阅读说明：本技术 用于脱除有机溶剂微水的干凝胶及其制备方法和应用 (Xerogel for removing organic solvent micro-water and preparation method and application thereof ) 是由 王义明 李航 李莉 郭旭虹 于 2021-09-30 设计创作，主要内容包括：本发明公开了一种用于脱除有机溶剂微水的干凝胶,通过在普通干凝胶中加入具有吸湿性氯化物的聚吡咯而得到。本发明还公开了所述用于脱除有机溶剂微水的干凝胶的制备方法,以及所述干凝胶用于脱除有机溶剂微水的应用。本发明的干凝胶具有了能够更快的吸收储存有机溶剂中微量水的能力,解决了普通水凝胶难以脱除微量水的问题。与此同时,该干凝胶也能够被循环使用,在经过六次以上循环后仍然能达到很好的脱水效果,实现了能源的循环利用,减少能源消耗。(The invention discloses a dried gel for removing organic solvent micro-water, which is obtained by adding polypyrrole with hygroscopic chloride into common dried gel. The invention also discloses a preparation method of the xerogel for removing the organic solvent micro water and application of the xerogel for removing the organic solvent micro water. The xerogel of the invention has the capability of absorbing and storing trace water in organic solvent more quickly, and solves the problem that the trace water is difficult to remove by common hydrogel. Meanwhile, the xerogel can be recycled, and can still achieve good dehydration effect after more than six times of circulation, thereby realizing the recycling of energy and reducing the energy consumption.)

1. A dry gel for removing organic solvent trace water, which is obtained by adding polypyrrole having a hygroscopic chloride to a common dry gel.

2. A process for preparing a xerogel for the removal of organic solvent micro water as claimed in claim 1, characterized by comprising the steps of:

s1: alternately adding 0.5M ammonium persulfate solution and 1M pyrrole solution into 1.5M hydrochloric acid aqueous solution containing 1M lithium chloride, and continuously stirring, wherein the volume ratio of the ammonium persulfate solution to the pyrrole solution to the hydrochloric acid aqueous solution is 1:1: 5;

s2: polymerizing the mixed solution, washing and filtering the mixed solution by deionized water, and then uniformly dispersing the mixed solution in the deionized water by ultrasonic waves to obtain a polypyrrole hydrochloride solution;

s3: mixing a polymerization monomer, deionized water and N, N-methylene bisacrylamide according to a molar ratio of 50:5555:4 to form a mixed solution, adding an initiator and an accelerator after nitrogen is deoxidized for 1 hour to perform prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 500:10:1: 250;

s4: the hydrogel resulting from the polymerization was placed in an oven at 70 ℃ for 48 hours to obtain the xerogel.

3. The method according to claim 2, wherein the polymerizable monomer in S3 is a neutral monomer, a cationic monomer or an anionic monomer.

4. The method of claim 2, wherein the neutral monomer is selected from the group consisting of: n-isopropylacrylamide, acrylamide, hydroxyethyl methacrylate, and N-dimethylacrylamide.

5. The method of claim 2, wherein the cationic monomer is selected from the group consisting of: dimethylaminopropylacrylamide, [ (2-methacryloyloxy) ethyl ] trimethylammonium chloride, (2-dimethylamino) ethyl methacrylate, 2-aminoethyl methacrylate hydrochloride, (3-acrylamidopropyl) trimethylammonium chloride, 2- (dimethylamino) ethyl acrylate, N- [3- (dimethylamino) propyl ] methacrylamide, N- [3- (dimethylamino) propyl ] acrylamide, [2- (acryloyloxy) ethyl ] trimethylammonium chloride, [3- (methacrylamido) propyl ] trimethylammonium chloride, and (vinylbenzyl) trimethylammonium chloride.

6. The method of claim 2, wherein the anionic monomer is selected from the group consisting of: acrylic acid, acrylamidopropanesulfonic acid esters, 2-acrylamido-2-methylpropanesulfonic acid, vinyl alcohol, and maleic anhydride.

7. The method according to claim 2, wherein the concentration of the polypyrrole hydrochloride solution in S3 is 5 g/l to 15 g/l.

8. Use of the xerogel of claim 1 for the removal of trace water from organic solvents, wherein the organic solvent is a finished oil product, including crude oil, jet fuel, and gasoline.

9. A method for removing trace water from an organic solvent, which comprises charging the xerogel of claim 1 into the organic solvent.

10. The use according to claim 9, wherein the organic solvent is a finished petroleum product, including crude oil, jet fuel, and gasoline.

Technical Field

The invention belongs to the field of chemical engineering and technology, and is especially dry gel for eliminating organic solvent and its preparation process and application.

Background

In chemical production, a lot of organic solvents are inevitably mixed with trace moisture, which not only affects the properties of the organic solvents, but also corrodes and damages the transportation and storage equipment of the organic solvents, resulting in safety accidents and huge economic losses. In addition, in some specific application occasions, the organic solvent also puts special requirements on the water content of the organic solvent, for example, the water content of oil products such as aviation kerosene, gasoline and the like is always strictly controlled, otherwise, the faults of a conveying pipeline and an engine are caused, and serious results are generated. For another example, in the refining process of petroleum, when water and crude oil are heated together, the water is rapidly vaporized and expanded, the pressure is increased, the normal operation and the product quality of a refinery are affected, and even explosion can occur. In view of this, the removal of the trace water in the organic solvent is an important production process in industrial production, however, the trace water is often present in a form that is miscible with the organic solvent, so that the removal is very difficult. The common micro-water removal method generally adopts an electric dehydration method, which has high efficiency, but has high energy consumption and high economic cost. Therefore, the development of a simple and efficient organic solvent micro-water removal method is urgent.

Hydrogel is a rapidly developing polymer material, is soft in nature, and can maintain a certain shape. The three-dimensional network structure is formed by mutual crosslinking through covalent bonds, hydrogen bonds or van der Waals force and the like, can hold water which is several times or even hundreds times of the weight of the three-dimensional network structure, and can integrate water absorption, water retention and slow release into a whole. As a material with high water absorption and high water retention, hydrogel is widely used for dehydration of petroleum organic solvents and the like. Although the use of xerogels for the dehydration of organic solvents has been common, the dehydration is less than ideal due to the limited ability of conventional xerogels to capture free water molecules.

Polypyrrole materials have strong hygroscopicity and the ability of capturing micro water in air, and polypyrrole has been studied to be applied to collection of moisture in the atmosphere and to soil water retention. However, no reports of the use of dry gels containing polypyrrole for removing traces of water in organic solvents have been found in the prior art.

Disclosure of Invention

In order to overcome the problem that the common hydrogel can not capture trace water molecules, the invention provides the dry gel containing polypyrrole, which can more quickly absorb and store the trace water in the organic solvent, thereby solving the problem that the common hydrogel is difficult to remove the trace water.

In order to achieve the above objects, in a first aspect of the present invention, there is provided a xerogel for removing organic solvent trace water, which is obtained by adding polypyrrole having a hygroscopic chloride to a conventional xerogel.

In a second aspect of the present invention, there is provided a process for preparing the xerogel for removing organic solvent micro-water, comprising the steps of:

s1: alternately adding 0.5M ammonium persulfate solution and 1M pyrrole solution into 1.5M hydrochloric acid aqueous solution containing 1M lithium chloride, and continuously stirring, wherein the volume ratio of the ammonium persulfate solution to the pyrrole solution to the hydrochloric acid aqueous solution is 1:1: 5;

s2: polymerizing the mixed solution, washing and filtering the mixed solution by deionized water, and then uniformly dispersing the mixed solution in the deionized water by ultrasonic waves to obtain a polypyrrole hydrochloride solution;

s3: mixing a polymerization monomer, deionized water and N, N-methylene bisacrylamide according to a molar ratio of 50:5555:4 to form a mixed solution, adding an initiator and an accelerator after nitrogen is deoxidized for 1 hour to perform prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 500:10:1: 250;

s4: and (3) putting the hydrogel generated by polymerization into an oven for drying to obtain the xerogel.

According to the present invention, the polymerized monomer described in S3 is a neutral monomer, a cationic monomer or an anionic monomer, wherein:

the neutral monomer is selected from: n-isopropylacrylamide, acrylamide, hydroxyethyl methacrylate, and N-dimethylacrylamide.

The cationic monomer is selected from: dimethylaminopropylacrylamide, [ (2-methacryloyloxy) ethyl ] trimethylammonium chloride, (2-dimethylamino) ethyl methacrylate, 2-aminoethyl methacrylate hydrochloride, (3-acrylamidopropyl) trimethylammonium chloride, 2- (dimethylamino) ethyl acrylate, N- [3- (dimethylamino) propyl ] methacrylamide, N- [3- (dimethylamino) propyl ] acrylamide, [2- (acryloyloxy) ethyl ] trimethylammonium chloride, [3- (methacrylamido) propyl ] trimethylammonium chloride, and (vinylbenzyl) trimethylammonium chloride.

The anionic monomer is selected from: acrylic acid, acrylamidopropanesulfonic acid esters, 2-acrylamido-2-methylpropanesulfonic acid, vinyl alcohol, and maleic anhydride.

According to the invention, the concentration of the polypyrrole hcl solution in S3 is between 5 g/l and 15 g/l.

In a third aspect of the invention, the application of the xerogel in removing micro water in an organic solvent is provided, wherein the organic solvent is a finished oil product, including crude oil, aviation kerosene and gasoline.

In a fourth aspect of the present invention, there is provided a method for removing trace water from an organic solvent, comprising charging the above-mentioned xerogel into the organic solvent.

Further, the organic solvent is a finished product oil product, including crude oil, aviation kerosene and gasoline.

The invention has the following beneficial effects:

1. the dried gel for removing the organic solvent micro-water greatly enhances the water molecule absorbing capacity of the hydrogel by adding the polypyrrole with hygroscopic chloride in the hydrogel, so that the dried gel can absorb more water more quickly in an environment with lower water content, and the removal of the micro-water in crude oil and various product oils is achieved.

2. The xerogel can quickly capture micro water molecules in the organic solvent and can remove the water content in the organic solvent to be below 10 micrograms/milliliter.

3. The xerogel can be recycled, can still achieve good dehydration effect after more than six cycles, and has wide application prospect.

4. The xerogel has low price and wide source, is more economical and practical compared with the common electric dehydration method, and effectively solves the problem that the hydrogel is difficult to be used for removing organic solvent, especially trace water in the oil product of the finished oil.

Drawings

FIG. 1 is a schematic diagram of the removal of trace water from an organic solvent by a xerogel of the present invention.

Figure 2 is a photograph of the hydrogel before oven drying.

Fig. 3 is a photograph of the oven dried xerogel.

FIG. 4 is a schematic representation of the effect of the xerogels of examples 2-5 in removing trace water from aviation kerosene.

FIG. 5 is a graph showing the effect of the xerogels of examples 7-10 in removing trace water from aviation kerosene.

Fig. 6 is a schematic representation of the effect of the xerogel of example 3 for the recycling removal of micro-water in aviation kerosene.

Fig. 7 is a schematic representation of the effect of the xerogel of example 8 on the recycling removal of micro-water from aviation kerosene.

Detailed Description

The technical solution of the present invention is clearly and completely described in the following embodiments with reference to the accompanying drawings. It is to be understood that the described embodiments are only a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the invention without making creative efforts, fall within the scope of the invention.

The principle of removing the micro water from the organic solvent by the xerogel of the invention is shown in figure 1. The trace amount of water dissolved in the organic solvent is captured by the xerogel by two steps: 1) the trace amount of water dissolved in the organic solvent is concentrated in the gel due to the hygroscopicity of polypyrrole hydrochloride; 2) the enriched water molecules in polypyrrole hydrochloride are captured by the hydrophilic polymer network for storage, with the consequent expansion of the gel.

Example 1: preparation of a solution of polypyrrole hydrochloride

S1: alternately adding 0.5M ammonium persulfate solution and 1M pyrrole solution into 1.5M hydrochloric acid aqueous solution containing 1M lithium chloride, and continuously stirring, wherein the volume ratio of the three solutions is 1:1: 5;

s2: and after polymerizing for 15-30 minutes, washing and filtering by deionized water, and then uniformly dispersing in the deionized water by ultrasonic to obtain polypyrrole hydrochloride solution for later use.

Example 2: preparation of dry gel containing polypyrrole hydrochloride

S1: taking the polypyrrole hydrochloride solution obtained in the example 1, and adjusting the concentration to be 5 g/L by using deionized water;

s2: mixing neutral polymerization monomers of N-isopropylacrylamide, deionized water and N, N-methylene bisacrylamide according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator 0.5M ammonium persulfate solution and an accelerator tetramethyl ethylenediamine, carrying out prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 1000:20:2: 500;

s3: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel containing polypyrrole hydrochloride.

Fig. 2 shows a photograph of the hydrogel before oven drying and fig. 3 shows a photograph of the xerogel after oven drying, showing that the hydrogel has a greatly reduced volume after drying, and that the xerogel can store a large amount of water from a comparison of the change in volume of the xerogel.

Example 3: preparation of dry gel containing polypyrrole hydrochloride

S1: taking the polypyrrole hydrochloride solution obtained in the example 1, and adjusting the concentration to be 10 g/L by using deionized water;

s2: mixing neutral polymerization monomers of N-isopropylacrylamide, deionized water and N, N-methylene bisacrylamide according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator 0.5M ammonium persulfate solution and an accelerator tetramethyl ethylenediamine, carrying out prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 1000:20:2: 500;

s3: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel containing polypyrrole hydrochloride.

Example 4: preparation of dry gel containing polypyrrole hydrochloride

S1: taking the polypyrrole hydrochloride solution obtained in the example 1, and adjusting the concentration to be 15 g/L by using deionized water;

s2: mixing neutral polymerization monomers of N-isopropylacrylamide, deionized water and N, N-methylene bisacrylamide according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator 0.5M ammonium persulfate solution and an accelerator tetramethyl ethylenediamine, carrying out prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 1000:20:2: 500;

s3: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel containing polypyrrole hydrochloride.

Example 5: preparation of a dry gel free of polypyrrole hydrochloride

S1: mixing neutral polymerization monomers of N-isopropylacrylamide, deionized water and N, N-methylene bisacrylamide according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator of 0.5M ammonium persulfate solution and an accelerator of tetramethylethylenediamine, carrying out prepolymerization, and then adding deionized water, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the deionized water is 1000:20:2: 500;

s2: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel without polypyrrole hydrochloride.

Example 6: water absorption effect test of xerogel in aviation kerosene

10 ml of aviation kerosene was taken, the initial water content thereof was measured, and then 0.1 g each of the xerogels synthesized in examples 2, 3, 4 and 5 was put into 10 ml of aviation kerosene and stored in a sealed state, and the water content in the aviation kerosene was measured every 2 hours by a micro-moisture meter.

The test results are shown in fig. 4. From the results of FIG. 4, it can be seen that the poly (isopropylacrylamide) xerogel containing polypyrrole hydrochloride of the present invention (examples 2 to 4) has a greater gain in water absorption rate in aviation kerosene and in the effect of eventually being able to dehydrate than the conventional poly (isopropylacrylamide) xerogel (example 5).

Example 7: preparation of dry gel containing polypyrrole hydrochloride

S1: taking the polypyrrole hydrochloride solution obtained in the example 1, and adjusting the concentration to be 5 g/L by using deionized water;

s2: mixing cationic polymerization monomers, namely dimethylamino propyl acrylamide, deionized water and N, N-methylene bisacrylamide, according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator 0.5M ammonium persulfate solution and an accelerator, namely tetramethyl ethylene diamine, carrying out prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 1000:20:2: 500;

s3: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel containing polypyrrole hydrochloride.

Example 8: preparation of dry gel containing polypyrrole hydrochloride

S1: taking the polypyrrole hydrochloride solution obtained in the example 1, and adjusting the concentration to be 10 g/L by using deionized water;

s2: mixing cationic polymerization monomers, namely dimethylamino propyl acrylamide, deionized water and N, N-methylene bisacrylamide, according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator 0.5M ammonium persulfate solution and an accelerator, namely tetramethyl ethylene diamine, carrying out prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 1000:20:2: 500;

s3: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel containing polypyrrole hydrochloride.

Example 9: preparation of dry gel containing polypyrrole hydrochloride

S1: taking the polypyrrole hydrochloride solution obtained in the example 1, and adjusting the concentration to be 15 g/L by using deionized water;

s2: mixing cationic polymerization monomers, namely dimethylamino propyl acrylamide, deionized water and N, N-methylene bisacrylamide, according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator 0.5M ammonium persulfate solution and an accelerator, namely tetramethyl ethylene diamine, carrying out prepolymerization, and then adding a polypyrrole hydrochloride solution, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the polypyrrole hydrochloride solution is 1000:20:2: 500;

s3: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel containing polypyrrole hydrochloride.

Example 10: preparation of a dry gel free of polypyrrole hydrochloride

S1: mixing cationic polymerization monomers, namely dimethylamino propyl acrylamide, deionized water and N, N-methylene bisacrylamide, according to a molar ratio of 50:5555:4 to form a mixed solution, removing oxygen by using nitrogen for 1 hour, adding an initiator 0.5M ammonium persulfate solution and an accelerator, namely tetramethyl ethylenediamine, carrying out prepolymerization, and then adding deionized water, wherein the volume ratio of the mixed solution to the initiator, the accelerator and the deionized water is 1000:20:2: 500;

s2: the hydrogel produced by polymerization is put into an oven at 70 ℃ for drying for more than 48 hours to obtain dry gel without polypyrrole hydrochloride.

Example 11: water absorption effect test of xerogel in aviation kerosene

10 ml of aviation kerosene was taken, the initial water content thereof was measured, and then 0.1 g each of the xerogels synthesized in examples 7, 8, 9 and 10 was put into 10 ml of aviation kerosene and stored in a sealed state, and the water content in the aviation kerosene was measured every 2 hours by a micro-moisture meter.

The test results are shown in fig. 5. From the results shown in FIG. 5, it can be seen that the poly (dimethylaminopropyl acrylamide) xerogel containing polypyrrole hydrochloride provided by the present invention (examples 7-9) has a greater gain in water absorption rate in aviation kerosene and the effect of being able to be dehydrated finally compared with the common poly (dimethylaminopropyl acrylamide) xerogel (example 10).

Example 12: effect of dry gel containing polypyrrole hydrochloride on micro-water circulation removal in aviation kerosene

10 ml of aviation kerosene were taken and tested for initial water content, after which 0.1 g of the xerogel synthesized according to example 3 was introduced into it and stored in a sealed manner for 24 hours, with the water content being measured every 2 hours during the first 6 hours. After one cycle, the xerogel was taken out and put into new 10 ml aviation kerosene, and the experiment was repeated.

The test results are shown in fig. 6. The results in fig. 6 show that the poly-isopropyl acrylamide xerogel provided by the invention can still achieve good dehydration effect after more than six cycles in aviation kerosene, and has good recycling property.

Example 13: effect of dry gel containing polypyrrole hydrochloride on micro-water circulation removal in aviation kerosene

10 ml of aviation kerosene was taken and tested for initial water content, after which 0.1 g of the xerogel synthesized according to example 8 was introduced into it and stored in a sealed manner for 24 hours, with the water content being measured every 2 hours during the first 6 hours. After one cycle, the xerogel was taken out and put into new 10 ml aviation kerosene, and the experiment was repeated.

The test results are shown in fig. 7. The results in fig. 7 show that the polydimethylaminopropyl acrylamide xerogel provided by the invention can still achieve good dehydration effect after more than six times of circulation in aviation kerosene, and has good recycling property.