Bactericide for oil field as well as synthesis method and application of bactericide

Abstract

The invention belongs to the technical field of sewage treatment and relates to a bactericide for an oil field as well as a synthesis method and application thereof. The synthesis method comprises the following specific steps: adding N, N-dimethyl benzylamine, ethanol and dibromooctane into a reactor, adjusting the pH value to 8-9 by using sodium hydroxide, and heating and refluxing; 4, 6-dichloro-2-aminophenol is added into the mixed solution, the mixture is heated and subjected to a heat preservation reaction, and the pH is maintained to be 7-8 with sodium hydroxide during the reaction; and carrying out reduced pressure distillation until no solvent is distilled off at 70 DEG C, recrystallizing with ethyl acetate to obtain a solid, filtering and drying to obtain the product bactericide. The bactericide for the oil field has the advantages of simple synthesis process and high sterilization rate.

Description

Technical Field

[0001] The invention belongs to the technical field of sewage treatment and relates to a fungicide for oil fields and a synthesis method and application thereof. Background Art

[0002] As oilfield development enters the middle and late stages, the reservoir pressure gradually decreases during the development process, and crude oil production will also decrease. Therefore, it is necessary to take technical measures to replenish the energy of the formation in a timely manner. Secondary and tertiary oil recovery require the injection of a large amount of water into the formation to replenish the formation energy deficit. In water injection development, the water source is mainly sewage reinjection. Reinjection can not only replenish the formation energy, maintain stable oilfield production, and improve the recovery rate; it can also reduce the harm caused by sewage discharge to humans and the ecosystem, which is beneficial to environmental protection, and is therefore widely used.

[0003] However, since there are many types of microorganisms in the oil field reinjection water, the most common of which are sulfate-reducing bacteria (SRB), saprophytic bacteria (TGB) and iron bacteria (FB), the growth, metabolism and reproduction of these bacteria can cause corrosion and damage to drilling equipment, water injection pipelines and other metal materials, blockage of pipelines and water injection wells, reduce the porosity and permeability of the oil layer, hinder water injection and oil production, cause the water injection pressure to increase, and directly affect crude oil production.

[0004] Therefore, produced water must be sterilized before reinjection. There are many kinds of chemical agents used to kill or inhibit the growth of microorganisms. The extent of the killing effect on microorganisms varies depending on the toxicity of the chemical agent, the permeability into the cell and the type of microorganism. A chemical agent is toxic to a certain microorganism, but may have no effect on another microorganism. Some agents have a bactericidal effect at a slightly higher concentration, but at a certain low concentration, they have a stimulating effect on growth. Only by correctly selecting and using bactericides can the reproduction of harmful bacteria be effectively inhibited.

[0005] At present, the most commonly used fungicide in oil fields is dodecyl dimethyl benzyl ammonium chloride (1227), which is fast-acting and easy to operate. However, long-term use will cause bacteria to develop certain drug resistance, resulting in a significant decrease in the effectiveness of the agent.

[0006] CN103478164A discloses an oilfield sewage bactericide and a preparation method thereof, belonging to the field of oilfield chemical agents and preparation technology. The oilfield sewage bactericide is composed of nano titanium dioxide powder, a cross-linking agent, a surfactant and an oxidant mixed according to the following mass percentages: 10-15% nano titanium dioxide powder, 0.5-2% cross-linking agent, 5-10% surfactant, 5-10% oxidant, and the balance is water. The bactericide can be deposited on the pipe wall, bends, etc. with the liquid flow, and the main agent is slowly diluted. The drug effect is long-lasting and there is no corrosion to the pipeline. After 18 days of filling, the comprehensive bactericidal rate of sulfate-reducing bacteria, saprophytes and iron bacteria is still more than 90%, and the agent filling cycle is 15-25 days, which is 10-15 times that of ordinary agents, which greatly reduces the operation intensity and reduces the cost. However, the invention contains a large amount of titanium dioxide heavy metal, which will cause environmental damage, and the cost is high, and it is difficult to promote on a large scale. Summary of the invention

[0007] The present invention aims at the above-mentioned deficiencies of the prior art and provides an oilfield fungicide and its synthesis method and application. The oilfield fungicide of the present invention has the advantages of simple synthesis process and high sterilization rate.

[0008] One of the purposes of the present invention is to disclose a method for synthesizing an oilfield fungicide, the specific steps of the synthesis method are as follows:

[0009] (1) Add N,N-dimethylbenzylamine, ethanol and dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat to reflux;

[0010] (2) adding 4,6-dichloro-2-aminophenol to the above mixed solution, heating and keeping the mixture warm for reaction, and using sodium hydroxide to maintain the pH at 7-8;

[0011] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0012] In the present invention, preferably, based on 1 mole of N,N-dimethylbenzylamine, the dibromooctane and 4,6-dichloro-2-aminophenol are 0.8-1.2 moles and 0.8-1.2 moles, respectively; more preferably, based on 1 mole of N,N-dimethylbenzylamine, the dibromooctane and 4,6-dichloro-2-aminophenol are 0.9-1.1 moles and 0.9-1.1 moles, respectively.

[0013] In the present invention, preferably, the weight ratio of ethanol to N,N-dimethylbenzylamine in step (1) is 30-40:1.

[0014] In the present invention, preferably, the reflux reaction time in step (1) is 12-48h.

[0015] In the present invention, preferably, the heating temperature in step (2) is 50-60° C., and the insulation time is 4-8 h.

[0016] The synthesis reaction equation of the main component of the bactericide of the present invention is as follows:

[0017]

[0018]

[0019] Another object of the present invention is to disclose a fungicide for oil fields, wherein the main component molecular structure of the fungicide is as follows:

[0020]

[0021] The third object of the present invention is to disclose the application of the above-mentioned bactericide in oilfield wastewater treatment.

[0022] The bactericide of the present invention contains quaternary ammonium salt cations, which attract each other with the negatively charged bacterial surface through electrostatic force and are adsorbed on the bacterial body, thereby changing the permeability of the cell wall, causing the components in the bacterial cell to leak out and die, and the bactericide molecules can also penetrate into the inside of the bacterial body, making the bacterial protein inactive; the chlorophenol functional group is adsorbed on the cell wall and penetrates into the cytoplasm, killing the microorganism by precipitating the protein, and can react with the protein, enzyme and other biological macromolecules in the bacterial cell to generate oxidation reaction, thereby destroying the structure and function of these biological molecules; the benzyl and long-chain alkyl hydrophobic groups can be inserted into the lipid layer of the bacterial cell membrane, thereby changing the permeability of the cell membrane, and can also enter the inside of crude oil to kill the bacteria hidden in the crude oil.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] (1) The bactericide of the present invention has a broad spectrum and can kill SRB, TGB and FB in oily wastewater;

[0025] (2) The fungicide of the present invention has the advantages of low concentration and high efficiency. When the concentration is 5 mg / L, the bactericidal rates against SRB, TGB and FB are all above 89%. When the concentration is 15 mg / L, the bactericidal rates against SRB, TGB and FB are all 100%. DETAILED DESCRIPTION

[0026] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0027] The present invention will be further described below in conjunction with specific embodiments:

[0028] Embodiment 1:

[0029] (1) Add 0.1 mol N,N-dimethylbenzylamine, 405 g ethanol, and 0.08 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 12 h;

[0030] (2) Add 0.08 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 50°C, and keep the temperature for 4 hours, during which the pH is maintained at 7-8 with sodium hydroxide;

[0031] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0032] Embodiment 2:

[0033] (1) Add 0.1 mol N,N-dimethylbenzylamine, 420 g ethanol, and 0.12 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 16 h;

[0034] (2) Add 0.085 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 52°C, and keep the temperature for 8 hours, during which time the pH is maintained at 7-8 with sodium hydroxide;

[0035] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0036] Embodiment 3:

[0037] (1) Add 0.1 mol N,N-dimethylbenzylamine, 455 g ethanol, and 0.085 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 20 h;

[0038] (2) Add 0.12 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 58°C, and keep the temperature for 6 hours, during which the pH is maintained at 7-8 with sodium hydroxide;

[0039] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0040] Embodiment 4:

[0041] (1) Add 0.1 mol N,N-dimethylbenzylamine, 485 g ethanol, and 0.115 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 24 h;

[0042] (2) Add 0.115 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 60°C, and keep the temperature for 6 hours, during which the pH is maintained at 7-8 with sodium hydroxide;

[0043] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0044] Embodiment 5:

[0045] (1) Add 0.1 mol N,N-dimethylbenzylamine, 510 g ethanol, and 0.09 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 36 h;

[0046] (2) Add 0.11 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 55°C, and keep the temperature for 8 hours, during which the pH is maintained at 7-8 with sodium hydroxide;

[0047] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0048] Embodiment 6:

[0049] (1) Add 0.1 mol N,N-dimethylbenzylamine, 520 g ethanol, and 0.095 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 36 h;

[0050] (2) Add 0.1 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 55°C, and keep the temperature for 7 hours, during which the pH is maintained at 7-8 with sodium hydroxide;

[0051] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0052] Embodiment 7:

[0053] (1) Add 0.1 mol N,N-dimethylbenzylamine, 535 g ethanol, and 0.105 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 48 h;

[0054] (2) Add 0.095 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 60°C, and keep the temperature for 8 hours, during which the pH is maintained at 7-8 with sodium hydroxide;

[0055] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0056] Embodiment 8:

[0057] (1) Add 0.1 mol N,N-dimethylbenzylamine, 540 g ethanol, and 0.1 mol dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat under reflux for 48 h;

[0058] (2) Add 0.105 mol of 4,6-dichloro-2-aminophenol to the above mixed solution, heat to 60°C, and keep the temperature for 6 hours, during which the pH is maintained at 7-8 with sodium hydroxide;

[0059] (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

[0060] Example 9: Evaluation of sterilization rate

[0061] 500 ml of water sample from a joint station of an oil production plant in Shengli Oilfield containing SRB (sulfate-reducing bacteria), TGB (saprophytic bacteria), and FB (iron bacteria) were added to a series of narrow-mouthed bottles, and 5, 10, and 15 mg / L of bactericide (Examples 1-8) were added, shaken, placed in a 55°C oven, and sampled after 2 hours. The bacterial content was detected by the three-tube MPN method and the bactericidal rate was calculated. At the same time, dichlorophen and dodecyl dimethyl benzyl ammonium chloride were used as comparative examples 1 and 2, and the test results are shown in Tables 1, 2, and 3.

[0062] Table 1 SRB sterilization results (sterilization rate, %)

[0063] 5 10 15 Example 1 89.5 98.7 100 Example 2 89.5 98.7 100 Example 3 91.1 99.3 100 Example 4 93.3 99.3 100 Example 5 93.3 100 100 Example 6 97.7 100 100 Example 7 95.1 100 100 Example 8 96.9 100 100 Comparative Example 1 0 0 44.4 Comparative Example 2 9.6 59.1 81.8

[0064] From Table 1 we can see that:

[0065] (1) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 5 mg / L, the bactericidal rate against SRB was greater than 89%, with the highest reaching 96.9%; while the bactericidal rates of Comparative Examples 1 and 2 were 0 and 9.6%, respectively, which were significantly lower than those of the present invention;

[0066] (2) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 10 mg / L, the bactericidal rate against SRB reached more than 98%, with the highest reaching 100%; while the bactericidal rates of Comparative Examples 1 and 2 were 0 and 59.1%, respectively, which were significantly lower than those of the present invention;

[0067] (3) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 15 mg / L, the bactericidal rate against SRB reached 100%; while the bactericidal rates of Comparative Examples 1 and 2 were 44.4% and 81.8%, respectively, which were significantly lower than those of the present invention.

[0068] Table 2 TGB sterilization results (sterilization rate, %)

[0069] 5 10 15 Example 1 92.2 99.3 100 Example 2 93.3 99.3 100 Example 3 95.3 99.3 100 Example 4 95.9 100 100 Example 5 96.9 100 100 Example 6 97.3 100 100 Example 7 96.9 100 100 Example 8 97.8 100 100 Comparative Example 1 0 9.6 55.6 Comparative Example 2 0 59.1 81.8

[0070] From Table 2 we can see that:

[0071] (1) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 5 mg / L, the bactericidal rate against TGB was greater than 92%, with the highest reaching 97.8%; while the bactericidal rates of Comparative Examples 1 and 2 were both 0, which was significantly lower than that of the present invention;

[0072] (2) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 10 mg / L, the bactericidal rate against TGB reached more than 99%, with the highest reaching 100%. However, the bactericidal rates of Comparative Examples 1 and 2 were 9.6% and 59.1%, respectively, which were significantly lower than those of the present invention.

[0073] (3) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 15 mg / L, the bactericidal rate against TGB reached 100%; while the bactericidal rates of Comparative Examples 1 and 2 were 55.6% and 81.8%, respectively, which were significantly lower than those of the present invention.

[0074] Table 3FB sterilization results (sterilization rate, %)

[0075] 5 10 15 Example 1 93.3 100 100 Example 2 93.3 100 100 Example 3 94.7 100 100 Example 4 95.6 100 100 Example 5 96.9 100 100 Example 6 98.4 100 100 Example 7 98.7 100 100 Example 8 99.3 100 100 Comparative Example 1 0 44.4 59.1 Comparative Example 2 44.4 55.6 81.8

[0076] From Table 3 we can see that:

[0077] (1) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 5 mg / L, the bactericidal rate against FB was greater than 93%, with the highest reaching 99.3%; while the bactericidal rates of Comparative Examples 1 and 2 were 0 and 44.4%, respectively, which were significantly lower than those of the present invention;

[0078] (2) When the bactericide of the present invention (Examples 1-8) was used at a concentration of 10 mg / L, the bactericidal rate against FB reached 100%; while the bactericidal rates of Comparative Examples 1 and 2 were 44.4% and 55.6%, respectively, which were significantly lower than those of the present invention;

[0079] (3) When the fungicide of the present invention (Examples 1-8) was used at a concentration of 15 mg / L, the bactericidal rate against FB reached 100%; while the bactericidal rates of Comparative Examples 1 and 2 were 59.1% and 81.8%, respectively, which were significantly lower than those of the present invention.

[0080] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0081] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. In addition, the various different embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for synthesizing an oilfield fungicide, characterized in that: The specific steps of the synthetic method are as follows: (1) Add N,N-dimethylbenzylamine, ethanol and dibromooctane into a reactor, adjust the pH to 8-9 with sodium hydroxide, and heat to reflux; (2) adding 4,6-dichloro-2-aminophenol to the above mixed solution, heating and keeping the mixture warm for reaction, and using sodium hydroxide to maintain the pH at 7-8; (3) distilling under reduced pressure to 70°C until no solvent is distilled out, recrystallizing from ethyl acetate to obtain a solid, filtering and drying to obtain a fungicide product.

2. The method for synthesizing an oilfield bactericide according to claim 1, characterized in that: Based on 1 mole of N,N-dimethylbenzylamine, the dibromooctane and 4,6-dichloro-2-aminophenol are 0.8-1.2 moles and 0.8-1.2 moles respectively.

3. The method for synthesizing an oilfield bactericide according to claim 2, characterized in that: Based on 1 mole of N,N-dimethylbenzylamine, the dibromooctane and 4,6-dichloro-2-aminophenol are 0.9-1.1 mole and 0.9-1.1 mole respectively.

4. The method for synthesizing an oilfield bactericide according to claim 1, characterized in that: The weight ratio of ethanol to N,N-dimethylbenzylamine in step (1) is 30-40:

1.

5. The method for synthesizing an oilfield bactericide according to claim 1, characterized in that: The reflux reaction time in step (1) is 12-48h.

6. The method for synthesizing an oilfield bactericide according to claim 1, characterized in that: The heating temperature in step (2) is 50-60° C. and the insulation time is 4-8 hours.

7. A fungicide prepared according to the synthesis method according to any one of claims 1 to 6.

8. Use of the fungicide according to claim 7 in oilfield wastewater treatment.

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