Diesel-based gel as well as preparation method and application thereof
By synergistic crosslinking of aluminum ions and ferric ions in the diesel-based gel formulation, the problems of unstable gelation time and poor performance of existing gel systems are solved, achieving efficient and controllable gel preparation, which is suitable for sealing finished oil pipelines.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA UNIV OF PETROLEUM (EAST CHINA)
- Filing Date
- 2026-01-07
- Publication Date
- 2026-04-28
AI Technical Summary
Existing alkyl phosphate/crosslinker gel systems suffer from unstable gelation time, poor gel performance, and difficulty in application under harsh working conditions. Furthermore, the crosslinking process is difficult to control, leading to construction difficulties or low efficiency.
A diesel-based gel formulation is adopted, including diesel, alkyl phosphate, sodium aluminate and soluble ferric salt. Through the synergistic crosslinking effect of aluminum ions and ferric ions, the crosslinking ratio is optimized to form an efficient and controllable gel structure.
It significantly accelerates gel formation, improves the mechanical strength and stability of the gel, and forms a gel with stable structure, moderate viscosity, and enhanced elasticity, which meets the requirements of high-pressure sealing. Moreover, the preparation method is simple and easy to industrialize.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of oilfield chemical preparation technology, specifically relating to a diesel-based gel, its preparation method, and its application. Background Technology
[0002] Oil-based gels are widely used in the sequential transportation, pressure testing, plugging, and maintenance of refined oil pipelines due to their excellent oil phase compatibility and plugging performance. Among these, gel systems formed by the reaction of alkyl phosphates with crosslinking agents are a common choice. This system forms a three-dimensional network structure through the crosslinking reaction of alkyl phosphates and crosslinking agents, thereby encapsulating the oil phase and forming a gel with specific strength and viscoelasticity.
[0003] However, the existing alkyl phosphate / crosslinker gel system has obvious defects in practical applications: (1) The crosslinking process is difficult to control: the crosslinker is sensitive to conditions such as pH and temperature when it is undergoing crosslinking reaction, which leads to unstable gelation time. Either it is too fast, which makes construction difficult, or it is too slow, which affects the efficiency of operation; (2) Poor gel performance: when the proportion of crosslinker is too high, the gel network formed is too dense, which is brittle, easy to break, and has poor adhesion; when the proportion of crosslinker is too low, the degree of crosslinking is insufficient, the gel elasticity is weak, the strength is low, the stability is poor, and it cannot effectively seal; (3) The overall performance needs to be improved: traditional formulations are difficult to achieve the best balance between gelation speed, gel strength, structural stability and construction controllability, which limits their application in more severe working conditions. Summary of the Invention
[0004] Based on the above-mentioned technical problems, this invention proposes a diesel-based gel, its preparation method, and its application.
[0005] The technical solution adopted in this invention is: This invention provides a diesel-based gel comprising the following components in parts by weight: 90-110 parts diesel oil, 1.8-2.2 parts alkyl phosphate, 0.12-0.15 parts sodium aluminate, and 0.01-0.04 parts soluble ferric salt; wherein, diesel oil is used as the base solvent, alkyl phosphate as the gelling agent, sodium aluminate as the crosslinking agent, and soluble ferric salt as the crosslinking promoter.
[0006] Preferably, a diesel-based gel comprises the following components in parts by weight: 90-110 parts diesel oil, 1.8-2.2 parts alkyl phosphate, 0.13-0.14 parts sodium aluminate, and 0.028-0.04 parts soluble ferric salt.
[0007] Preferably, a diesel-based gel comprises the following components in parts by weight: 100 parts diesel oil, 2 parts alkyl phosphate, 0.132 parts sodium aluminate, and 0.028 parts soluble ferric salt.
[0008] Preferably, the soluble trivalent iron salt is ferric chloride or ferric nitrate.
[0009] Secondly, this invention provides a method for preparing a diesel-based gel, comprising the following steps: (1) Weigh the raw materials according to the above proportions and place the weighed diesel fuel in the mixing container; (2) Under stirring, add the weighed alkyl phosphate to the diesel oil and stir until completely dissolved to obtain mixture 1; (3) Prepare sodium aluminate solution by weighing out sodium aluminate; add the prepared sodium aluminate solution to mixture 1 obtained in step (2), stir until the mixture is uniform, and obtain mixture 2; (4) Prepare a soluble ferric salt solution by weighing out the soluble ferric salt; add the prepared soluble ferric salt solution to the mixture 2 obtained in step (3), and stir until the mixture is uniform to obtain mixture 3; (5) Allow the mixture 3 obtained in step (4) to stand and react to obtain diesel-based gel.
[0010] Preferably, in step (2): the stirring speed is 200-400 r / min and the time is 10-15 min.
[0011] Preferably, in step (3): the stirring speed is 400-600 r / min and the time is 15-20 min; the mass percentage concentration of sodium aluminate in the sodium aluminate solution is 5-15%.
[0012] Preferably, in step (4): the stirring speed is 400-600 r / min and the time is 5-10 min; the mass percentage concentration of soluble ferric salt in the soluble ferric salt solution is 5-15%.
[0013] Preferably, in step (5): the temperature of the static reaction is 20-30℃ and the time is 10-12h.
[0014] Finally, the present invention also provides an application of diesel-based gel in the sealing of refined oil pipelines.
[0015] The beneficial technical effects of the present invention are as follows: This invention utilizes sodium aluminate as a crosslinking agent and soluble ferric salt as a crosslinking promoter to achieve a synergistic crosslinking effect between aluminum ions and ferric ions, significantly accelerating the gelation rate and further improving the gelation properties, mechanical strength, and stability of the gel. Specific effects are as follows: (1) A highly efficient cross-linking agent was introduced: ferric ions (Fe3+) were innovatively introduced. 3+As a crosslinking promoter, it produces a synergistic crosslinking effect with aluminum ions, which significantly accelerates the gelation rate and makes the gelation process more controllable.
[0016] (2) The cross-linking ratio was optimized: The optimal mass ratio of sodium aluminate to alkyl phosphate was determined to be 1:15.2 through systematic experiments, and the optimal amount of ferric chloride was 1.4 wt% of the mass of alkyl phosphate. This effectively solved the brittleness problem under high cross-linking ratio and the insufficient elasticity problem under low cross-linking ratio, so that the gel has both good strength and hanging performance.
[0017] (3) Significantly improved gel performance: The final gel structure is stable, with moderate viscosity, significantly enhanced elasticity, and is not easily broken, which can meet the mechanical requirements of high-pressure pipeline sealing.
[0018] (4) Simple process and easy to implement: The preparation method is simple, the equipment requirements are low, all components are easy to obtain, and it is suitable for industrial production and on-site preparation. Detailed Implementation
[0019] The present invention provides a diesel-based gel comprising the following components in parts by weight: 90-110 parts diesel oil, 1.8-2.2 parts alkyl phosphate, 0.12-0.15 parts sodium aluminate, and 0.01-0.04 parts soluble ferric salt.
[0020] Secondly, the present invention also provides a method for preparing a diesel-based gel, comprising the following steps: (1) Prepare diesel phase: Take 100 parts by weight of diesel and place them in a mixing container; (2) Add gelling agent: Under stirring (200-400 r / min), add 2.0 parts by weight of alkyl phosphate to diesel oil and stir for 10-15 min until the mixture is uniform; (3) Add crosslinking agent: Slowly add sodium aluminate solution with an effective concentration of 0.12-0.15 parts by weight, and continue stirring (400-600 r / min) for 15-20 min to ensure that it is fully dispersed. The viscosity of the system begins to increase, indicating that the crosslinking reaction has started. (4) Add crosslinking agent: While stirring, add a soluble ferric salt solution with an effective concentration of 0.01-0.04 parts by weight, and stir continuously for 5-10 minutes at a speed of 400-600 r / min until the system becomes more viscous; (5) Let it stand to form a gel: Stop stirring and let the mixture stand at 25°C for about 10 hours to react. A stable high-strength gel will be formed.
[0021] In step (3) above, "sodium aluminate solution with an effective concentration of 0.12-0.15 parts by weight" refers to the sodium aluminate in the added sodium aluminate solution having a mass of 0.12-0.15 parts by weight. In step (4), "soluble ferric salt solution with an effective concentration of 0.01-0.04 parts by weight" refers to the soluble ferric salt in the added soluble ferric salt solution having a mass of 0.010-0.040 parts by weight. The mass percentage concentration of the two solutions is 5-15%, preferably 10%.
[0022] The present invention will be further described below with reference to specific embodiments. Unless otherwise specified, all chemical reagents used in the embodiments of the present invention are obtained through conventional commercial means.
[0023] In the following examples, the diesel fuel is Sinopec gas station No. 0 diesel.
[0024] Example 1 (1) Add 100 parts by weight of diesel oil to a clean mixing vessel; (2) Start stirring, control the speed at 300 r / min, slowly add 2.0 parts by weight of alkyl phosphate, stir for 12 min to fully dissolve it in diesel; (3) Increase the rotation speed to 500 r / min, slowly and evenly add sodium aluminate solution with an effective concentration of 0.132 parts by weight (mass percentage concentration of 10%), so that the mass ratio of sodium aluminate to alkyl phosphate is 1:15.2, stir vigorously for 18 min, and the system will gradually thicken. (4) Keep stirring and add ferric chloride solution with an effective concentration of 0.028 parts by weight (mass percentage concentration of 10%) so that ferric chloride accounts for 1.4% of the mass of alkyl phosphate. Control the speed to 500 r / min and continue stirring for 8 min. (5) Stop stirring, transfer the mixture to a container, and let it stand at 25°C for reaction; after about 10 hours, a uniform, stable diesel-based gel with good elasticity and strength is formed.
[0025] Example 2 The preparation method is the same as in Example 1. The difference is that a sodium aluminate solution with an effective concentration of 0.143 parts by weight is added, so that the mass ratio of sodium aluminate to alkyl phosphate is 1:14.
[0026] Example 3 The preparation method is the same as in Example 1. The difference is that a sodium aluminate solution with an effective concentration of 0.133 parts by weight is added, so that the mass ratio of sodium aluminate to alkyl phosphate is 1:15.
[0027] Example 4 The preparation method is the same as in Example 1. The difference is that a sodium aluminate solution with an effective concentration of 0.129 parts by weight is added, so that the mass ratio of sodium aluminate to alkyl phosphate is 1:15.5.
[0028] Example 5 The preparation method is the same as in Example 1. The difference is that a sodium aluminate solution with an effective concentration of 0.127 parts by weight is added, so that the mass ratio of sodium aluminate to alkyl phosphate is 1:15.8.
[0029] Example 6 The preparation method is the same as in Example 1. The difference is that a sodium aluminate solution with an effective concentration of 0.125 parts by weight is added, so that the mass ratio of sodium aluminate to alkyl phosphate is 1:16.
[0030] Example 7 The preparation method is the same as in Example 1. The difference is that a ferric chloride solution with an effective concentration of 0.036 parts by weight is added, so that the ferric chloride accounts for 1.8% of the alkyl phosphate by mass.
[0031] Example 8 The preparation method is the same as in Example 1. The difference is that a ferric chloride solution with an effective concentration of 0.022 parts by weight is added, so that the ferric chloride accounts for 1.1% of the alkyl phosphate by mass.
[0032] Example 9 The preparation method is the same as in Example 1. The difference is that a ferric chloride solution with an effective concentration of 0.01 parts by weight is added, so that the ferric chloride accounts for 0.5% of the alkyl phosphate by mass.
[0033] Comparative Example 1 The preparation method is the same as in Example 1. The difference is that ferric chloride solution is not added.
[0034] Comparative Example 2 The preparation method is the same as in Example 1. The difference is that the ferric chloride solution is replaced with a potassium dichromate solution with an effective concentration of 0.028 parts by weight (mass percentage concentration of 10%).
[0035] Comparative Example 3 The preparation method is the same as in Example 1. The difference is that the ferric chloride solution is replaced with a calcium chloride solution with an effective concentration of 0.028 parts by weight (mass percentage concentration of 10%).
[0036] The gelation state of Examples 1-9 and Comparative Examples 1-3 was observed and recorded. The experimental results are shown in Table 1.
[0037] Table 1. Formulation composition and gelation state experimental results of Examples 1-9 and Comparative Examples 1-3 As shown in Table 1, in Example 1, the diesel-based gel exhibited the best gelling performance when the mass ratio of sodium aluminate to alkyl phosphate was 1:15.2 and the amount of ferric chloride added was 1.4 wt% of the mass of alkyl phosphate. In Examples 2 and 3, the diesel-based gels exhibited brittleness due to the mass ratio of sodium aluminate to alkyl phosphate being higher than 1:15.2. In Examples 4-6, the diesel-based gels lacked elasticity due to the mass ratio of sodium aluminate to alkyl phosphate being lower than 1:15.2. In Example 7, the excessively rapid gelling speed and difficulty in controlling the gelling process, due to the amount of ferric chloride added being higher than 1.4 wt%, resulted in brittleness in the prepared diesel-based gel. In Examples 8 and 9, the amount of ferric chloride added was lower than 1.4 wt%. The addition of ferric chloride to alkyl phosphate slows down the gelation rate, resulting in insufficient elasticity of the prepared diesel-based gel. In particular, in Example 9, the addition of ferric chloride was only 0.5 wt%, which slowed down the gelation and led to poor stability of the prepared diesel-based gel. The above experimental results show that the optimal mass ratio of sodium aluminate to alkyl phosphate is 1:15.2, and the optimal addition of ferric chloride is 1.4 wt% of the mass of alkyl phosphate. Any deviation of this ratio from the optimal ratio will have an adverse effect on the gelation performance, mechanical strength and stability of the gel.
[0038] By comparing the above examples with the comparative examples, it can be seen that adding ferric chloride as a crosslinking agent accelerates the gelation speed, shortens the gelation time, makes the gelation process more controllable, and improves the elasticity, mechanical strength and stability of the gel. In Comparative Example 1, due to the absence of ferric chloride, the gelation was slow, and the prepared diesel-based gel had poor elasticity and stability. By comparing Comparative Examples 2 and 3 with Example 1, it can be seen that in Comparative Examples 2 and 3, the crosslinking agent ferric chloride was replaced with an equal amount of potassium dichromate solution and calcium chloride solution of effective concentration, respectively. Although potassium dichromate and calcium chloride are also commonly used crosslinking agents in oil-based gel systems, their addition to the oil-based gel system of the present invention results in slow gelation, and the prepared diesel-based gel has poor elasticity and stability. The above conclusions fully demonstrate that the trivalent iron ions (crosslinking agent) and aluminum ions (crosslinking agent) in the oil-based gel system of the present invention produce a synergistic crosslinking effect, which can significantly accelerate the gelation speed, thereby further improving the gelation performance, mechanical strength and stability of the gel. Replacing the crosslinking agent with other components (such as potassium dichromate solution or calcium chloride solution) will not achieve the technical effect of the present invention.
[0039] Any parts not mentioned in the above embodiments can be implemented by adopting or referencing existing technologies. Of course, the above description is not intended to limit the invention, and the invention is not limited to the above embodiments. Any changes, modifications, additions, or substitutions made by those skilled in the art within the scope of the invention should be considered within the protection scope of the invention.
Claims
1. A diesel-based gel, characterized in that, It includes the following components in parts by weight: 90-110 parts diesel oil, 1.8-2.2 parts alkyl phosphate, 0.12-0.15 parts sodium aluminate and 0.01-0.04 parts soluble ferric salt.
2. The diesel-based gel according to claim 1, characterized in that, It comprises the following components in parts by weight: 90-110 parts diesel oil, 1.8-2.2 parts alkyl phosphate, 0.13-0.14 parts sodium aluminate, and 0.028-0.04 parts soluble ferric salt.
3. The diesel-based gel according to claim 2, characterized in that, It comprises the following components in parts by weight: 100 parts diesel oil, 2 parts alkyl phosphate, 0.132 parts sodium aluminate and 0.028 parts soluble ferric salt.
4. The diesel-based gel according to claim 1, characterized in that, The soluble ferric salt is ferric chloride or ferric nitrate.
5. A method for preparing a diesel-based gel according to any one of claims 1-4, characterized in that, Includes the following steps: (1) Weigh the raw materials according to the above proportions and place the weighed diesel fuel in the mixing container; (2) Under stirring, add the weighed alkyl phosphate to the diesel oil and stir until completely dissolved to obtain mixture 1; (3) Prepare sodium aluminate solution by weighing out sodium aluminate; add the prepared sodium aluminate solution to mixture 1 obtained in step (2), stir until the mixture is uniform, and obtain mixture 2; (4) Prepare a soluble ferric salt solution by weighing out the soluble ferric salt; add the prepared soluble ferric salt solution to the mixture 2 obtained in step (3), and stir until the mixture is uniform to obtain mixture 3; (5) Allow the mixture 3 obtained in step (4) to stand and react to obtain diesel-based gel.
6. The method for preparing a diesel-based gel according to claim 5, characterized in that, In step (2): the stirring speed is 200-400 r / min and the time is 10-15 min.
7. The method for preparing a diesel-based gel according to claim 5, characterized in that, In step (3): the stirring speed is 400-600 r / min and the time is 15-20 min; the mass percentage concentration of sodium aluminate in the sodium aluminate solution is 5-15%.
8. The method for preparing a diesel-based gel according to claim 5, characterized in that, In step (4): the stirring speed is 400-600 r / min and the time is 5-10 min; the mass percentage concentration of soluble ferric salt in the soluble ferric salt solution is 5-15%.
9. The method for preparing a diesel-based gel according to claim 5, characterized in that, In step (5): the temperature of the static reaction is 20-30℃ and the time is 10-12h.
10. The application of a diesel-based gel as described in any one of claims 1-4 in the sealing of finished oil pipelines.