CN113372476A - Low-viscosity amphoteric polyacrylamide and preparation method thereof - Google Patents
Low-viscosity amphoteric polyacrylamide and preparation method thereof Download PDFInfo
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- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F120/00—Homopolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof
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Abstract
The invention provides low-viscosity amphoteric polyacrylamide and a preparation method thereof, and the low-viscosity amphoteric polyacrylamide is prepared by the following steps: dissolving acrylamide and an initiator in water to react to generate polyacrylamide; heating and hydrolyzing polyacrylamide under an alkaline condition to generate partially hydrolyzed polyacrylamide; adding an alkaline reagent and 3-chloro-2-hydroxypropyl trimethyl ammonium chloride into the partially hydrolyzed polyacrylamide solution to generate an amphoteric polyacrylamide mixed solution containing impurities; and adding an acidic reagent into the amphoteric polyacrylamide mixed solution to adjust the pH value of the solution to be neutral, adding an alcohol flocculating agent for flocculation, and performing suction filtration and drying on the precipitate to obtain the low-viscosity amphoteric polyacrylamide. The gel plugging agent prepared by mixing the polyacrylamide and the cross-linking agent has the characteristics of low viscosity and long gelling time, is suitable for profile control of remote wells in oil fields, can improve the crude oil recovery rate, and simultaneously has high adsorbability, and can effectively solve the problem of heavy metal pollution in sewage.
Description
Technical Field
The invention relates to the technical field of oilfield chemistry, in particular to low-viscosity amphoteric polyacrylamide and a preparation method thereof.
Background
Acrylamide is widely used in various industries as one of the most basic chemical industrial raw materials, however, as the demand of society is increasing, the traditional acrylamide cannot meet the social requirement, so that the acrylamide derivatives modified by chemistry are also widely used in the market, mainly comprising polyacrylamide, partially hydrolyzed polyacrylamide, anionic polyacrylamide, nonionic polyacrylamide, cationic polyacrylamide and the like, and the application of acrylamide is widened due to the appearance of the polymers. The cationic polymer with positively charged groups on the molecular chain can be widely applied to the industries of petroleum, spinning, printing and dyeing, environmental protection, paper making and the like in a paper published by Daqing Petroleum institute (2-methacryloyloxy-beta-hydroxypropyl) trimethyl ammonium chloride and acrylamide copolymerization reactivity) in the paper published by Daqing Petroleum institute, 2003(01) 26-28+ 111-. The invention patent CN201410770899.5 discloses a preparation method of acrylamide propyl trimethyl ammonium chloride cationic monomer homopolymer with high relative molecular mass, which prepares high molecular weight cationic polymer through polymerization reaction, and increases the application of polyacrylamide. Chinese patent CN201910817642.3 discloses a partially hydrolyzed polyacrylamide weak gel and a preparation method thereof, which reduces the gelling time of the partially hydrolyzed polyacrylamide gel by introducing anionic cellulose, and increases the salt resistance, the dispersibility and the like.
Although the current acrylamide substances are more in variety. But has shortcomings in solving the problems of remote well profile control and water plugging of oil fields and sewage treatment. Generally, the water plugging agent adopted in the oil field is polyacrylamide gel which has the characteristics of high viscosity, quick gelling and high strength, but the gel plugging agent with low viscosity, easy injection and slow gelling time is required on the remote well profile control water plugging, so that the commonly used acrylamide substance can not meet the requirement. Meanwhile, in sewage treatment, a single ionic polyacrylamide polymer is difficult to treat various heavy metal ions of sewage cleanly due to poor adsorbability, and the effect of adopting the amphoteric polyacrylamide polymer is better, however, at present, researches on simultaneously introducing anion and cation groups on polyacrylamide molecules are less, so that the application of acrylamide by hydrolyzing after acrylamide polymerization and introducing quaternary ammonium salt cations is of great significance.
Disclosure of Invention
The invention aims to provide a preparation method of low-viscosity amphoteric polyacrylamide (LHPAM), which is a polymer with low viscosity, strong adsorbability and long gelling time and can be used for solving the problems of profile control and water shutoff in oil fields and heavy metal pollution in sewage.
In order to achieve the above object, the technical solution of the present invention is as follows:
a low-viscosity amphoteric polyacrylamide is prepared by polymerizing acrylamide under the action of an initiator to generate polyacrylamide, hydrolyzing the polyacrylamide under an alkaline condition, and reacting the hydrolyzed polyacrylamide with a 3-chloro-2-hydroxypropyl trimethyl ammonium chloride monomer to generate the amphoteric polyacrylamide; according to the mass percent, the adding amount of the initiator is 2-10 percent of the adding amount of the acrylamide; the addition amount of the 3-chloro-2-hydroxypropyl trimethyl ammonium chloride is 5 to 20 percent of that of the acrylamide.
The preparation method of the low-viscosity amphoteric polyacrylamide LHPAM comprises the following steps:
s1, adding acrylamide and an initiator into water together for dissolving, and putting the dissolved acrylamide and the initiator into a water bath kettle for heating to generate a polyacrylamide solution;
s2, adding alkali into the polyacrylamide solution prepared in the S1, and then heating and hydrolyzing to generate a partially hydrolyzed polyacrylamide solution;
s3, adding an alkaline reagent and 3-chloro-2-hydroxypropyl trimethyl ammonium chloride into the partially hydrolyzed polyacrylamide solution prepared in the S2, and heating to react to generate an amphoteric polyacrylamide mixed solution containing impurities;
s4, adding an acidic reagent into the amphoteric polyacrylamide mixed solution containing the impurities prepared in the S3 to adjust the pH of the solution to be neutral, adding an alcohol flocculating agent for flocculation, and performing suction filtration and drying on precipitates to obtain the low-viscosity amphoteric polyacrylamide.
Further, in step S1, the mass concentration of the acrylamide solution is 5% to 10%, and the initiator is one or more of a peroxide initiator and a redox initiator. The peroxide is ammonium persulfate or potassium persulfate.
Further, in step S2, the reaction temperature for generating polyacrylamide is 50-60 ℃, and the reaction time is 30-60 min.
Further, in step S2, the alkali is one or more of sodium hydroxide and potassium hydroxide. The addition amount of the alkali is 5-20% of the addition amount of the acrylamide by mass. According to the determination, when the mass concentration of the acrylamide solution is 5-10%, after 5-20% of acrylamide added amount of alkali is added, the pH value of the solution is 12-14.
Further, in step S3, the reaction temperature is 80-90 ℃ and the reaction time is 30-60 min.
Further, in step S3, the alkaline reagent is one or more of sodium hydroxide, potassium hydroxide, etc., and after the alkaline reagent is added to the partially hydrolyzed polyacrylamide solution, the partially hydrolyzed polyacrylamide solution is mainly reacted with 3-chloro-2-hydroxypropyltrimethylammonium chloride, and the reaction product is then reacted with hydrolyzed polyacrylamide. According to the mass, the adding amount of the alkaline reagent is 2-10% of the adding amount of the acrylamide.
Further, in the step S4, the reaction temperature is 45-60 ℃, and the reaction time is 15-18 h.
Further, in the step S4, the acidic reagent is one or more of acetic acid, hydrochloric acid, and sulfuric acid, the flocculant is one or more of ethanol and propanol, and the volume usage of the flocculant is 3-5 times of the total volume of the solution. The acidic reagent is mainly used for removing redundant alkali and adjusting the pH value to be about 7, the flocculating agent is used for extracting LHPAM in the solution, and the flocculating agent is less in dosage and is not easy to extract.
Has the advantages that: the invention introduces cation on the molecule of partially hydrolyzed polyacrylamide, thereby synthesizing the amphoteric polyacrylamide. Compared with other existing polyacrylamide modification technologies, the polyacrylamide gel has the advantages that the polyacrylamide gel is used as a polymer to reduce the viscosity of polyacrylamide, is used as a sewage treatment agent to increase the adsorbability of the polyacrylamide, and is used as a gel plugging agent to solve the problem of profile control and water plugging of a remote well.
Drawings
FIG. 1 is an infrared contrast plot of HPAM and LHPAM;
FIG. 2 is a graph comparing the viscosity of HPAM and LHPAM at different concentrations;
fig. 3 is a graph comparing the viscosity of LHPAM and HPAM at 60 ℃ for different time periods.
Detailed Description
The present invention will now be described more fully hereinafter with reference to the accompanying examples, in which some, but not all embodiments of the invention are shown.
In the 3-chloro-2-hydroxypropyltrimethylammonium chloride solution of this example, the mass concentration of 3-chloro-2-hydroxypropyltrimethylammonium chloride was 60%.
The invention is further described below with reference to the following examples:
example 1 preparation method of Low-viscosity amphoteric Polyacrylamide (LHPAM)
(1) The synthesis of LHPAM comprises the following specific steps
Step 1, pouring 5g of acrylamide into 95g of pure water, and adding 0.1g of ammonium persulfate after complete dissolution;
step 2, putting the beaker containing the solution into a water bath kettle at 60 ℃, reacting for 30min, and adding 0.5g of sodium hydroxide;
step 3, adjusting the temperature to 90 ℃, stirring and reacting for 60min to obtain partially Hydrolyzed Polyacrylamide (HPAM), and then adding 0.5ml of 3-chloro-2-hydroxypropyl trimethyl ammonium chloride and 0.1g of sodium hydroxide;
step 4, reacting at 50 ℃ for 18h, and finally adding hydrochloric acid to adjust the pH of the solution to be neutral;
and 5, flocculating by using absolute ethyl alcohol with the volume being 3 times that of the polymer, and filtering, drying and crushing to obtain the polymer LHPAM.
The infrared comparison graph of HPAM and LHPAM is shown in figure 1, and the comparison shows that the characteristic absorption peak of trimethyl quaternary ammonium salt (-N + (CH3)3Cl-1) appears at 1454cm-1, which is the absorption peak of C-N bond stretching vibration, and the peak at 1565cm-1 is caused by secondary amide N-H bending vibration, which indicates that N-H is replaced by N-R, thereby proving that LHPAM has been synthesized successfully.
Comparing the viscosities of HPAM and LHPAM at different concentrations at room temperature and 60 deg.C, the results are shown in FIG. 2, and it is found that the viscosity of LHPAM is higher than that of HPAM at room temperature and lower than that of HPAM at 60 deg.C.
The viscosity change of the LHPAM and the HPAM was continuously observed at 60 ℃, and as a result, as shown in fig. 3, it was found that initially, the viscosity of the HPAM was less than that of the LHPAM, the viscosity of the LHPAM was less than that of the HPAM after 1d, and the viscosity of the LHPAM decreased at a much higher rate than that of the HPAM.
Performance test 1LHPAM and HPAM application comparison as gel blocking agent
The implementation steps of taking LHPAM and HPAM as the gel blocking agent are as follows:
(1) respectively preparing LHPAM and HPAM solutions with the concentrations of 1%, 2%, 3%, 4% and 5%, and placing for a period of time at 60 ℃;
(2) preparing 20g of chromium acetate solution from 0.96g of sodium acetate and 2.7g of chromium chloride, and standing at 60 ℃ for a period of time;
(3) adding LHPAM and HPAM solutions with different concentrations according to the chromium ion concentration of 0.2%, respectively placing at 30 deg.C, 60 deg.C, 90 deg.C, and observing its gelling time. The gelling times of the LHPAM and HPAM solutions are compared in Table 1. As can be seen from table 1, the gelling time of LHPAM is longer than that of HPAM, and the gelling time becomes slower and slower with increasing temperature, and becomes longer and longer with decreasing viscosity, and at a concentration of 1%, both LHPAM and HPAM do not gel.
TABLE 1 comparison table of gelation time of LHPAM and HPAM solutions
Performance test 2 LHPAM and HPAM application comparison as sewage treatment agent
The implementation steps are as follows:
(1) preparing 50ml of 0.5% chromium acetate solution;
(2) 10 drops of LHPAM and HPAM solutions with the concentration of 3% are respectively added into the chromium acetate solution, and the color change of the solution is observed after the solution is uniformly stirred. The experimental results are shown in table 2, and it can be seen from table 2 that LHPAM has strong adsorbability, and can adsorb heavy metal ions in water, and HPAM basically cannot adsorb metal ions.
TABLE 2 comparison of flocculation effects of LHPAM and HPAM
The present invention has been disclosed in the foregoing in terms of preferred embodiments, but it will be understood by those skilled in the art that these embodiments are merely illustrative of the present invention and should not be construed as limiting the scope of the present invention. Further modifications are possible without departing from the principles of the invention and these modifications are to be considered as protection of the invention.
Claims (9)
1. The low-viscosity amphoteric polyacrylamide is characterized in that acrylamide is polymerized under the action of an initiator to generate polyacrylamide, and the polyacrylamide is hydrolyzed under an alkaline condition and then is introduced with a 3-chloro-2-hydroxypropyl trimethyl ammonium chloride monomer for reaction to generate the low-viscosity amphoteric polyacrylamide; according to the mass percent, the adding amount of the initiator is 2-10 percent of the adding amount of the acrylamide; the addition amount of the 3-chloro-2-hydroxypropyl trimethyl ammonium chloride is 5 to 20 percent of that of the acrylamide.
2. A method for preparing the low viscosity amphoteric polyacrylamide of claim 1, comprising the steps of:
s1, adding acrylamide and an initiator into water together for dissolving, and putting the dissolved acrylamide and the initiator into a water bath kettle for heating to generate polyacrylamide;
s2, adding alkali into the polyacrylamide solution, heating and hydrolyzing to generate partially hydrolyzed polyacrylamide;
s3, adding an alkaline reagent and 3-chloro-2-hydroxypropyl trimethyl ammonium chloride into the partially hydrolyzed polyacrylamide solution, and heating to generate an amphoteric polyacrylamide mixed solution containing impurities;
s4, adding an acidic reagent into the amphoteric polyacrylamide mixed solution containing impurities to adjust the pH value of the solution to be neutral, adding an alcohol flocculating agent for flocculation, and performing suction filtration and drying on precipitates to obtain low-viscosity amphoteric polyacrylamide.
3. The method for preparing low viscosity amphoteric polyacrylamide according to claim 2, wherein: in the step S1, the initiator is one or more of a peroxide initiator and a redox initiator, the reaction temperature for generating polyacrylamide is 50-60 ℃, and the reaction time is 30-60 min.
4. The method for preparing low viscosity amphoteric polyacrylamide according to claim 3, wherein: the peroxide initiator is ammonium persulfate or potassium persulfate.
5. The method for preparing low viscosity amphoteric polyacrylamide according to claim 2, wherein: in the step S2, the reaction temperature of the polyacrylamide hydrolysis is 80-90 ℃, and the reaction time is 30-60 min.
6. The method for preparing low viscosity amphoteric polyacrylamide according to claim 2, wherein: in the step S2, the alkali is one or more of sodium hydroxide and potassium hydroxide, and the addition amount of the alkali is 5-20% of the addition amount of the acrylamide by mass.
7. The method for preparing low viscosity amphoteric polyacrylamide according to claim 2, wherein: in the step S3, the reaction temperature of the generated amphoteric polyacrylamide mixed solution containing the impurities is 45-60 ℃, and the reaction time is 15-18 h.
8. The method for preparing low viscosity amphoteric polyacrylamide according to claim 2, wherein: in step S3, the alkaline reagent is one or more of sodium hydroxide, potassium hydroxide, etc., and the amount of the alkaline reagent added is 2% to 10% of the amount of the acrylamide added.
9. The method for preparing low viscosity amphoteric polyacrylamide according to claim 2, wherein: in step S4, the acidic reagent is one or more of acetic acid, hydrochloric acid and sulfuric acid, and the flocculating agent is one or more of ethanol and propanol.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115926073A (en) * | 2022-12-02 | 2023-04-07 | 西南石油大学 | Nano calcium carbonate modified acrylamide amphoteric copolymer and preparation method thereof |
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Non-Patent Citations (3)
| Title |
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| 游霞等: "盐酸返滴定测定3-氯-2-羟丙基三甲基氯化铵含量的方法研究", 《四川化工》 * |
| 熊青山: "《石油工程专业实验指导书》", 31 October 2012, 中国石油大学出版社 * |
| 黄晓东等: "《纺织有机化学》", 31 March 2014, 东华大学出版社 * |
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| CN115926073A (en) * | 2022-12-02 | 2023-04-07 | 西南石油大学 | Nano calcium carbonate modified acrylamide amphoteric copolymer and preparation method thereof |
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