Efficient mesoporous purifying agent as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of oilfield chemistry, and particularly relates to a high-efficiency mesoporous purifying agent as well as a preparation method and application thereof. The preparation method of the efficient mesoporous purifying agent comprises the following steps: (1) dispersing a silicon source, a silane dispersant and a crystal growth control agent in a solvent to form a mixed solution; (2) adding acid to adjust pH, and heating and stirring to obtain dispersion liquid; (3) after stirring is stopped, the dispersion liquid is subjected to high-frequency radiation induced crystallization treatment, and dispersion liquid of the modified mesoporous purifying agent is obtained; and (4) washing, filtering and drying the dispersion liquid of the modified mesoporous purifying agent to obtain the efficient mesoporous purifying agent. The high-efficiency mesoporous purifying agent has the specific surface area of 200-300 m < 2 > / g, the VOC detection value of 0-100 ppm, the pore diameter of 5-12 nm, small particles and the characteristic of high adsorption, can be used as an adsorption decolorizing agent, is directly added into recycled oil and is used for decolorizing and deodorizing the recycled oil, and the quality of an oil product is ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of oilfield chemistry, and in particular relates to a high-efficiency mesoporous purifier and a preparation method and application thereof. Background Art

[0002] Marine oil and gas exploration and development is in a stage of vigorous development in China. A large amount of experience in oil and gas drilling operations has been accumulated in the shallow waters of the Bohai Bay and the deep and ultra-deep waters of the South China Sea. A series of key technologies suitable for China's marine oil and gas drilling operations have been formed, laying a good foundation for the development of China's marine oil and gas engineering technology.

[0003] However, in oil and gas field drilling operations, the thermal treatment of non-aqueous drilling fluids / cuttings for recycling oil products will produce a strong pungent odor, which affects the working environment and the safety and health of personnel. At present, the mainstream methods for oil purification include chemical washing, oxidation, biological methods and adsorption. Compared with chemical washing, oxidation and biological treatment methods, the adsorption method can retain odorous substances on the surface of the adsorbent (solid), and has the advantages of high efficiency, low energy consumption, simple operation, recyclability, and no effect on oil quality. Therefore, it has become an effective technology for removing odor substances in oil. Silicon-based mesoporous materials have the characteristics of large specific surface area, high porosity, high temperature resistance, corrosion resistance, easy recycling, small and uniform pore size, and extremely strong adsorption capacity. Volatile organic compounds (VOCs) in the recovered oil can be adsorbed inside or on the surface of the pores to remove VOCs. In addition, due to the existence of specific mesoporous adsorption characteristics, the chromaticity of the recovered oil can be effectively reduced, so that it can be reused after treatment. Therefore, silicon-based mesoporous materials are new functional materials with good prospects for decolorization and deodorization.

[0004] The main preparation methods of silicon-based mesoporous materials include the gas phase method using silane halides as raw materials; the chemical precipitation method using sodium silicate and inorganic acid as raw materials; and the sol-gel method and microemulsion method using silicate esters as raw materials. Among these methods, the gas phase method has expensive raw materials, high equipment requirements, long production process, and high energy consumption; the sol-gel method has expensive raw materials and a long preparation time; and the microemulsion method has high costs, organic matter is difficult to remove, and it is easy to pollute the environment. Compared with the above three methods, the chemical precipitation method has the advantages of a wide source of raw materials, low price, low energy consumption, simple process, and easy industrialization, but it also has the problem of uneven product pore size or a wide distribution range, which affects the purification effect. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a high-efficiency mesoporous purifier and a preparation method and application thereof. A mesoporous purifier with a smaller pore size is obtained through an efficient microwave-assisted sulfuric acid precipitation refining method. At the same time, it is ensured that the mesoporous purifier has a higher VOC removal rate. The entire preparation process is simple, with significant economic benefits, and is suitable for large-scale industrial production.

[0006] The technical solution of the present invention is as follows:

[0007] A method for preparing a high-efficiency mesoporous purifier comprises:

[0008] (1) dispersing a silicon source, a silane dispersant, and a crystal growth control agent in a solvent to form a mixed solution;

[0009] (2) adding acid to adjust the pH, heating and stirring to obtain a dispersion;

[0010] (3) after stopping stirring, subjecting the dispersion to a high-frequency radiation-induced crystallization treatment to obtain a dispersion of a modified mesoporous purifier;

[0011] (4) Washing, filtering and drying the dispersion of the modified mesoporous purifier to obtain a high-efficiency mesoporous purifier.

[0012] In the above-mentioned method for preparing the high-efficiency mesoporous purifier, the mass ratio of the silicon source, the silane dispersant, the crystal growth controller and the solvent is 1: (0.01-1): (0.01-0.5): (4-25).

[0013] In the preparation method of the above-mentioned high-efficiency mesoporous purifier, the silicon source is one or more of ethyl orthosilicate, trichlorosilane, silicon tetrachloride, sodium silicate and methyltrimethylsilane.

[0014] In the preparation method of the above-mentioned high-efficiency mesoporous purifier, the silane dispersant is one or more of sodium hexametaphosphate, sodium chloride, sodium sulfate, sodium pyrophosphate, sodium dodecyl sulfonate and sodium dodecylbenzene sulfonate.

[0015] In the preparation method of the above-mentioned high-efficiency mesoporous purifier, the crystal growth controller is one or more of ethanol, isopropanol, glycerol, n-butanol, propylene oxide and dichloromethane.

[0016] In the preparation method of the above-mentioned high-efficiency mesoporous purifier, the solvent is one or more of water, acetic acid, ethanol, formic acid, acetone and glycerol.

[0017] The method for preparing the above-mentioned high-efficiency mesoporous purifier comprises, in step (2), adjusting the pH value of the mixed solution to 2.0 to 7.0 using sulfuric acid having a concentration of 0.526 to 4.030 mol / L.

[0018] In the preparation method of the above-mentioned high-efficiency mesoporous purifier, the heating and stirring temperature is 30° C. to 60° C., the rotation speed is 100 to 500 rpm, and the stirring time is 3 to 8 hours.

[0019] In the preparation method of the above-mentioned high-efficiency mesoporous purifier, the output power during the high-frequency radiation-induced crystallization treatment is 200 to 800 W, and the crystallization time is 0.5 to 1 hour.

[0020] The preparation method of the above-mentioned high-efficiency mesoporous purifier, the washing includes one or more of water washing and alcohol washing; the filtration includes one or more of vacuum filtration, pressure filtration, centrifugal filtration and squeeze filtration; the drying includes one or more of oven drying, vacuum drying, freeze drying, supercritical CO2 drying and spray drying.

[0021] The present invention also provides a high-efficiency mesoporous purifier, which is prepared by the above-mentioned preparation method.

[0022] The above-mentioned high-efficiency mesoporous purifier has a specific surface area of ​​200 to 300 m 2 / g, VOC detection value is 0-100ppm, and pore size is 5-12nm.

[0023] The invention also provides application of the high-efficiency mesoporous purifier in purifying recovered oil.

[0024] The high-efficiency mesoporous purifier and its preparation method of the present invention have the following beneficial effects compared with the prior art:

[0025] (1) The preparation method of the high-efficiency mesoporous purifier of the present invention weakens the self-polymerization process of silicic acid by adding a certain amount of silane dispersant and crystal growth controller in a mixed solvent, so that the silicic acid can be well dispersed in the system and present a stable state. By controlling the temperature, pH value, concentration and time of the reaction process, and adopting a high-frequency radiation-induced crystallization method, the mesoporous purifier can maintain a high specific surface area and a high VOC removal rate. The method meets environmental protection standards, reduces environmental pollution, has significant economic benefits, optimizes the process flow, and is suitable for large-scale industrial production;

[0026] (2) The high-efficiency mesoporous purifier of the present invention has a specific surface area of ​​200 to 300 m 2 / g, VOC detection value is 0-100ppm, pore size is 5-12nm, small particles, with high adsorption characteristics, can be used as an adsorption decolorizing agent, directly added to the recovered oil, used for decolorization and deodorization of recovered oil to ensure the quality of the oil. DETAILED DESCRIPTION

[0027] In order to fully understand the purpose, features and effects of the present invention, the present invention is described in detail through the following specific embodiments. Except for the following contents, the process method of the present invention adopts conventional methods or devices in the art. Unless otherwise specified, the following terms have the meanings commonly understood by those skilled in the art.

[0028] When a numerical range is disclosed herein, the above range is considered to be continuous and includes the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0029] Specifically, the preparation method of the high-efficiency mesoporous purifier provided by the present invention comprises: (1) dispersing a silicon source, a silane dispersant and a crystal growth controller in a solvent to form a mixed solution; (2) adding an acid to adjust the pH, heating and stirring to obtain a dispersion; (3) after stopping stirring, subjecting the dispersion to a high-frequency radiation-induced crystallization treatment to obtain a dispersion of a modified mesoporous purifier; (4) washing, filtering and drying the dispersion of the modified mesoporous purifier to obtain a high-efficiency mesoporous purifier.

[0030] The preparation method of the high-efficiency mesoporous purifier of the present invention can ensure that it has a good decolorization effect on oil products such as recycled oil while specifically designing the mesoporous purifier material, and has excellent adsorption performance for odorous VOCs present in the oil products, thereby ensuring the quality of the oil products.

[0031] In step (1), the silane dispersant and the crystal growth controller weaken the self-polymerization process of silicic acid, so that it can be well dispersed in the system and present a stable state.

[0032] In some preferred embodiments, the mass ratio of the silicon source, the silane dispersant, the crystal growth controller and the solvent is 1:(0.01-1):(0.01-0.5):(4-25).

[0033] According to practice, when the mass ratio of the silicon source is too small, the silicon-based particles in the solution mainly participate in the crystal nucleus growth process. At this time, the crystal nucleus growth rate is greater than the crystal nucleus formation rate, and the silica particles formed in the solution are larger in size, have a greater degree of aggregation, and have a smaller specific surface area. When the mass ratio of the silicon source is too large, the crystal nucleus growth rate and the crystal nucleus formation rate increase at the same time, but the former increases more, resulting in a decrease in the average silica particle size. However, due to the continuous increase in the number of silica nucleus particles, the probability of collision and bonding between silica particles increases, making it easy to form silica particles with a higher aggregation structure.

[0034] When the mass ratio of the silane dispersant is too small, the silica particles in the solution are not easy to precipitate and aggregate, and the silica yield is reduced; when the mass ratio of the silane dispersant is too large, the excess silane dispersant will be wrapped inside the precipitate, causing its particle size to increase, and the excess electrolyte will block the internal pores of the silica, reducing its specific surface area.

[0035] When the mass ratio of the crystal growth controller is too small, the secondary particles formed in the solution are easy to aggregate, making it easy for the silica colloidal solution to aggregate into silica gel; when the mass ratio of the crystal growth controller is too large, during the drying and precipitation process, the silica particles lose water, resulting in silicon-oxygen combination to form tertiary particles, making the particles coarse and losing activity.

[0036] Further preferably, the mass ratio of the silicon source, the silane dispersant, the crystal growth controller and the solvent is 1:(0.05-1):(0.01-0.1):(4-10).

[0037] In some preferred embodiments, the silicon source is one or more of tetraethyl orthosilicate, trichlorosilane, silicon tetrachloride, sodium silicate and methyltrimethylsilane; the silane dispersant is one or more of sodium hexametaphosphate, sodium chloride, sodium sulfate, sodium pyrophosphate, sodium dodecyl sulfonate and sodium dodecylbenzene sulfonate; the crystal growth controller is one or more of ethanol, isopropanol, glycerol, n-butanol, propylene oxide and dichloromethane; the solvent is one or more of water, acetic acid, ethanol, formic acid, acetone and glycerol.

[0038] In step (2), in the alkali solution and the dilute acid solution, H4SiO + With negative valence H3SiO4 - :Polymerize to form silicate dimer. Silicate dimer reacts with H3SiO4 - The reaction polymerizes into trimers, tetramers and other polysilicic acids. While forming polysilicic acid, Si-O-Si chains can also form multi-branched polysilicic acids in the middle of the chain, and polysilicic acid further polymerizes to form SiO2 sol.

[0039] In some preferred embodiments, the pH value of the mixed solution is adjusted to 2.0-7.0 using sulfuric acid with a concentration of 0.526-4.030 mol / L, and then stirred at 30°C-60°C and a rotation speed of 100-500 rpm for 3-8 hours to reduce the concentration of orthosilicic acid, slow down the polymerization rate, and prolong the gel time.

[0040] In step (3), high-frequency radiation-induced crystallization treatment can promote uniform dispersion of silica particles and reduce agglomeration, thereby obtaining smaller and more uniform particles; in this process, the solution is rapidly and evenly heated, crystals are rapidly formed, and the crystallinity of silica is improved.

[0041] The present invention adopts a microwave digestion apparatus to carry out high-frequency radiation-induced crystallization treatment on the dispersion.

[0042] In some preferred embodiments, the output power of the high-frequency radiation-induced crystallization treatment is 200 to 800 W, and the crystallization time is 0.5 to 1 hour, thereby enabling the mesoporous purifier to maintain a high specific surface area and a high VOC removal rate.

[0043] Optionally, the present invention adopts 200W output power high frequency radiation induced crystallization, 500W output power high frequency radiation induced crystallization or 800W output power high frequency radiation induced crystallization.

[0044] In step (4), the modified mesoporous purifier and the impurities therein can be separated by washing, filtering and drying the dispersion of the modified mesoporous purifier to obtain a modified mesoporous purifier with qualified ingredients.

[0045] In some preferred embodiments, the washing comprises one or more of water washing and alcohol washing; the filtration comprises one or more of vacuum filtration, pressure filtration, centrifugal filtration and squeeze filtration; the drying comprises one or more of oven drying, vacuum drying, freeze drying, supercritical CO2 drying and spray drying.

[0046] On the other hand, the present invention also provides a high-efficiency mesoporous purifier, which is prepared by the above-mentioned preparation method.

[0047] The high-efficiency mesoporous purifier obtained by the method of the present invention has a specific surface area of ​​200 to 300 m 2 / g, VOC detection value is 0-100ppm, pore size is 5-12nm. It can be used as a recycled oil adsorption decolorizing agent, with good oil decolorization effect and VOC removal rate, and the purifier can be regenerated multiple times, further reducing the processing cost, and is an ideal recycled oil purification agent.

[0048] Example

[0049] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions. The raw materials used in the following examples are all conventionally purchased.

[0050] Example 1

[0051] A method for preparing a high-efficiency mesoporous purifier for the petroleum industry comprises the following steps:

[0052] (1) dispersing tetraethyl orthosilicate, sodium sulfate and n-butanol in water to form a mixed solution, wherein the mass ratio of tetraethyl orthosilicate, sodium sulfate, n-butanol and water is 1:0.01:0.08:4;

[0053] (2) adjusting the pH value of the mixed solution to 6.0 with sulfuric acid having a concentration of 2.5 mol / L, and stirring at a speed of 300 rpm at 40° C. for 6 h. After the stirring stops, subjecting the dispersion to high-frequency radiation with an output power of 500 W to induce crystallization for 1 h, thereby obtaining a dispersion of modified mesoporous silica-based materials;

[0054] (3) The dispersion was repeatedly washed with ethanol for 3 times;

[0055] (4) vacuum filtering the dispersion repeatedly washed with ethanol;

[0056] (5) Place the filtered sample in an oven and dry it at 60°C;

[0057] (6) The dried sample is crushed to obtain a powdery mesoporous purifier.

[0058] Example 2

[0059] A method for preparing a high-efficiency mesoporous purifier for the petroleum industry comprises the following steps:

[0060] (1) dispersing tetraethyl orthosilicate, sodium hexametaphosphate and n-butanol in water to form a mixed solution, wherein the mass ratio of tetraethyl orthosilicate, sodium hexametaphosphate, n-butanol and water is 1:0.02:0.01:5;

[0061] (2) adjusting the pH value of the mixed solution to 5.0 with sulfuric acid having a concentration of 4.030 mol / L, and stirring at 45° C. and 350 rpm for 8 h. After the stirring stops, subjecting the dispersion to high-frequency radiation with an output power of 200 W to induce crystallization for 1 h, thereby obtaining a dispersion of modified mesoporous silica-based materials;

[0062] (3) Wash the dispersion repeatedly with water for 3 times;

[0063] (4) vacuum filtering the dispersion repeatedly washed with water;

[0064] (5) Place the filtered sample in an oven and dry it at 90°C;

[0065] (6) The dried sample is crushed to obtain a powdery mesoporous purifier.

[0066] Example 3

[0067] A method for preparing a high-efficiency mesoporous purifier for the petroleum industry comprises the following steps:

[0068] (1) dispersing tetraethyl orthosilicate, sodium chloride and n-butanol in water to form a mixed solution, wherein the mass ratio of tetraethyl orthosilicate, sodium chloride, n-butanol and water is 1:0.01:0.03:4;

[0069] (2) adjusting the pH value of the mixed solution to 7.0 with sulfuric acid having a concentration of 0.526 mol / L, and stirring at 400 rpm for 5 h at 50° C., and after stopping the stirring, subjecting the dispersion to high-frequency radiation with an output power of 200 W for 1 h to induce crystallization, thereby obtaining a dispersion of modified mesoporous silica-based materials;

[0070] (3) The dispersion was repeatedly washed with ethanol for 3 times;

[0071] (4) vacuum filtering the dispersion repeatedly washed with ethanol;

[0072] (5) Place the filtered sample in an oven and dry it at 120°C;

[0073] (6) The dried sample is crushed to obtain a powdery mesoporous purifier.

[0074] Example 4

[0075] A method for preparing a high-efficiency mesoporous purifier for the petroleum industry comprises the following steps:

[0076] (1) dispersing tetraethyl orthosilicate, sodium pyrophosphate and n-butanol in water to form a mixed solution, wherein the mass ratio of tetraethyl orthosilicate, sodium pyrophosphate, n-butanol and water is 1:0.02:0.1:5;

[0077] (2) adjusting the pH value of the mixed solution to 4.0 with 3.0 mol / L sulfuric acid, stirring at 400 rpm for 7 h at 50° C., and subjecting the dispersion to 800 W output power high frequency radiation induced crystallization for 0.5 h to obtain a dispersion of modified mesoporous silica-based material;

[0078] (3) The dispersion was repeatedly washed with ethanol for 3 times;

[0079] (4) vacuum filtering the dispersion repeatedly washed with ethanol;

[0080] (5) Place the filtered sample in an oven and dry it at 70°C;

[0081] (6) The dried sample is crushed to obtain a powdery mesoporous purifier.

[0082] Comparative Example 1

[0083] A method for preparing a mesoporous purifier for the petroleum industry comprises the following steps:

[0084] Compared with Example 1, the difference of Comparative Example 1 is that in the step (2), the dispersion liquid is not subjected to 500 W output power high frequency radiation induced crystallization for 1 h, and other parameters and operations are the same as those of Example 1.

[0085] Test example, structure and performance detection and application effect of the high-efficiency mesoporous purifier of the present invention

[0086] The indicators of the high-efficiency mesoporous purifiers of Examples 1 to 4 and the mesoporous purifier of Comparative Example 1 were tested. The purifier was added to the recovered oil at a ratio of 3%, stirred for 30 minutes, and then centrifuged. The volatile organic content of the recovered oil was detected by a volatile organic detector; the specific surface area and pore size of the mesoporous purifier were detected by a static nitrogen adsorption method; the particle size of the mesoporous purifier was determined by a laser diffraction method; the results are shown in Table 1 below.

[0087] Table 1 Structure and performance test results of each mesoporous purifier

[0088]

[0089] Note: The smaller the VOC detection value, the stronger the adsorption capacity of the mesoporous purifier.

[0090] It can be seen from Table 1 above:

[0091] The high-efficiency mesoporous purifiers prepared in Examples 1 to 4 of the present invention have a specific surface area of ​​200 to 300 m by adjusting the raw material ratio and the microwave power range under the specific preparation process conditions provided by the present invention. 2 / g, the VOC detection value of the recycled oil after purification is 0-100ppm, and the pore size is 5-12nm. When the comparative example 1 is not subjected to microwave power crystallization, the VOC detection value of the recycled oil treated with the purifier is significantly improved, and at the same time, the specific surface area of ​​the material is reduced, and the pore size and particle size range are also expanded. Therefore, the VOC detection value of the mesoporous purifier of the present invention is low, the specific surface area is high, and it has good adsorption. At the same time, its pore size is large and the pore distribution is uniform, which can effectively absorb the odor substances in the oil and ensure the quality of the oil.

[0092] The present invention has been disclosed above with preferred embodiments, but those skilled in the art should understand that these embodiments are only used to describe the present invention and should not be understood as limiting the scope of the present invention. It should be noted that all changes and substitutions equivalent to these embodiments should be deemed to be included in the scope of the claims of the present invention. Therefore, the scope of protection of the present invention should be based on the scope defined in the claims.

Claims

1. A method for preparing a highly efficient mesoporous purifier, characterized in that: include: (1) dispersing a silicon source, a silane dispersant, and a crystal growth control agent in a solvent to form a mixed solution; (2) adding acid to adjust the pH, heating and stirring to obtain a dispersion; (3) after stopping stirring, subjecting the dispersion to a high-frequency radiation-induced crystallization treatment to obtain a dispersion of a modified mesoporous purifier; (4) Washing, filtering and drying the dispersion of the modified mesoporous purifier to obtain a high-efficiency mesoporous purifier.

2. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The mass ratio of the silicon source, the silane dispersant, the crystal growth controller and the solvent is 1:(0.01-1):(0.01-0.5):(4-25).

3. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The silicon source is one or more of ethyl orthosilicate, trichlorosilane, silicon tetrachloride, sodium silicate and methyltrimethylsilane.

4. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The silane dispersant is one or more of sodium hexametaphosphate, sodium chloride, sodium sulfate, sodium pyrophosphate, sodium dodecyl sulfonate and sodium dodecylbenzene sulfonate.

5. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The crystal growth controller is one or more of ethanol, isopropanol, glycerol, n-butanol, propylene oxide and dichloromethane.

6. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The solvent is one or more of water, acetic acid, ethanol, formic acid, acetone and glycerol.

7. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: Step (2) includes adjusting the pH value of the mixed solution to 2.0 to 7.0 using sulfuric acid with a concentration of 0.526 to 4.030 mol / L.

8. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The heating and stirring temperature is 30° C. to 60° C., the rotation speed is 100 to 500 rpm, and the stirring time is 3 to 8 hours.

9. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The output power of the high-frequency radiation-induced crystallization treatment is 200 to 800 W, and the crystallization time is 0.5 to 1 hour.

10. The method for preparing a high-efficiency mesoporous purifier according to claim 1, characterized in that: The washing includes one or more of water washing and alcohol washing; the filtration includes one or more of vacuum filtration, pressure filtration, centrifugal filtration and squeeze filtration; the drying includes one or more of oven drying, vacuum drying, freeze drying, supercritical CO2 drying and spray drying.

11. A highly efficient mesoporous purifier, characterized in that: The preparation method is described in any one of claims 1 to 10.

12. The high-efficiency mesoporous purifier according to claim 11, characterized in that: The specific surface area of ​​the high-efficiency mesoporous purifier is 200 to 300 m 2 / g, VOC detection value is 0-100ppm, and pore size is 5-12nm.

13. Use of the high-efficiency mesoporous purifier according to claim 11 or 12 in purifying recovered oil.

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