A soluble alkaline salt scale inhibitor and its preparation method

Abstract

The present invention discloses a soluble alkaline scale inhibitor and its preparation method, belonging to the technical field of oilfield chemistry; the soluble alkaline scale inhibitor is prepared from amphiphilic modified graphene oxide, surfactant, inorganic salt and deionized water; the amphiphilic modified graphene oxide 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 bond action between the grafted long carbon chains of the modified graphene, the bonding probability between the sodium ions of the soluble saline and bicarbonate, carbonate and chloride ions is further weakened, and through the synergistic action of the amphiphilic modified graphene oxide, surfactant and inorganic salt, the scale inhibition effect is further increased, especially suitable for the water quality conditions of soluble alkali salts with high temperature, high alkalinity and high salinity, and can solve the problems of salt formation in oilfield water injection, fracturing fluid backflow formation and wellbore, and has good promotion prospects.

Description

Technical Field

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

[0002] In high-salinity wells, due to the high salinity of formation water, 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, a high water injection pressure, a short effective period, and huge economic losses. Preventing salt scale by using a salt inhibitor is a method of injecting a chemical agent into the well to inhibit salt formation. This method has received extensive attention due to its simple operation, low cost, high efficiency, and no impact on the quality and production of crude oil. Salt scale inhibitors for soluble salts (mainly sodium chloride) and insoluble salt scales (calcium carbonate, barium sulfate, etc.) have been developed. For example, phosphate salts, carboxylic acid polyhomopolymers, and environmentally friendly polyaspartic acid PASP and polyepoxysuccinic acid PESA can all achieve good scale inhibition effects. However, for the problem of salt formation in high-salinity formation water dominated by sodium carbonate and sodium bicarbonate at high temperatures in the formation or wellbore, due to the different chemical properties (solubility, pH, ionic bonding strength, crystal morphology) of such composite salts from conventional salt scales, the anti-salt effect of conventional low-molecular-weight multi-anion scale inhibitors or salt inhibitors is limited.

[0003] Through retrieval, the following several patent literature related to the present invention patent application are found. A preparation method of 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 inhibitors mainly target the problem of salt formation prevention in saturated or supersaturated salt solutions mainly composed of sodium chloride, but have limited salt crystallization inhibition effects on main salts such as sodium bicarbonate or sodium carbonate. The application of disodium EDTA as an inhibitor for low-temperature crystallization precipitation of sodium carbonate solution CN103497749B reports the preparation and application of an ELYZ-09 sodium carbonate crystallization inhibitor synthesized from ethylenediamine, hydroxyacetonitrile, and isopropanol, which mainly solves the problem of crystallization precipitation of sodium carbonate solution during transportation. It has a good anti-crystallization effect on sodium carbonate solution when the temperature drops from 30°C to 10°C at a relatively low temperature, but the effect on high-temperature oil reservoirs and saturated solutions of composite salts of sodium carbonate / sodium bicarbonate / sodium chloride is not yet clear. Summary of the Invention

[0004] The object of the present invention is to overcome the shortcomings of the prior art and provide a soluble alkaline scale inhibitor applicable thereto and a preparation method thereof, belonging to the technical field of oilfield chemistry, which can effectively prevent the formation of soluble sodium carbonate, sodium bicarbonate and their composite salts, and still has good scale inhibition effect under high temperature, high salt and alkaline conditions; the soluble alkaline scale inhibitor is prepared from amphiphilic modified graphene oxide TAS-GO, surfactant, 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 bond actions between the grafted long carbon chains of the modified graphene, the bonding probability between the sodium ions of the soluble alkaline salt and bicarbonate, carbonate and chloride ions is further weakened, and through the synergistic action of the amphiphilic modified graphene oxide TAS-GO, surfactant and inorganic salt, the scale inhibition effect is further increased, especially applicable to the water quality conditions of soluble alkaline salts with high temperature, high alkalinity and high salinity, and can solve the problems of salt formation in oilfield water injection, fracturing flowback formation and wellbore, and has good effect and good popularization prospect.

[0005] To achieve the above technical effects, the following technical solutions are adopted:

[0006] A soluble alkaline scale inhibitor applicable thereto, comprising:

[0007] Amphiphilic modified graphene oxide TAS-GO, surfactant, inorganic salt and water;

[0008] The mass concentration of the amphiphilic modified graphene oxide TAS-GO in the inhibitor is 0.1-0.5%;

[0009] The mass concentration of the surfactant in the inhibitor is 0.2-0.4%;

[0010] The mass concentration of the inorganic salt in the inhibitor is 0.3-0.5%;

[0011] The inorganic salt is one or more of potassium chloride and sodium chloride;

[0012] The surfactant is one or more of sodium dodecylbenzenesulfonate, sodium hexadecyl sulfate, sodium hexadecyl sulfonate, sodium lauryl polyoxyethylene ether sulfate, sodium bis(lauryl polyether-7) citrate, and sodium cocoyl hydroxysulfonate.

[0013] Further, the structural formula of the amphiphilic modified graphene oxide TAS-GO is:

[0014] 。

[0015] Further, the water is deionized water; the surfactant is one or more of sodium dodecylbenzenesulfonate, sodium hexadecylsulfonate, and sodium cocoyl hydroxysulfonate.

[0016] Further, the specific preparation method of the amphiphilic modified graphene oxide TAS-GO is as follows:

[0017] Step S1: Preparation of the hydrophilic modified graphene oxide AS-GO intermediate:

[0018] Take 0.5 - 1.2 g of graphene oxide GO and ultrasonically disperse it in 100 - 250 mL of deionized water for 1 - 2 h to form a GO dispersion; neutralize 6-amino-4-hydroxy-2-naphthalenesulfonic acid AS with 1 - 3 mol / L sodium hydroxide solution to form an AS aqueous solution; continuously stir the AS aqueous solution, and at the same time add the AS aqueous solution to the GO dispersion at a rate of 5 - 10 mL / min, and continue to stir and reflux at 70 - 90 °C for 8 - 12 h; centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it to obtain the hydrophilic modified graphene oxide AS-GO intermediate; the reaction formula of the reaction process is as follows:

[0019] 。

[0020] Step S2: Preparation of the amphiphilic modified graphene oxide TAS-GO:

[0021] Mix the hydrophilic modified graphene oxide AS-GO intermediate, silane coupling agent, and ethanol / water mixture obtained in Step S1, and react at 60 - 80 °C for 5 - 8 h; then centrifuge at 4500 r / min for 30 min, and discard the supernatant; wash the lower layer solid 2 - 3 times and then dry it at 80 °C to obtain the amphiphilic modified graphene oxide TAS-GO; the reaction formula of the reaction process is as follows:

[0022] 。

[0023] Further, in the reaction process of Step S1, the mass ratio of graphene oxide GO to 6-amino-4-hydroxy-2-naphthalenesulfonic acid is 1:2 - 1:3.

[0024] Further, the pH value of the AS aqueous solution in Step S1 is 7 - 9; the drying conditions of the supernatant are: 50 °C, and the vacuum degree is -0.088 MPa.

[0025] Further, the pH value of the AS aqueous solution in Step S1 is 7 - 8; the ethanol / water mixture in Step S2 is an ethanol and water mixture with a mass ratio of 1:1; the lower layer solid is washed with the ethanol / water mixture and deionized water respectively.

[0026] Further, the mass ratio of the hydrophilic modified graphene oxide AS-GO intermediate in step S2 to the silane coupling agent is 1:1 to 1:4; the silane coupling agent is one of dodecane silane coupling agent and hexadecane silane coupling agent.

[0027] Further, the preparation method is specifically as follows:

[0028] The amphiphilic modified graphene oxide TAS-GO, inorganic salt, surfactant and water are mixed according to the mass concentration ratio, and then heated and ultrasonically dispersed at 30-50 °C for 10-30 min to obtain the soluble alkaline salt scale inhibitor.

[0029] Further, the soluble alkaline salt scale inhibitor is applied to the fields of oilfield water injection and fracturing flowback scale inhibition.

[0030] Beneficial effects:

[0031] (1) The present invention provides a soluble alkali salt scale inhibitor. The key component of this scale inhibitor 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 can shield the anions and cations of soluble salts through electrostatic interaction, and has good metal ion chelating property; at the same time, it also contains large-scale conjugated rings and hydrophobic long carbon chains. Through the hydrophobic association between the long carbon chains grafted on the single-layer modified graphene and the hydrogen bond interaction between carboxyl groups and hydroxyl groups, the steric hindrance effect is enhanced, further weakening the bonding effect and probability between sodium ions and bicarbonate ions, carbonate ions and chloride ions in soluble alkaline salts, so as to achieve an efficient soluble salt scale inhibition effect; the synergistic effect of amphiphilic modified graphene oxide, surfactant and inorganic salt is used to further improve the high temperature resistance and scale inhibition performance of the salt scale inhibitor.

[0032] (2) The preparation process of the soluble alkaline salt scale inhibitor provided by the present invention is relatively simple, the reaction conditions are mild, it is phosphorus-free, green and environmentally friendly, has good dispersibility, is in the micro-nano scale (200-500 nm), is simple to prepare on site, and has good compatibility with the reservoir. It is especially suitable for the water quality conditions of soluble alkaline salts with high temperature, high alkalinity and high salinity, and has a good effect on solving the problems of salt formation in oilfield water injection, fracturing flowback formation and wellbore, and has good promotion prospects. Description of the drawings

[0033] Figure 1 It is the infrared spectrum of the amphiphilic modified graphene TAS-GO in the embodiment of the present invention.

[0034] Figure 2 It is for three kinds of composite salts (NaHCO 3 :Na 2 CO3 : NaCl = 63:27:10, 45:45:10, 27:63:10) Comparison diagrams of the static salt scale inhibition effects of saturated solutions with and without the addition of a salt scale inhibitor;

[0035] Figure 3 For the three composite salts (NaHCO 3 : Na 2 CO 3 : NaCl = 63:27:10, 45:45:10, 27:63:10) Comparison diagrams of the salt deposition on the sieve in the dynamic salt scale inhibition experiments of saturated solutions with and without the addition of a salt scale inhibitor. Detailed implementation manners

[0036] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with 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.

[0037] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanations of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0038] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless otherwise clearly specified in the context, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "include" and " / " or "including" are used in this specification, they indicate the presence of features, steps, operations and / or their combinations.

[0039] The experimental methods in the following embodiments are all conventional methods unless otherwise specified. The materials, reagents, etc. used in the following embodiments can all be obtained through commercial channels unless otherwise specified. Among them, the sources of several main experimental raw materials are as follows: graphene oxide (AR, Constellation Winstone), 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AR, TCI Chemicals), dodecyl silane coupling agent, hexadecyl silane coupling agent (industrial grade, Shandong Huachen), sodium dodecylbenzenesulfonate, sodium hexadecylsulfonate, sodium coconut oil hydroxy sulfonate (industrial grade, Shandong Chuangying Chemical Industry).

[0040] Example 1:

[0041] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.5 g of graphene oxide (GO) and ultrasonically disperse it in 100 mL of deionized water for 1 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 70 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0042] (2)Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 0.5 g of dodecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), and react at 60 °C for 8 h; Then centrifuge at 4500 r / min for 30 min and discard the supernatant; Wash the lower solid twice with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water, and then dry at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0043] (3)Weigh 0.2 g of sodium dodecylbenzenesulfonate and 0.3 g of potassium chloride, dissolve them in 100 mL of deionized water, add them to 30 °C with a constant temperature water bath, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0044] As Figure 1 shown, in the infrared spectrum, the peak at 3276 cm -1 is the stretching vibration peak of -OH, and the peaks at 2916 cm -1 , 2853 cm -1 are the C-H stretching vibration peaks in -CH 2 -, indicating the introduction of an alkyl long carbon chain; The C-N stretching vibration peak appears at 1464 cm -1 , and at the same time, the peaks at 1111 cm -1 , 1030 cm -1 may be the stretching vibration peaks of the naphthalene ring and sulfonic acid group or the Si-O-C stretching vibration peak; The N-H out-of-plane bending vibration peaks are at 684 cm -1 , 719 cm -1 , 782 cm -1 , 905 cm -1 .

[0045] Example 2:

[0046] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.6 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 1.5 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and condense and reflux at 80 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0047] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 0.5 g of cetyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 :m 水 = 1:1), react at 60 °C for 8 h; Then centrifuge at 4500 r / min for 30 min, and discard the supernatant; Wash the lower layer solid twice with ethanol / water mixture (m 乙醇 :m 水 = 1:1) and deionized water, and then dry at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0048] (3) Weigh 0.2 g of sodium hexadecylsulfonate and 0.3 g of potassium chloride, dissolve them in 100 mL of deionized water, add them to 30 °C with a constant temperature water bath, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0049] Example 3:

[0050] (1)Synthesis of hydrophilically modified graphene oxide AS-GO: Take 0.75 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 2 h to form a GO dispersion; Add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 2 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and condense and reflux at 80 °C for 10 h; Centrifuge the reacted mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilically modified graphene oxide (AS-GO).

[0051] (2)Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 1.0 g of dodecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), and react at 70 °C for 7 h; Then centrifuge at 4500 r / min for 30 min, and discard the supernatant; Wash the lower layer solid with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water twice, and then dry at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0052] (3)Weigh 0.3 g of sodium dodecylbenzenesulfonate and 0.4 g of sodium chloride, dissolve them in 100 mL of deionized water, add them to 40 °C with a constant temperature water bath, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0053] Example 4:

[0054] (1)Synthesis of hydrophilically modified graphene oxide AS-GO: Take 0.8 g of graphene oxide (GO) and ultrasonically disperse it in 200 mL of deionized water for 2 h to form a GO dispersion; Add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 2 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and condense and reflux at 90 °C for 8 h; Centrifuge the reacted mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilically modified graphene oxide (AS-GO).

[0055] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g of AS-GO intermediate, 1.0 g of cetyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1) were mixed and reacted at 70 °C for 7 h; then centrifuged at 4500 r / min for 30 min, and the supernatant was discarded; the lower layer solid was washed 3 times with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water, and then dried at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0056] (3) Weigh 0.3 g of sodium hexadecylsulfonate and 0.4 g of sodium chloride, dissolve them in 100 mL of deionized water, add them to 40 °C with a constant temperature water bath, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0057] Example 5:

[0058] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 1.0 g of graphene oxide (GO) and ultrasonically disperse it 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 to weak alkalinity with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); the AS aqueous solution was continuously stirred, and at the same time added to the GO dispersion at a rate of 10 mL / min, and continued to stir and reflux under condensation at 90 °C for 10 h; the reaction mixture was centrifuged at 4500 r / min for 30 min, and the upper layer clear liquid was taken and dried (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0059] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: 0.5 g of AS-GO intermediate, 1.5 g of dodecyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1) were mixed and reacted at 80 °C for 6 h; then centrifuged at 4500 r / min for 30 min, and the supernatant was discarded; the lower layer solid was washed 3 times with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water, and then dried at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0060] (3) Weigh 0.2 g of sodium dodecylbenzenesulfonate, 0.2 g of sodium cocoyl hydroxysulfonate, and 0.5 g of potassium chloride, dissolve them in 100 mL of deionized water, heat it to 50 °C using 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.

[0061] Example 6:

[0062] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 1.2 g of graphene oxide (GO) and ultrasonically disperse it in 250 mL of deionized water for 2 h to form a GO dispersion; Add 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0063] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 2.0 g of hexadecyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 :m 水 = 1:1), react at 80 °C for 6 h; Then centrifuge at 4500 r / min for 30 min and discard the supernatant; Wash the lower layer solid 3 times with ethanol / water mixture (m 乙醇 :m 水 = 1:1) and deionized water respectively, and then dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0064] (3) Weigh 0.2 g of sodium hexadecylsulfonate, 0.2 g of sodium cocoyl hydroxysulfonate, and 0.5 g of sodium chloride, dissolve them in 100 mL of deionized water, heat it to 50 °C using 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.

[0065] Comparative Example 1:

[0066] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.5 g of graphene oxide (GO) and ultrasonically disperse it in 100 mL of deionized water for 1 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 70 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0067] (2)Weigh 0.2 g of sodium dodecylbenzenesulfonate and 0.3 g of potassium chloride, dissolve them in 100 mL of deionized water, heat it to 30 °C with a constant temperature water bath, then add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0068] Comparative Example 2:

[0069] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.5 g of graphene oxide (GO) and ultrasonically disperse it in 100 mL of deionized water for 1 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 70 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (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: Mix 0.5 g of AS-GO intermediate, 0.5 g of dodecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 :m 水 = 1:1), react at 60 °C for 8 h; Then centrifuge at 4500 r / min for 30 min, discard the supernatant; Wash the lower layer solid twice with ethanol / water mixture (m 乙醇 :m 水 = 1:1) and deionized water respectively, and dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0071] (3) Weigh 0.5 g of sodium dodecylbenzenesulfonate and dissolve it in 100 mL of deionized water. Use a constant temperature water bath to heat it to 30 °C, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and use an ultrasonic disperser to disperse it for 30 min to obtain a soluble alkaline scale inhibitor.

[0072] Comparative Example 3:

[0073] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.5 g of graphene oxide (GO) and ultrasonically disperse it in 100 mL of deionized water for 1 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and condense and reflux at 70 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0074] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 0.5 g of dodecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 60 °C for 8 h; Then centrifuge at 4500 r / min for 30 min and discard the supernatant; Wash the lower layer solid with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water twice, and then dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0075] (3) Weigh 0.5 g of potassium chloride and dissolve it in 100 mL of deionized water. Use a constant temperature water bath to heat it to 30 °C, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and use an ultrasonic disperser to disperse it for 30 min to obtain a soluble alkaline scale inhibitor.

[0076] Comparative Example 4:

[0077] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.6 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 1.5 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 80 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0078] (2)Weigh 0.2 g of sodium hexadecylsulfonate and 0.3 g of potassium chloride, dissolve them in 100 mL of deionized water, add them to 30 °C with a constant temperature water bath, then add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0079] Comparative Example 5:

[0080] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.6 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 1.5 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 80 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (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: Mix 0.5 g of AS-GO intermediate, 0.5 g of cetylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 60 °C for 8 h; Then centrifuge at 4500 r / min for 30 min, discard the supernatant; Wash the lower layer solid with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water twice respectively, and dry at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0082] (3) Weigh 0.5 g of sodium hexadecyl sulfonate and dissolve it in 100 mL of deionized water. Add it to 30 °C using 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.

[0083] Comparative Example 6:

[0084] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.6 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 1.5 h to form a GO dispersion; Add 1.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to neutral with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 80 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0085] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 0.5 g of hexadecyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 60 °C for 8 h; Then centrifuge at 4500 r / min for 30 min, and discard the supernatant; Wash the lower layer solid twice with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water respectively, and dry at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0086] (3) Weigh 0.5 g of potassium chloride and dissolve it in 100 mL of deionized water. Add it to 30 °C using 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.

[0087] Comparative Example 7:

[0088] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.75 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 2 h to form a GO dispersion; Add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 2 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 80 °C for 10 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0089] (2)Weigh 0.3 g of sodium dodecylbenzenesulfonate and 0.4 g of sodium chloride, dissolve them in 100 mL of deionized water, heat it to 40 °C with a constant temperature water bath, then add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to prepare a soluble alkaline scale inhibitor.

[0090] Comparative Example 8:

[0091] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.75 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 2 h to form a GO dispersion; Add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 1 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 80 °C for 10 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0092] (2)Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 1.0 g of dodecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 70 °C for 7 h; Then centrifuge at 4500 r / min for 30 min, discard the supernatant; Wash the lower layer solid with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water twice respectively, and then dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0093] (3) Weigh 0.7 g of sodium dodecylbenzenesulfonate and dissolve it in 100 mL of deionized water. Add it to 40 °C using 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.

[0094] Comparative Example 9:

[0095] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.75 g of graphene oxide (GO) and ultrasonically disperse it in 150 mL of deionized water for 2 h to form a GO dispersion; Add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 2 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 80 °C for 10 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0096] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 1.0 g of dodecyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), and react at 70 °C for 7 h; Then centrifuge at 4500 r / min for 30 min, and discard the supernatant; Wash the lower layer solid twice with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water respectively, and dry at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0097] (3) Weigh 0.7 g of sodium chloride and dissolve it in 100 mL of deionized water. Add it to 40 °C using 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.

[0098] Comparative Example 10:

[0099] (1)Synthesis of hydrophilically modified graphene oxide AS-GO: Take 0.8 g of graphene oxide (GO) and ultrasonically disperse it in 200 mL of deionized water for 2 h to form a GO dispersion; add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weakly alkaline with 2 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 8 h; centrifuge the reacted mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilically modified graphene oxide (AS-GO).

[0100] (2)Weigh 0.3 g of sodium hexadecylsulfonate and 0.4 g of sodium chloride, dissolve them in 100 mL of deionized water, heat it to 40 °C with a constant temperature water bath, then add 0.3 g of hydrophilically modified graphene oxide (AS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0101] Comparative Example 11:

[0102] (1)Synthesis of hydrophilically modified graphene oxide AS-GO: Take 0.8 g of graphene oxide (GO) and ultrasonically disperse it in 200 mL of deionized water for 2 h to form a GO dispersion; add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weakly alkaline with 2 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 8 h; centrifuge the reacted mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilically modified graphene oxide (AS-GO).

[0103] (2)Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 1.0 g of hexadecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 :m 水 = 1:1), react at 70 °C for 7 h; then centrifuge at 4500 r / min for 30 min, discard the supernatant; wash the lower layer solid with ethanol / water mixture (m 乙醇 :m 水 = 1:1) and deionized water three times, and then dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0104] (3) Weigh 0.7 g of sodium hexadecyl sulfonate and dissolve it in 100 mL of deionized water. Add it to 40 °C using 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.

[0105] Comparative Example 12:

[0106] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 0.8 g of graphene oxide (GO) and ultrasonically disperse it in 200 mL of deionized water for 2 h to form a GO dispersion; Add 2.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 2 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 7.5); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 8 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0107] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 1.0 g of hexadecyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), and react at 70 °C for 7 h; Then centrifuge at 4500 r / min for 30 min, and discard the supernatant; Wash the lower layer solid 3 times with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water respectively, and dry at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0108] (3) Weigh 0.7 g of sodium chloride and dissolve it in 100 mL of deionized water. Add it to 40 °C using 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.

[0109] Comparative Example 13:

[0110] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 1.0 g of graphene oxide (GO) and ultrasonically disperse it in 200 mL of deionized water for 2 h to form a GO dispersion; Add 2.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 10 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0111] (2)Weigh 0.2 g of sodium dodecylbenzenesulfonate, 0.2 g of sodium cocoyl hydroxysulfonate, and 0.5 g of potassium chloride, dissolve them in 100 mL of deionized water, heat it to 50 °C with a constant temperature water bath, then add 0.3 g of hydrophilic modified graphene oxide (AS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0112] Comparative Example 14:

[0113] (1)Synthesis of hydrophilic modified graphene oxide AS-GO: Take 1.0 g of graphene oxide (GO) and ultrasonically disperse it in 200 mL of deionized water for 2 h to form a GO dispersion; Add 2.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 10 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0114] (2)Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 1.5 g of dodecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 80 °C for 6 h; Then centrifuge at 4500 r / min for 30 min, discard the supernatant; Wash the lower layer solid 3 times with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water respectively, and then dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0115] (3) Weigh 0.45 g of sodium dodecylbenzenesulfonate and 0.45 g of sodium cocoyl hydroxysulfonate, dissolve them in 100 mL of deionized water, heat it to 50 °C using 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.

[0116] Comparative Example 15:

[0117] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 1.0 g of graphene oxide (GO) and ultrasonically disperse it in 200 mL of deionized water for 2 h to form a GO dispersion; Add 2.5 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weak alkalinity with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 10 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0118] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 1.5 g of dodecyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 80 °C for 6 h; Then centrifuge at 4500 r / min for 30 min and discard the supernatant; Wash the lower layer solid 3 times with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water respectively, and dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0119] (3) Weigh 0.9 g of potassium chloride and dissolve it in 100 mL of deionized water, heat it to 50 °C using 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.

[0120] Comparative Example 16:

[0121] (1)Synthesis of hydrophilically modified graphene oxide AS-GO: Take 1.2 g of graphene oxide (GO) and ultrasonically disperse it in 250 mL of deionized water for 2 h to form a GO dispersion; Add 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weakly alkaline with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 12 h; Centrifuge the reacted mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilically modified graphene oxide (AS-GO).

[0122] (2)Weigh 0.2 g of sodium hexadecylsulfonate, 0.2 g of sodium cocoamphohydroxypropylsulfonate, and 0.5 g of sodium chloride, dissolve them in 100 mL of deionized water, heat it to 50 °C with a constant temperature water bath, then add 0.3 g of hydrophilically modified graphene oxide (AS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to prepare a soluble alkaline scale inhibitor.

[0123] Comparative Example 17:

[0124] (1)Synthesis of hydrophilically modified graphene oxide AS-GO: Take 1.2 g of graphene oxide (GO) and ultrasonically disperse it in 250 mL of deionized water for 2 h to form a GO dispersion; Add 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, and neutralize it to weakly alkaline with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); Continuously stir the AS aqueous solution, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 12 h; Centrifuge the reacted mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilically modified graphene oxide (AS-GO).

[0125] (2)Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 2.0 g of hexadecylsilane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 80 °C for 6 h; Then centrifuge at 4500 r / min for 30 min, discard the supernatant; Wash the lower layer solid 3 times with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water respectively, and dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0126] (3) Weigh 0.45 g of sodium hexadecyl sulfonate and 0.45 g of sodium cocoyl hydroxysulfonate, dissolve them in 100 mL of deionized water, heat it to 50 °C using a constant temperature water bath, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0127] Comparative Example 18:

[0128] (1) Synthesis of hydrophilic modified graphene oxide AS-GO: Take 1.2 g of graphene oxide (GO) and ultrasonically disperse it in 250 mL of deionized water for 2 h to form a GO dispersion; Add 3.0 g of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (AS) to 10 mL of deionized water, neutralize it to weak alkalinity with 3 mol / L sodium hydroxide solution to form an AS aqueous solution (pH = 8); Stir the AS aqueous solution continuously, and at the same time add it to the GO dispersion at a rate of 10 mL / min, and continue to stir and reflux under condensation at 90 °C for 12 h; Centrifuge the reaction mixture at 4500 r / min for 30 min, take the supernatant and dry it (50 °C, vacuum degree: -0.088 MPa) to obtain hydrophilic modified graphene oxide (AS-GO).

[0129] (2) Preparation of amphiphilic modified graphene oxide TAS-GO: Mix 0.5 g of AS-GO intermediate, 2.0 g of hexadecyl silane coupling agent, and 100 g of ethanol / water mixture (m 乙醇 : m 水 = 1:1), react at 80 °C for 6 h; Then centrifuge at 4500 r / min for 30 min and discard the supernatant; Wash the lower layer solid 3 times with ethanol / water mixture (m 乙醇 : m 水 = 1:1) and deionized water respectively, and then dry it at 80 °C to obtain amphiphilic modified graphene oxide (TAS-GO).

[0130] (3) Weigh 0.9 g of sodium chloride and dissolve it in 100 mL of deionized water, heat it to 50 °C using a constant temperature water bath, then add 0.3 g of amphiphilic modified graphene oxide (TAS-GO) powder, and disperse it with an ultrasonic disperser for 30 min to obtain a soluble alkaline scale inhibitor.

[0131] Performance comparison:

[0132] Carry out a scale inhibition effect comparison experiment on the soluble alkaline scale inhibitors in Examples 1 to 6, Comparative Examples 1 to 18 and commercially available products (polyepoxysuccinic acid sodium, sodium polyaspartate, sodium polycarboxylate), including stability (30 °C, static), static salt inhibition rate and dynamic salt inhibition rate tests. The specific test methods are as follows:

[0133] (1)Static salt inhibition rate test method

[0134] a) Take 100 mL of tap water in a wide-mouth bottle, add an excessive amount of composite salt until the solution is supersaturated, place it in a 95 °C water bath and stir to dissolve for 30 min, and filter the undissolved salt particles in the solution while it is hot;

[0135] b) Take out the salt solution in a) and cool it at 10 °C for 24 h, transfer the solution to a suction funnel, filter for about 5 min, place the filter paper in a vacuum drying oven (0.09 MPa, 45 °C) to dry, weigh and calculate the mass of the precipitated salt scale as w 0 ;

[0136] c) Add a salt scale inhibitor to the salt solution described in a), dissolve it for 30 min first, then let it stand for 8 h and filter while it is hot, and repeat steps a) and b) for the rest, to obtain the salt scale mass as w 1 .

[0137] The formula for calculating the static salt scale inhibition rate is as follows:

[0138] Y sj = (w 0 -w 1 ) / w 0 ×100% ;

[0139] Among them, Y sj is the static salt scale inhibition rate, %; w 0 is the salt formation mass without adding a salt scale inhibitor, g;

[0140] w 1 is the salt formation mass with adding a salt scale inhibitor, g.

[0141] (2)Dynamic salt inhibition rate test method

[0142] Prepare a saturated solution of the target composite salt, heat it at 95 °C, stirring speed: 200 r / min, after complete dissolution, set different pump speeds to make the brine continuously circulate in the casing (pipe diameter 10 mm, pipe length 1 m), and the casing is cooled by circulating 10 °C tap water. Observe the salt formation on the sieve (100 mesh), and take timed photos for recording. Before each experiment, weigh the sieve put in and record the mass M 0 , after the experiment, take out the sieve, place the sieve in a desiccator to dry and weigh, and record the mass M of the sieve with attached salt crystals 1 ; Take out the salt scale attached to the pipe wall, filter and dry it, weigh and record the mass M 2 The salt formation amount is calculated according to the following formula: ;

[0143] wherein, Y sd is the dynamic salt 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 the inhibitor, g; M 2 is the mass of the salt scale on the pipe wall after the experiment without adding the inhibitor, g; M 1 ’ is the mass of the sieve after the experiment with adding the inhibitor, g; M 2 ’ is the mass of the salt scale on the pipe wall after the experiment with adding the inhibitor, g.

[0144] According to the above method, prepare composite salts NaHCO 3 :Na 2 CO 3 :NaCl = 63:27:10, 45:45:10, 27:63:10 saturated solutions, and compare the static and dynamic salt scale inhibition effects of different salt scale inhibitors. The test results are shown in Table 1 and Table 2.

[0145] Table 1 Comparison of the stability of the salt scale inhibitor and the static salt scale inhibition rate

[0146] .

[0147] Table 2 Comparison of the dynamic salt scale inhibition rate

[0148] .

[0149] Such as Figure 2 and Figure 3As 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.

[0150] 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.

[0151] 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; 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℃ 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; 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 for 2-3 times, it is dried at 80°C to obtain the amphiphilic modified graphene oxide TAS-GO; During the reaction of step S1, the mass ratio of graphene oxide GO to 6-amino-4-hydroxy-2-naphthalenesulfonic acid is 1:2 to 1:3; 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.

2. 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.

3. A soluble alkaline scale inhibitor as claimed in claim 1, 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.

4. A soluble alkaline scale inhibitor as claimed in claim 1, 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.

5. 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.

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