite. After washing with test water, the clay stabilizer gradually loses its effectiveness. The long-term anti-swelling performance of the anti-swelling agent is evaluated by measuring the swelling volume of sodium bentonite after washing three times, and the results are shown in Table 1.

[0061] Table 1 Anti-swelling performance test

[0062]

[0063]

[0064] As shown in Table 1, the anti-swelling agents prepared in the embodiments of the present invention have better anti-swelling effects, long-term anti-swelling performance, and stable cycle performance compared with those in the comparative examples. Among them, anti-swelling agent 1 has the best anti-swelling effect. In comparative example 1, the anti-swelling effect was poor because no organic ammonium salt was added to the tetramethylammonium chloride compound. As a cationic clay stabilizer, the organic ammonium salt has good compatibility with other fracturing fluids and acidizing fluids, which can improve the anti-swelling performance of the clay stabilizer. In comparative example 3, the solubility of the inorganic salt potassium chloride is 34%, and it is immiscible with the 50% tetramethylammonium chloride aqueous solution, so it is not possible to develop an anti-swelling agent formulation. In comparative example 4, the effects of using benzyltrimethylammonium chloride alone and the combination of tetramethylammonium chloride and benzyltrimethylammonium chloride are similar. However, the price of benzyltrimethylammonium chloride alone as a clay stabilizer is slightly higher. Since the recovery liquid itself is a profitable business, the clay stabilizer obtained by recovering tetramethylammonium chloride and combining it with benzyltrimethylammonium chloride has a lower cost advantage.

[0065] Figure 1 The expansion volumes of the clay stabilizer after centrifugation in the centrifuges for Example 1 and Comparative Example 1 are shown respectively. It can be clearly seen that the expansion volume of the clay stabilizer in Example 1 is about 9.5, which shows a high level of anti-swelling performance, while the anti-swelling effect of the clay stabilizer in Comparative Example 1 is weaker.

[0066] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. The application of tetramethylammonium chloride recovery solution in clay anti-swelling agents, characterized in that, The tetramethylammonium chloride recovery solution comprises 40wt%~70wt% tetramethylammonium chloride, 2000~4000ppb sodium ions, 100000~200000ppb potassium ions, 1000~2000ppb calcium ions, 300~1000ppb iron ions, and the balance being water. By weight, the clay anti-swelling agent comprises: 100 parts of tetramethylammonium chloride recovery solution, 8-20 parts of organic ammonium salt, 10-20 parts of inorganic salt, and 10-35 parts of water; The organic ammonium salt includes one or more of benzyltrimethylammonium chloride, 2-chloroethyltrimethylammonium chloride, glycidyltrimethylammonium chloride, and 3-chloro-2-hydroxypropyltrimethylammonium chloride; The inorganic salt is one or more of sodium chloride, calcium chloride, magnesium chloride, and ammonium chloride.

2. The application according to claim 1, characterized in that, The method for preparing the clay anti-swelling agent is as follows: 1) Mixing organic ammonium salt with water to obtain an organic ammonium salt solution; 2) Mix the tetramethylammonium chloride recovery solution, organic ammonium salt solution and inorganic salt, stir until dissolved, and adjust the pH to 6-8 to obtain clay anti-swelling agent.

3. The application according to claim 2, characterized in that, The solution used to adjust the pH is hydrochloric acid.

4. The application according to claim 1, characterized in that, The tetramethylammonium chloride recovery solution is obtained by eluting tetramethylammonium hydroxide developer with hydrochloric acid.

5. The application according to claim 1, characterized in that, The clay anti-swelling agent has an anti-swelling rate of ≥80% and a long-lasting anti-swelling performance of ≥86%.

6. The application according to claim 1, characterized in that, The amount of the clay anti-swelling agent added is 0.5wt%~2wt%.

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