Inhibitor suitable for soluble alkaline salt scale and preparation method thereof

Abstract

The invention discloses a soluble alkaline salt scale inhibitor and a preparation method thereof, and belongs to the technical field of oilfield chemistry. The soluble alkaline salt scale inhibitor is prepared from amphiphilic modified graphene oxide, a surfactant, inorganic salt and deionized water, the amphiphilic modified graphene oxide contains a large amount of carboxyl groups, sulfonic acid groups, hydroxyl groups and the like, and has good metal ion chelating property; meanwhile, through the hydrophobic association effect and hydrogen-bond interaction between modified graphene grafted long carbon chains, the bonding probability between sodium ions of the soluble saline-alkali salt and bicarbonate radicals, carbonate radicals and chloride ions is further weakened, and through the synergistic effect of the amphiphilic modified graphene oxide, the surfactant and the inorganic salt, the salt scale inhibition effect is further improved; the method is especially suitable for soluble alkali salt water quality conditions of high temperature, high alkali and high salinity, can solve the problems of oilfield water injection, fracturing flowback strata and wellbore salt deposition, and has a good popularization prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of oilfield exploitation, and in particular relates to a soluble alkaline salt scale inhibitor and a preparation method thereof. Background Art

[0002] Due to the high mineralization of formation water in high-salt wells, a large amount of salt scale is generated during the production process of oil wells, resulting in a significant increase in maintenance costs, a significant decrease in production, a deterioration in the effect of acid fracturing, high squeezing pressure, and a short effective period, causing huge economic losses. Salt inhibitors are a method of injecting chemical agents into the well to inhibit salt formation. This method has attracted widespread attention due to its simple operation, low cost and high efficiency, and does not affect the quality and production of crude oil. Salt scale inhibitors have been developed for soluble salts (mainly sodium chloride) and insoluble salt scale (calcium carbonate, barium sulfate, etc.), such as phosphates, carboxylic acid homopolymers, and green and environmentally friendly polyaspartic acid PASP and polyepoxysuccinic acid PESA, which can all play a good role in scale inhibition. However, for the problem of salt formation in the formation or wellbore of high-temperature and high-mineralization formation water mainly composed of sodium carbonate and sodium bicarbonate, the chemical properties of this type of composite salt (solubility, pH, ionic bonding strength, crystal form) are different from conventional salt scale, and the conventional low-molecular-weight polyanionic scale inhibitors or salt inhibitors have limited anti-salt effects.

[0003] Through searching, the following patent disclosures related to the patent application of the present invention were found. A method for preparing a salt recrystallization inhibitor for oil and gas wells CN105462569B, a simple synthesis and use of a salt crystallization inhibitor CN106957639A: The disclosed salt crystal inhibitor is mainly aimed at the salt formation and salt prevention problem of saturated or supersaturated salt solutions mainly composed of sodium chloride, but has limited effect on the salt crystallization inhibition of salts mainly composed of sodium bicarbonate or sodium carbonate. Application of disodium EDTA as a low-temperature crystallization and precipitation inhibitor for sodium carbonate solution CN103497749B reports the preparation and application of an ELYZ-09 sodium carbonate crystallization inhibitor synthesized by ethylenediamine, hydroxyacetonitrile and isopropanol, which mainly solves the problem of crystallization and precipitation of sodium carbonate solution during transportation. It has a good anti-crystallization effect on sodium carbonate solution mainly at a lower temperature of 30°C to 10°C, but the effect on high-temperature oil reservoirs and saturated solutions of sodium carbonate / sodium bicarbonate / sodium chloride composite salts is not yet clear. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a soluble alkaline scale inhibitor and a preparation method thereof, which belongs to the field of oilfield chemical technology, can effectively dissolve the scaling of sodium carbonate, sodium bicarbonate and their composite salts, and still has a good scale inhibition effect under high temperature, high salt and alkalinity; the soluble alkaline scale inhibitor is prepared from amphiphilic modified graphene oxide TAS-GO, a surfactant, an inorganic salt and deionized water; the amphiphilic modified graphene oxide TAS-GO contains a large number of carboxyl groups, sulfonic acid groups and hydroxyl groups, etc., and has Good metal ion chelating property; at the same time, through the hydrophobic association and hydrogen bonding between the modified graphene grafted long carbon chains, the bonding probability between the soluble salt-alkali sodium ions and the bicarbonate, carbonate and chloride ions is further weakened, and the salt scale inhibition effect is further increased through the synergistic effect of amphiphilic modified graphene oxide TAS-GO, surfactants and inorganic salts. It is especially suitable for high temperature, high alkali and high mineralization soluble alkali salt water conditions, and can solve the problems of oil field water injection, fracturing flowback formation and wellbore salt deposition, and has good promotion prospects.

[0005] In order to achieve the above technical effects, the following technical solutions are adopted: A scale inhibitor suitable for soluble alkaline salts, comprising: Amphiphilic modified graphene oxide TAS-GO, surfactant, inorganic salt and water; The mass concentration of the amphiphilic modified graphene oxide TAS-GO in the inhibitor is 0.1-0.5%; The mass concentration of the surfactant in the inhibitor is 0.2 to 0.4%; The mass concentration of the inorganic salt in the inhibitor is 0.3 to 0.5%; The inorganic salt is one or more of potassium chloride and sodium chloride; The surfactant is one or more of sodium dodecylbenzene sulfonate, sodium hexadecyl sulfate, sodium hexadecyl sulfonate, sodium lauryl polyoxyethylene ether sulfate, sodium di(laureth-7) citrate, and sodium coconut oil hydroxysulfonate.

[0006] Furthermore, the structural formula of the amphiphilic modified graphene oxide TAS-GO is: .

[0007] Furthermore, the water is deionized water; the surfactant is one or more of sodium dodecylbenzene sulfonate, sodium hexadecyl sulfonate, and sodium coconut oil hydroxy sulfonate.

[0008] Furthermore, the specific preparation method of the amphiphilic modified graphene oxide TAS-GO is: Step S1: Preparation of hydrophilic modified graphene oxide AS-GO intermediate: 0.5 ~ 1.2g of graphene oxide GO is ultrasonically dispersed in 100 ~ 250 mL of deionized water for 1 ~ 2h to form a GO dispersion; 6-amino-4-hydroxy-2-naphthalenesulfonic acid AS is neutralized with 1 ~ 3mol / L sodium hydroxide solution to form an AS aqueous solution; the AS aqueous solution is continuously stirred, and the AS aqueous solution is added to the GO dispersion at a rate of 5 ~ 10mL / min, and the stirring reflux reaction is continued at 70 ~ 90°C for 8 ~ 12h; the reaction mixture is centrifuged at 4500 r / min for 30 min, and the supernatant is dried to obtain a hydrophilic modified graphene oxide AS-GO intermediate; the reaction formula of the reaction process is as follows: .

[0009] Step S2: Preparation of amphiphilic modified graphene oxide TAS-GO: The hydrophilic modified graphene oxide AS-GO intermediate obtained in step S1, the silane coupling agent, and the ethanol / water mixture are mixed and reacted at 60-80°C for 5-8 hours; then centrifuged at 4500r / min for 30 minutes, and the upper clear liquid is discarded; after washing the lower solid 2-3 times, it is dried at 80°C to obtain the amphiphilic modified graphene oxide TAS-GO; the reaction formula of the reaction process is as follows: .

[0010] Furthermore, during the reaction process of step S1, the mass ratio of graphene oxide GO to 6-amino-4-hydroxy-2-naphthalenesulfonic acid is 1:2 to 1:3.

[0011] Furthermore, the pH value of the AS aqueous solution in step S1 is 7 to 9; the drying conditions of the supernatant are: 50° C. and a vacuum degree of -0.088 MPa.

[0012] Furthermore, the pH value of the AS aqueous solution in step S1 is 7-8; the ethanol / water mixed solution in step S2 is ethanol and water in a mass ratio of 1:1; and the lower layer solid is washed with the ethanol / water mixed solution and deionized water, respectively.

[0013] Furthermore, the mass ratio of the hydrophilic modified graphene oxide AS-GO intermediate to the silane coupling agent in step S2 is 1:1-1:4; the silane coupling agent is one of dodecane silane coupling agent and hexadecane silane coupling agent.

[0014] Furthermore, the preparation method is specifically as follows: The amphiphilic modified graphene oxide TAS-GO is mixed with an inorganic salt, a surfactant and water according to the mass concentration ratio, and then heated at 30 to 50° C. and ultrasonically dispersed for 10 to 30 minutes to obtain the soluble alkaline scale inhibitor.

[0015] Furthermore, the soluble alkaline salt scale inhibitor is used in the fields of oil field water injection and fracturing backflow scale inhibition.

[0016] Beneficial effects: (1) The present invention provides a soluble alkali salt scale inhibitor, the key component of which is amphiphilic modified graphene oxide, which contains a large number of carboxyl groups, sulfonic acid groups and hydroxyl groups in its molecular structure, has good water solubility and electrostatic shielding of the mutual combination of soluble salt anions and cations, and has good metal ion chelating properties; at the same time, it also contains large-scale conjugated rings and hydrophobic long carbon chains, and through the hydrophobic association between the long carbon chains grafted on the monolithic modified graphene and the hydrogen bonding between the carboxyl groups and the hydroxyl groups, its steric effect is enhanced, and the bonding and probability between the soluble salt alkali sodium ions and the bicarbonate, carbonate and chloride ions are further weakened, thereby achieving a high-efficiency soluble salt scale inhibition effect; the synergistic effect of the amphiphilic modified graphene oxide, surfactants and inorganic salts is used to further improve the high temperature resistance and scale inhibition performance of the salt scale inhibitor.

[0017] (2) The preparation process of the soluble alkaline scale inhibitor provided by the present invention is relatively simple, the reaction conditions are mild, it is phosphorus-free and green, it has good dispersibility, micro-nano scale (200-500nm), simple on-site preparation, and good compatibility with reservoirs. It is particularly suitable for high temperature, high alkali, and high mineralization soluble alkali salt water conditions, and can solve the problems of oil field water injection, fracturing backflow formations and wellbore salt deposition, and has good promotion prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the infrared spectrum of the amphiphilic modified graphene TAS-GO in the embodiment of the present invention.

[0019] Figure 2 This is a comparison chart of the static anti-salt scale effect of saturated solutions of three composite salts (NaHCO3:Na2CO3:NaCl=63:27:10, 45:45:10, 27:63:10) in Example 1 of the present invention without and with the addition of a scale inhibitor; Figure 3 This is a comparison chart of the salt deposition on the screen in the dynamic salt inhibition experiment of saturated solutions of three composite salts (NaHCO3:Na2CO3:NaCl=63:27:10, 45:45:10, 27:63:10) in Example 1 of the present invention without and with the addition of scale inhibitor. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0021] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0022] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and " / " or "including" are used in this specification, it indicates the presence of features, steps, operations and / or combinations thereof.

[0023] The experimental methods in the following examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples are commercially available unless otherwise specified. Among them, the sources of several main experimental raw materials are as follows: graphene oxide (AR, Evonik), 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AR, TCI Chemical), dodecylsilane coupling agent, hexadecylsilane coupling agent (industrial grade, Shandong Huachen), sodium dodecylbenzenesulfonate, sodium hexadecylsulfonate, sodium cocoylhydroxysulfonate (industrial grade, Shandong Chuangying Chemical).

[0024] Embodiment 1: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.5 g of graphene oxide (GO) was ultrasonically dispersed in 100 mL of deionized water for 1 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 70 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0025] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 0.5 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水=1:1) were mixed and reacted at 60℃ for 8h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0026] (3) Weigh 0.2 g of sodium dodecylbenzene sulfonate and 0.3 g of potassium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 30 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0027] like Figure 1 As shown in the infrared spectrum, 3276 cm -1 -OH stretching vibration peak, 2916 cm -1 、2853 cm -1 The peak at 1464 cm-1 is the stretching vibration peak of CH in -CH2-, indicating the introduction of a long carbon chain of alkyl. -1 The CN stretching vibration peak appeared at 1111 cm -1 , 1030 cm -1 It may be the stretching vibration peak of the naphthalene ring and sulfonic acid group or the stretching vibration peak of Si-OC; at 684cm -1 、719cm -1 、782cm -1 、905cm -1 It is the NH out-of-plane bending vibration peak.

[0028] Embodiment 2: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.6 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 1.5 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 80 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0029] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 0.5 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 60℃ for 8h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0030] (3) Weigh 0.2 g of sodium hexadecyl sulfate and 0.3 g of potassium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 30 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0031] Embodiment 3: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.75 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 2 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 80 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0032] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.0 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 70℃ for 7h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0033] (3) Weigh 0.3 g of sodium dodecylbenzene sulfonate and 0.4 g of sodium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 40 °C in a constant temperature water bath. Add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0034] Embodiment 4: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.8 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 2 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir, condense and reflux at 90 °C for 8 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0035] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.0 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 70℃ for 7h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0036] (3) Weigh 0.3 g of sodium hexadecyl sulfate and 0.4 g of sodium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 40 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0037] Embodiment 5: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.0 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and the mixture was stirred and condensed under reflux at 90 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0038] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.5 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 80℃ for 6h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0039] (3) Weigh 0.2 g of sodium dodecylbenzene sulfonate, 0.2 g of sodium coconut oil hydroxysulfonate, and 0.5 g of potassium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0040] Embodiment 6: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.2 g of graphene oxide (GO) was ultrasonically dispersed in 250 mL of deionized water for 2 h to form a GO dispersion; 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir and condense under reflux at 90 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0041] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 2.0 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 80℃ for 6h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0042] (3) Weigh 0.2 g of sodium hexadecyl sulfate, 0.2 g of sodium cocoyl hydroxysulfonate, and 0.5 g of sodium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse the mixture using an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0043] Comparative Example 1: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.5 g of graphene oxide (GO) was ultrasonically dispersed in 100 mL of deionized water for 1 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 70 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0044] (2) Weigh 0.2 g of sodium dodecylbenzene sulfonate and 0.3 g of potassium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 30°C in a constant temperature water bath. Then add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0045] Comparative Example 2: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.5 g of graphene oxide (GO) was ultrasonically dispersed in 100 mL of deionized water for 1 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 70 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0046] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 0.5 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 60℃ for 8h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0047] (3) Weigh 0.5 g of sodium dodecylbenzene sulfonate and dissolve it in 100 mL of deionized water. Heat the mixture to 30° C. in a constant temperature water bath. Add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0048] Comparative Example 3: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.5 g of graphene oxide (GO) was ultrasonically dispersed in 100 mL of deionized water for 1 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 70 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0049] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 0.5 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 60℃ for 8h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0050] (3) Weigh 0.5 g of potassium chloride and dissolve it in 100 mL of deionized water. Heat the mixture to 30 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it in an ultrasonic disperser for 30 min to prepare a soluble alkaline scale inhibitor.

[0051] Comparative Example 4: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.6 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 1.5 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 80 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0052] (2) Weigh 0.2 g of sodium hexadecyl sulfate and 0.3 g of potassium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 30 °C in a constant temperature water bath. Add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0053] Comparative Example 5: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.6 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 1.5 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 80 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0054] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 0.5 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 60℃ for 8h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0055] (3) Weigh 0.5 g of sodium hexadecyl sulfate and dissolve it in 100 mL of deionized water. Heat the mixture to 30 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0056] Comparative Example 6: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.6 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 1.5 h to form a GO dispersion; 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); the AS aqueous solution was continuously stirred and added to the GO dispersion at 10 mL / min, and continued to stir and condense at 80 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0057] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 0.5 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 60℃ for 8h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0058] (3) Weigh 0.5 g of potassium chloride and dissolve it in 100 mL of deionized water. Heat the mixture to 30 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it in an ultrasonic disperser for 30 min to prepare a soluble alkaline scale inhibitor.

[0059] Comparative Example 7: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.75 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 2 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and the mixture was stirred and condensed under reflux at 80 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0060] (2) Weigh 0.3 g of sodium dodecylbenzene sulfonate and 0.4 g of sodium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 40°C in a constant temperature water bath. Add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0061] Comparative Example 8: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.75 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 1 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and the mixture was stirred and condensed under reflux at 80 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0062] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.0 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 70℃ for 7h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0063] (3) Weigh 0.7 g of sodium dodecylbenzene sulfonate and dissolve it in 100 mL of deionized water. Heat the mixture to 40°C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0064] Comparative Example 9: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.75 g of graphene oxide (GO) was ultrasonically dispersed in 150 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 2 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and the mixture was stirred and condensed under reflux at 80 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0065] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.0 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 70℃ for 7h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower solid layer twice with deionized water, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0066] (3) Weigh 0.7 g of sodium chloride and dissolve it in 100 mL of deionized water. Heat the mixture to 40°C in a constant temperature water bath. Add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it in an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0067] Comparative Example 10: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.8 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 2 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir, condense and reflux at 90 °C for 8 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0068] (2) Weigh 0.3 g of sodium hexadecyl sulfate and 0.4 g of sodium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 40°C in a constant temperature water bath. Add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0069] Comparative Example 11: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.8 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 2 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir, condense and reflux at 90 °C for 8 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0070] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.0 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 70℃ for 7h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0071] (3) Weigh 0.7 g of sodium hexadecyl sulfate and dissolve it in 100 mL of deionized water. Heat the mixture to 40 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it in an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0072] Comparative Example 12: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 0.8 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 2 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 7.5); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir, condense and reflux at 90 °C for 8 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0073] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.0 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 70℃ for 7h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0074] (3) Weigh 0.7 g of sodium chloride and dissolve it in 100 mL of deionized water. Heat the mixture to 40°C in a constant temperature water bath. Add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it in an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0075] Comparative Example 13: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.0 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and the mixture was stirred and condensed under reflux at 90 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0076] (2) Weigh 0.2 g of sodium dodecylbenzene sulfonate, 0.2 g of sodium coconut oil hydroxysulfonate, and 0.5 g of potassium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Then add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0077] Comparative Example 14: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.0 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and the mixture was stirred and condensed under reflux at 90 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0078] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.5 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 80℃ for 6h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0079] (3) Weigh 0.45 g of sodium dodecylbenzene sulfonate and 0.45 g of sodium coconut oil hydroxysulfonate and dissolve them in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0080] Comparative Example 15: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.0 g of graphene oxide (GO) was ultrasonically dispersed in 200 mL of deionized water for 2 h to form a GO dispersion; 2.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and the mixture was stirred and condensed under reflux at 90 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0081] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 1.5 g dodecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 80℃ for 6h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0082] (3) Weigh 0.9 g of potassium chloride and dissolve it in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it in an ultrasonic disperser for 30 min to prepare a soluble alkaline scale inhibitor.

[0083] Comparative Example 16: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.2 g of graphene oxide (GO) was ultrasonically dispersed in 250 mL of deionized water for 2 h to form a GO dispersion; 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir and condense under reflux at 90 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0084] (2) Weigh 0.2 g of sodium hexadecyl sulfate, 0.2 g of sodium cocoyl hydroxysulfonate, and 0.5 g of sodium chloride and dissolve them in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Then add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder and disperse the mixture for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0085] Comparative Example 17: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.2 g of graphene oxide (GO) was ultrasonically dispersed in 250 mL of deionized water for 2 h to form a GO dispersion; 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir and condense under reflux at 90 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0086] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 2.0 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 80℃ for 6h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0087] (3) Weigh 0.45 g of sodium hexadecyl sulfate and 0.45 g of sodium coconut hydroxysulfonate and dissolve them in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it for 30 min using an ultrasonic disperser to obtain a soluble alkaline scale inhibitor.

[0088] Comparative Example 18: (1) Synthesis of hydrophilic modified graphene oxide AS-GO: 1.2 g of graphene oxide (GO) was ultrasonically dispersed in 250 mL of deionized water for 2 h to form a GO dispersion; 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) was added to 10 mL of deionized water and neutralized with 3 mol / L sodium hydroxide solution to a weak alkaline state to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred and added to the GO dispersion at a rate of 10 mL / min, and continued to stir and condense under reflux at 90 °C for 12 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0089] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g AS-GO intermediate, 2.0 g hexadecylsilane coupling agent, 100 g ethanol / water mixture (m 乙醇 :m 水 =1:1) were mixed and reacted at 80℃ for 6h; then centrifuged at 4500r / min for 30min, and the supernatant was discarded; ethanol / water mixed solution (m 乙醇 :m 水 =1:1), washing the lower layer of solid with deionized water for 3 times, and then drying at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0090] (3) Weigh 0.9 g of sodium chloride and dissolve it in 100 mL of deionized water. Heat the mixture to 50 °C in a constant temperature water bath. Add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder and disperse it in an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0091] Performance comparison: The soluble alkaline scale inhibitors in Examples 1 to 6 and Comparative Examples 1 to 18 and commercially available products (sodium polyepoxysuccinate, sodium polyaspartate, sodium polycarboxylate) were subjected to a comparative experiment on scale inhibition effects, including stability (30°C, standing), static salt inhibition rate and dynamic salt inhibition rate tests. The specific test methods are as follows: (1) Static salt inhibition rate test method a) Take 100 mL of tap water in a wide-mouth bottle, add excess composite salt until the solution is supersaturated, place in a 95°C water bath and stir to dissolve for 30 minutes, and filter out the undissolved salt particles in the solution while it is hot; b) Take out the salt solution in a) and place it at 10℃ to cool for 24h, transfer the solution to a suction filtration funnel, filter it for about 5min, place the filter paper in a vacuum drying oven (0.09MPa, 45℃) to dry, weigh and calculate the mass of the precipitated salt scale as w0; c) adding a scale inhibitor to the salt solution in a), dissolving it for 30 min, letting it stand for 8 h and then filtering it while hot, and repeating the remaining steps a) and b) to obtain a scale mass of w1.

[0092] The calculation formula for static scale inhibition rate is as follows: Y sj = (w 0 -w 1 ) / w 0 ×100% ; in, Y sjis the static scale inhibition rate, %; w 0 is the mass of salt without adding scale inhibitor, g; w 1 The mass of salt added as scale inhibitor, g.

[0093] (2) Dynamic salt inhibition rate test method Prepare a saturated solution of the target composite salt, heat it at 95°C, stir it at 200r / min, and after it is completely dissolved, set different pump speeds to allow the brine to circulate continuously in the casing (tube diameter 10mm, tube length 1m), and cool the casing with 10°C tap water circulation. Observe the salt formation on the sieve (100 mesh), take photos and record them at regular intervals. Before each experiment, weigh the inserted sieve and record the mass M0 of the sieve. After the experiment, take out the sieve, put it in the dryer to dry, weigh it, and record the mass M1 of the sieve with attached salt crystals; take out the salt scale attached to the tube wall, filter it, dry it, weigh it, and record the mass M2. The amount of salt is calculated according to the following formula: ; Among them, Y sd is the dynamic scale inhibition rate, %; M 0 is the mass of the sieve before the experiment, g; M 1 is the mass of the sieve after the experiment without adding inhibitor, g; M 2 is the mass of salt scale on the pipe wall after the test without adding inhibitor, g; M 1 ’ is the mass of the sieve after the inhibitor experiment, g; M 2 ’ The mass of salt scale on the pipe wall after the inhibitor test, g.

[0094] According to the above method, three saturated solutions of composite salt NaHCO3:Na2CO3:NaCl with different ratios of 63:27:10, 45:45:10 and 27:63:10 were prepared, and the static and dynamic salt inhibition effects of different scale inhibitors were compared. The test results are shown in Tables 1 and 2.

[0095] Table 1 Comparison of scale inhibitor stability and static scale inhibition rate .

[0096] Table 2 Comparison of dynamic scale inhibition rate .

[0097] like Figure 2 and Figure 3 As shown, it can be seen from the test results of static and dynamic scale inhibition rates in Table 1 and Table 2 that, at the same concentration, compared with the same dosage of the control example without amphiphilic modified graphene oxide nanofluid inhibitor and conventional inhibitors (sodium polyepoxysuccinate, polyaspartic acid, sodium polycarboxylate), the inhibition rate of the graphene oxide nanofluid inhibitor without amphiphilic modification is only between 40% and 70%, and the conventional inhibitors are all lower than 40%. Without any of the components of amphiphilic modified graphene oxide, surfactant, and inorganic salt, the scale inhibition rate and stability are greatly reduced, while the soluble scale inhibitor in the embodiment of the present invention has excellent salt inhibition effect, and the static and dynamic scale inhibition rates of 50 mg / L reach 92% and 95% respectively, indicating that the various substances in the components have obvious synergistic scale inhibition and synergistic effects, and the addition of inorganic salts can improve the product stability to more than 90 days. It shows that the amphiphilic modified graphene nanofluid scale inhibitor of the present invention has a good effect on the inhibition of soluble sodium bicarbonate type alkali salt crystals.

[0098] In summary, the present invention discloses a soluble alkaline scale inhibitor and a preparation method thereof, which belong to the technical field of oilfield chemistry; the soluble alkaline scale inhibitor is prepared from amphiphilic modified graphene oxide TAS-GO, a surfactant, an inorganic salt and deionized water; the amphiphilic modified graphene oxide TAS-GO contains a large number of carboxyl groups, sulfonic acid groups and hydroxyl groups, etc., and has good metal ion chelating properties; at the same time, through the hydrophobic association and hydrogen bonding between the modified graphene grafted long carbon chains, the bonding probability between the soluble salt and alkali sodium ions and the bicarbonate, carbonate and chloride ions is further weakened, and through the synergistic effect of the amphiphilic modified graphene oxide TAS-GO, the surfactant and the inorganic salt, the scale inhibition effect is further increased, and the invention is particularly suitable for high temperature, high alkali and high mineralization soluble alkali salt water quality conditions, and can solve the problems of oilfield water injection, fracturing backflow formation and wellbore salt deposition, and has a good effect, and has a good promotion prospect.

[0099] At this point, those skilled in the art recognize that, although the embodiments of the present invention have been shown and described in detail herein, many other variations or modifications that conform to the principles of the present invention can still be directly determined or derived based on the contents disclosed in the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and recognized as covering all such other variations or modifications.

Claims

1. A soluble alkaline scale inhibitor, characterized in that: The soluble alkaline scale inhibitor includes: Amphiphilic modified graphene oxide TAS-GO, surfactant, inorganic salt and water; The mass concentration of the amphiphilic modified graphene oxide TAS-GO in the inhibitor is 0.1-0.5%; The mass concentration of the surfactant in the inhibitor is 0.2 to 0.4%; The mass concentration of the inorganic salt in the inhibitor is 0.3 to 0.5%; The inorganic salt is one or more of potassium chloride and sodium chloride; The surfactant is one or more of sodium dodecylbenzene sulfonate, sodium hexadecyl sulfate, sodium hexadecyl sulfonate, sodium lauryl polyoxyethylene ether sulfate, sodium di(laureth-7) citrate, and sodium coconut oil hydroxysulfonate.

2. A soluble alkaline scale inhibitor as claimed in claim 1, characterized in that: The structural formula of the amphiphilic modified graphene oxide TAS-GO is: 。 3. A soluble alkaline scale inhibitor as claimed in claim 1, characterized in that: The water is deionized water; the surfactant is one or more of sodium dodecylbenzene sulfonate, sodium hexadecyl sulfonate, and sodium coconut oil hydroxy sulfonate.

4. A soluble alkaline scale inhibitor as claimed in claim 1, characterized in that: The specific preparation method of the amphiphilic modified graphene oxide TAS-GO is: Step S1: Preparation of hydrophilic modified graphene oxide AS-GO intermediate: 0.5-1.2g of graphene oxide GO was ultrasonically dispersed in 100-250mL of deionized water for 1-2h to form a GO dispersion; 6-amino-4-hydroxy-2-naphthalenesulfonic acid AS was neutralized with 1-3mol / L sodium hydroxide solution to form an AS aqueous solution; the AS aqueous solution was continuously stirred, and the AS aqueous solution was added to the GO dispersion at a rate of 5-10mL / min, and the stirring reflux reaction was continued at 70-90°C for 8-12h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the supernatant was dried to obtain a hydrophilic modified graphene oxide AS-GO intermediate; the reaction formula for the preparation of the hydrophilic modified graphene oxide AS-GO intermediate is as follows: ； Step S2: Preparation of amphiphilic modified graphene oxide TAS-GO: The hydrophilic modified graphene oxide AS-GO intermediate obtained in step S1, the silane coupling agent, and the ethanol / water mixture are mixed and reacted at 60-80°C for 5-8 hours; then centrifuged at 4500r / min for 30 minutes, and the upper clear liquid is discarded; after washing the lower solid 2-3 times, it is dried at 80°C to obtain the amphiphilic modified graphene oxide TAS-GO; the reaction formula for preparing the amphiphilic modified graphene oxide TAS-GO is as follows: 。 5. A soluble alkaline scale inhibitor as claimed in claim 4, characterized in that: During the reaction process of step S1, the mass ratio of graphene oxide GO to 6-amino-4-hydroxy-2-naphthalenesulfonic acid is 1:2 to 1:

3.

6. A soluble alkaline scale inhibitor as claimed in claim 4, characterized in that: The pH value of the AS aqueous solution in step S1 is 7-9; the drying conditions of the supernatant are: 50° C. and a vacuum degree of -0.088 MPa.

7. A soluble alkaline scale inhibitor as claimed in claim 4, characterized in that: The pH value of the AS aqueous solution in step S1 is 7-8; the ethanol / water mixed solution in step S2 is ethanol and water in a mass ratio of 1:1; the lower layer solid is washed with the ethanol / water mixed solution and deionized water respectively.

8. A soluble alkaline scale inhibitor as claimed in claim 4, characterized in that: The mass ratio of the hydrophilic modified graphene oxide AS-GO intermediate to the silane coupling agent in step S2 is 1:1-1:4; the silane coupling agent is one of dodecane silane coupling agent and hexadecane silane coupling agent.

9. A method for preparing a soluble alkaline scale inhibitor according to claim 1, characterized in that: The preparation method is specifically: The amphiphilic modified graphene oxide TAS-GO is mixed with an inorganic salt, a surfactant and water according to the mass concentration ratio, and then heated at 30 to 50° C. and ultrasonically dispersed for 10 to 30 minutes to obtain the soluble alkaline scale inhibitor.

Images