Crosslinked composite desulfurizer and its preparation method

Abstract

The present invention relates to the technical field of desulfurizing agents, and is a crosslinked composite desulfurizing agent and its preparation method, which is carried out according to the following steps: Mix the required amount of alkanolamine and aldehyde for reaction to obtain an aqueous solution of monocyclic triazine. After dehydrating and purifying the aqueous solution of monocyclic triazine, sequentially add the required amount of dicarboxylic acid, higher fatty acid, catalyst and xylene to a part of the required amount of the purified aqueous solution of monocyclic triazine, and react to obtain a crosslinked and oil-soluble desulfurizing agent. Then, add the crosslinked and oil-soluble desulfurizing agent and emulsifier to another part of the required amount of the purified aqueous solution of monocyclic triazine, and stir evenly to obtain a crosslinked composite desulfurizing agent. The crosslinked composite desulfurizing agent obtained by the present invention realizes polycyclic azide. On the one hand, it can effectively remove hydrogen sulfide in oil and further reduce the sulfur content in the oil-water produced fluid, having high desulfurization ability. On the other hand, it also reduces the dosage of the desulfurizing agent and reduces the desulfurization cost of oil and gas field sewage.

Description

Technical Field

[0001] The present invention relates to the technical field of desulfurizing agents, and is a cross-linked composite desulfurizing agent and a preparation method thereof. Background Art

[0002] The transportation of sulfur-containing sewage in natural gas gas fields is characterized by large volume, long distance, and relatively high risks. Gas field sewage is generally purified and reinjected through equipment such as filters, pressure pumps, and injection pumps. In these processes, pipeline and equipment corrosion often occurs, seriously affecting normal production and causing huge economic losses. In some areas, centralized transportation methods are adopted to solve this problem. However, once leakage occurs during transportation, combined with substances such as dissolved hydrogen sulfide in the water, it may lead to malignant environmental protection accidents such as pollution of drinking water source intake points and even accident risks of poisoning of surrounding personnel. Hydrogen sulfide is a highly irritating gas with a strong rotten egg smell. The presence of hydrogen sulfide during the production process of oil and gas wells not only causes equipment and pipeline corrosion and catalyst poisoning, but also seriously threatens personal safety.

[0003] Chinese patent document with publication number CN117164530A discloses a polycyclic azide desulfurizing agent and a synthesis method thereof, including the following steps: mixing and stirring an alcoholamine and an amide evenly and heating, dropping a catalyst, and obtaining a monocyclic triazine after the reaction; heating the obtained monocyclic azide compound, adding a polyaldehyde, mixing and stirring evenly, dropping a catalyst, and stirring to achieve a coupling reaction; or mixing and stirring a small molecule aldehyde and an amide evenly and heating, dropping a catalyst, adding an amide after the reaction, dropping a catalyst, and stirring to achieve a coupling reaction; separating by-products from the obtained product after the coupling reaction and purifying. The poly-triazine ring of this desulfurizing agent can achieve a high monomer desulfurization rate, effectively reduce the sulfur content in sewage, and the generated product is soluble in water and will not affect normal production.

[0004] It can be seen that triazine-based desulfurizing agents have the advantages of good desulfurization efficiency, being easily prepared industrially, the product being soluble in water, low toxicity, having bactericidal properties, being able to reduce equipment corrosion, being environmentally friendly, having low requirements for equipment during industrial use, being easy to operate, and having low costs. However, in the on-site implementation process, usually only a single water-soluble desulfurizing agent is mainly used. Although this method can effectively reduce the sulfur content in water, since the desulfurizing agent cannot enter the oil phase, the treatment effect is slow, and the hydrogen sulfide content in the treated crude oil is relatively high. Summary of the Invention

[0005] The present invention provides a cross-linked composite desulfurizing agent and a preparation method thereof, which overcome the above-mentioned deficiencies of the prior art and can effectively solve the problems that the existing desulfurizing agent cannot enter the oil phase, resulting in slow desulfurization effect and low desulfurization ability, thus leading to a large amount of desulfurizing agent used and high desulfurization cost.

[0006] One of the technical solutions of the present invention is achieved by the following measures: A preparation method of a cross-linked composite desulfurizer is carried out according to the following steps:

[0007] S1, Mix the required amount of alkanolamine and aldehyde for reaction to obtain an aqueous solution of monocyclic triazine;

[0008] S2, After dehydrating and purifying the aqueous solution of monocyclic triazine, add the required amount of dibasic carboxylic acid, higher fatty acid, catalyst and xylene to a part of the required amount of the purified aqueous solution of monocyclic triazine in sequence, and react to obtain a cross-linked and oil-soluble desulfurizer;

[0009] S3, Then add the cross-linked and oil-soluble desulfurizer and emulsifier to another part of the required amount of the purified aqueous solution of monocyclic triazine, and stir evenly to obtain a cross-linked composite desulfurizer.

[0010] The following is a further optimization or / and improvement of one of the above-mentioned invention technical solutions:

[0011] In the above step S1, the molar ratio of alkanolamine to aldehyde is 1:1.

[0012] In the above step S1, the alkanolamine is monoethanolamine and the aldehyde is formaldehyde.

[0013] In the above step S1, the reaction temperature is 60 °C and the reaction time is 3.0 h.

[0014] In the above step S2, the molar ratio of the carboxylic acid group in the dibasic carboxylic acid to the added purified aqueous solution of monocyclic triazine is 1:1 to 2, the molar ratio of the higher fatty acid to the added purified aqueous solution of monocyclic triazine is 1:1 to 2, and the addition amount of the catalyst is 0.4% to 2.5% of the mass of the added purified aqueous solution of monocyclic triazine.

[0015] In the above step S2, the dibasic carboxylic acid is one of adipic acid and glutaric acid, the higher fatty acid is one or more of lauric acid, myristic acid, palmitic acid, and stearic acid, and the catalyst is one or more of dodecylbenzenesulfonic acid, p-toluenesulfonic acid, and sulfamic acid.

[0016] In the above step S2, the reaction temperature is 120 °C to 150 °C and the reaction time is 2.0 h to 10.0 h.

[0017] In the above step S3, the mass ratio of the added purified aqueous solution of monocyclic triazine to the cross-linked and oil-soluble desulfurizer is 1:0.2 to 1.0.

[0018] In the above step S3, the emulsifier is one or more of sodium dodecyl sulfate, diethylene glycol monostearate, fatty alcohol polyoxyethylene ether, polyethylene glycol dilaurate, and polyglycerol ricinoleate. Among them, the addition amount of the emulsifier is 1% to 15% of the mass of the aqueous solution of monocyclic triazine.

[0019] The second technical solution of the present invention is achieved by the following measures: a cross-linked composite desulfurizer prepared by a preparation method of a cross-linked composite desulfurizer.

[0020] The cross-linked composite desulfurizer obtained in the present invention realizes polycyclic azide. On the one hand, it can effectively remove hydrogen sulfide in oil and further reduce the sulfur content in the produced oil and water, having high desulfurization ability. On the other hand, it also reduces the dosage of the desulfurizer and reduces the desulfurization cost of oil and gas field sewage. Specific embodiments

[0021] The present invention is not limited by the following embodiments, and the specific implementation manners can be determined according to the technical solution of the present invention and the actual situation. All kinds of chemical reagents and chemical supplies mentioned in the present invention are well-known and commonly used chemical reagents and chemical supplies in the prior art without special instructions; the percentages in the present invention are mass percentages without special instructions; the solutions in the present invention are aqueous solutions with water as the solvent without special instructions. For example, a hydrochloric acid solution is an aqueous solution of hydrochloric acid; normal temperature and room temperature in the present invention generally refer to a temperature range of 15°C to 25°C, and are generally defined as 25°C.

[0022] The present invention will be further described below in conjunction with embodiments:

[0023] Example 1: The preparation method of the cross-linked composite desulfurizer is carried out according to the following steps:

[0024] S1, Mix the required amount of alkanolamine and aldehyde for reaction to obtain a monocyclic triazine aqueous solution;

[0025] S2, After dehydrating and purifying the monocyclic triazine aqueous solution, add the required amount of dicarboxylic acid, higher fatty acid, catalyst and xylene to a part of the purified monocyclic triazine aqueous solution in sequence, and react to obtain a cross-linked and oil-soluble desulfurizer;

[0026] S3, Then add the cross-linked and oil-soluble desulfurizer and emulsifier to another part of the required amount of purified monocyclic triazine aqueous solution, and stir evenly to obtain a cross-linked composite desulfurizer.

[0027] Example 2: As an optimization of the above embodiment, in step S1, the molar ratio of alkanolamine to aldehyde is 1:1.

[0028] Example 3: As an optimization of the above embodiment, in step S1, the alkanolamine is monoethanolamine and the aldehyde is formaldehyde.

[0029] Example 4: As an optimization of the above embodiment, in step S1, the reaction temperature is 60°C and the reaction time is 3.0 h.

[0030] Example 5: As an optimization of the above example, in step S2, the molar ratio of the carboxylic acid groups in the dicarboxylic acid to the purified aqueous solution of monocyclic triazine added is 1:1 to 2, the molar ratio of the higher carboxylic acid to the purified aqueous solution of monocyclic triazine added is 1:1 to 2, and the addition amount of the catalyst is 0.4% to 2.5% of the mass of the purified aqueous solution of monocyclic triazine added.

[0031] Example 6: As an optimization of the above example, in step S2, the dicarboxylic acid is one of adipic acid and glutaric acid, the higher carboxylic acid is one or more of dodecanoic acid, tetradecanoic acid, hexadecanoic acid, and octadecanoic acid, and the catalyst is one or more of dodecylbenzenesulfonic acid, p-toluenesulfonic acid, and sulfamic acid.

[0032] Example 7: As an optimization of the above example, in step S2, the reaction temperature is 120°C to 150°C, and the reaction time is 2.0 h to 10.0 h.

[0033] Example 8: As an optimization of the above example, in step S3, the mass ratio of the purified aqueous solution of monocyclic triazine added to the crosslinked and oil-soluble desulfurizer is 1:0.2 to 1.0.

[0034] Example 9: As an optimization of the above example, in step S3, the emulsifier is one or more of sodium dodecyl sulfate, diethylene glycol monostearate, fatty alcohol polyoxyethylene ether, polyethylene glycol dilaurate, and polyglycerol ricinoleate. Among them, the addition amount of the emulsifier is 1% to 15% of the mass of the aqueous solution of monocyclic triazine.

[0035] Example 10: The crosslinked composite desulfurizer prepared by the preparation method of the crosslinked composite desulfurizer.

[0036] Example 11: The crosslinked composite desulfurizer is prepared according to the following steps:

[0037] S1, Add all 1830 kg of monoethanolamine to the kettle, turn on the stirring device and adjust the rotation speed to 100 rpm, turn on the heating device, control the temperature at 60°C, open the constant-pressure dropping funnel containing formaldehyde, slowly adjust the dropping speed of formaldehyde, and add a total of 2500 kg of formaldehyde. React at 60°C for 3 h to obtain an aqueous solution of monocyclic triazine;

[0038] S2, Take 1210 kg of the purified aqueous solution of monocyclic triazine, add 80 kg of adipic acid, 5 kg of sulfamic acid, and 200 kg of octadecanoic acid, add 1200 kg of xylene (solvent), control the temperature at 140°C and react for 6 h to obtain a crosslinked and oil-soluble desulfurizer;

[0039] S3. Take 500 kg of the purified aqueous solution of monocyclic triazine, add 10 kg of sodium dodecyl sulfate, 2 kg of diethylene glycol monostearate, and 500 kg of crosslinked and oil-soluble desulfurizer. After stirring evenly, a crosslinked composite desulfurizer is obtained.

[0040] Example 12: The crosslinked composite desulfurizer is prepared according to the following steps:

[0041] S1. Add all 1830 kg of monoethanolamine into the kettle, start the stirring device and adjust the rotation speed to 100 rpm. Start the heating device, control the temperature at 60 °C, open the constant-pressure dropping funnel containing formaldehyde, and slowly adjust the dropping rate of formaldehyde. A total of 2500 kg of formaldehyde is added, and the reaction is carried out at 60 °C for 3 h to obtain an aqueous solution of monocyclic triazine.

[0042] S2. Take 1210 kg of the purified aqueous solution of monocyclic triazine, add 80 kg of glutaric acid, 5 kg of aminosulfonic acid, 200 kg of stearic acid, and add 1200 kg of xylene (solvent). Control the temperature at 150 °C and react for 2 h to obtain a crosslinked and oil-soluble desulfurizer.

[0043] S3. Take 500 kg of the purified aqueous solution of monocyclic triazine, add 10 kg of sodium dodecyl sulfate, 2 kg of diethylene glycol monostearate, and 500 kg of crosslinked and oil-soluble desulfurizer. After stirring evenly, a crosslinked composite desulfurizer is obtained.

[0044] Example 13: The crosslinked composite desulfurizer is prepared according to the following steps:

[0045] S1. Add all 1830 kg of monoethanolamine into the kettle, start the stirring device and adjust the rotation speed to 100 rpm. Start the heating device, control the temperature at 60 °C, open the constant-pressure dropping funnel containing formaldehyde, and slowly adjust the dropping rate of formaldehyde. A total of 2500 kg of formaldehyde is added, and the reaction is carried out at 60 °C for 3 h to obtain an aqueous solution of monocyclic triazine.

[0046] S2. Take 1210 kg of the purified aqueous solution of monocyclic triazine, add 80 kg of adipic acid, 5 kg of p-toluenesulfonic acid, 200 kg of stearic acid, and add 1200 kg of xylene (solvent). Control the temperature at 120 °C and react for 10 h to obtain a crosslinked and oil-soluble desulfurizer.

[0047] S3. Take 500 kg of the purified aqueous solution of monocyclic triazine, add 10 kg of sodium dodecyl sulfate, 2 kg of fatty alcohol polyoxyethylene ether, and 500 kg of crosslinked and oil-soluble desulfurizer. After stirring evenly, a crosslinked composite desulfurizer is obtained.

[0048] Example 14: The crosslinked composite desulfurizer is prepared according to the following steps:

[0049] S1. Add all 1830 kg of monoethanolamine into the reactor. Start the stirring device and adjust the rotation speed to 600 rpm. Start the heating device, control the temperature at 60 °C. Open the constant-pressure dropping funnel containing formaldehyde, slowly adjust the dropping rate of formaldehyde, and add a total of 2500 kg of formaldehyde. React for 3 h at 60 °C to obtain an aqueous solution of monocyclic triazine.

[0050] S2. Take 1210 kg of the purified aqueous solution of monocyclic triazine, add 80 kg of adipic acid, 5 kg of aminosulfonic acid, 200 kg of hexadecanoic acid, and 1200 kg of xylene (solvent). Control the temperature at 130 °C and react for 8 h to obtain a crosslinked and oil-soluble desulfurizer.

[0051] S3. Take 500 kg of the purified aqueous solution of monocyclic triazine, add 10 kg of sodium dodecyl sulfate, 2 kg of diethylene glycol monostearate, and 500 kg of the crosslinked and oil-soluble desulfurizer. Stir evenly to obtain a crosslinked composite desulfurizer.

[0052] Example 15: The crosslinked composite desulfurizer is prepared according to the following steps:

[0053] S1. Add all 1830 kg of monoethanolamine into the reactor. Start the stirring device and adjust the rotation speed to 600 rpm. Start the heating device, control the temperature at 60 °C. Open the constant-pressure dropping funnel containing formaldehyde, slowly adjust the dropping rate of formaldehyde, and add a total of 2500 kg of formaldehyde. React for 3 h at 60 °C to obtain an aqueous solution of monocyclic triazine.

[0054] S2. Take 1210 kg of the purified aqueous solution of monocyclic triazine, add 80 kg of adipic acid, 5 kg of aminosulfonic acid, 200 kg of dodecanoic acid, and 1200 kg of xylene (solvent). Control the temperature at 140 °C and react for 6 h to obtain a crosslinked and oil-soluble desulfurizer.

[0055] S3. Take 500 kg of the purified aqueous solution of monocyclic triazine, add 10 kg of sodium dodecyl sulfate, 2 kg of diethylene glycol monostearate, and 500 kg of the crosslinked and oil-soluble desulfurizer. Stir evenly to obtain a crosslinked composite desulfurizer.

[0056] Example 16: The crosslinked composite desulfurizer is prepared according to the following steps:

[0057] S1. Add all 1830 kg of monoethanolamine into the reactor. Start the stirring device and adjust the rotation speed to 600 rpm. Start the heating device, control the temperature at 60 °C. Open the constant-pressure dropping funnel containing formaldehyde, slowly adjust the dropping rate of formaldehyde, and add a total of 2500 kg of formaldehyde. React for 3 h at 60 °C to obtain an aqueous solution of monocyclic triazine.

[0058] S2. Take 1210 kg of the purified aqueous solution of monocyclic triazine, add 80 kg of adipic acid, 5 kg of aminosulfonic acid, and 200 kg of stearic acid. Then add 1200 kg of xylene (solvent), control the temperature at 140 °C and react for 6 h to obtain a cross-linked and oil-soluble desulfurizer.

[0059] S3. Take 500 kg of the purified aqueous solution of monocyclic triazine, add 10 kg of sodium dodecyl sulfate, 2 kg of diglycol dilaurate, and 500 kg of the cross-linked and oil-soluble desulfurizer. After stirring evenly, a cross-linked composite desulfurizer is obtained.

[0060] Comparative Example 1: Use the aqueous solution of monocyclic triazine obtained in step S1 of Example 11 as the desulfurizer.

[0061] Comparative Example 2: Use the cross-linked and oil-soluble desulfurizer obtained in step S2 of Example 11 as the desulfurizer.

[0062] Perform performance tests on the cross-linked composite desulfurizers obtained in Examples 11 to 16.

[0063] Take the oil-water produced fluid from the oilfield site and conduct an oil removal performance evaluation experiment on the cross-linked composite desulfurizers obtained in Examples 11 to 16 and the desulfurizers obtained in Comparative Examples 1 and 2. Respectively investigate the influence of the agents on the desulfurization performance at the same dosing concentration. The specific evaluation method is as follows:

[0064] Take 1 L of the oil-water mixed sample from the site, put it into a closed container, then heat it to 60 °C, and test the content of hydrogen sulfide in the gas phase. The results are shown in Table 1.

[0065] Respectively take 1 L of the oil-water mixed sample from the site, add 500 ppm of each of the cross-linked composite desulfurizers obtained in Examples 11 to 16, put it into a closed container, then heat it to 60 °C, and test the content of hydrogen sulfide in the gas phase. The results are shown in Table 1.

[0066] Respectively take 1 L of the oil-water mixed sample from the site, add 500 ppm of each of the desulfurizers obtained in Comparative Examples 1 and 2, put it into a closed container, then heat it to 60 °C, and test the content of hydrogen sulfide in the gas phase. The results are shown in Table 1.

[0067] Table 1

[0068] 。

[0069] As can be seen from Table 1, by comparing Example 11 with Examples 12, 13, and 16, it can be known that different catalysts, cross-linking agents, and emulsifiers have little influence on the performance of the product formula.

[0070] From the comparison of Example 11, Example 14, and Example 15, it can be seen that different carbon chain lengths of the added higher fatty acids have a certain impact on the performance of the desulfurizer. Mainly when the carbon chain is relatively short, it affects the dissolution and diffusion of the oil-soluble desulfurizer in the oil. It can be seen that the cross-linked and oil-soluble desulfurizer with 18 carbon atoms in the added higher fatty acid has the best effect.

[0071] It can be seen from this that for the oil-water mixture, using a single oil-soluble desulfurizer (Comparative Example 2) and a single water-soluble desulfurizer (Comparative Example 1) both have relatively poor effects. Using the cross-linked composite desulfurizer of the present invention can effectively remove sulfides in the liquid phase.

[0072] In summary, the cross-linked composite desulfurizer obtained by the present invention realizes polycyclic azide. On the one hand, it can effectively remove hydrogen sulfide in the oil and further reduce the sulfur content in the oil-water produced fluid, having high desulfurization ability. On the other hand, it also reduces the dosage of the desulfurizer and reduces the desulfurization cost of oil and gas field sewage.

[0073] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effects. Non-essential technical features can be added or subtracted according to actual needs to meet the requirements of different situations.

Claims

1. A preparation method of a cross-linked composite desulfurizer, characterized in that Proceed as follows: S1. Mix the required amount of alkanolamine and aldehyde for reaction to obtain an aqueous solution of monocyclic triazine, where the molar ratio of alkanolamine to aldehyde is 1:1, the reaction temperature is 60 °C, and the reaction time is 3.0 h; S2. After dehydrating and purifying the aqueous solution of monocyclic triazine, add the required amount of dicarboxylic acid, higher fatty acid, catalyst, and xylene to a part of the required amount of the purified aqueous solution of monocyclic triazine in sequence and react to obtain a cross-linked and oil-soluble desulfurizer, where the molar ratio of the carboxylic acid group in the dicarboxylic acid to the added purified aqueous solution of monocyclic triazine is 1:1 to 2, the molar ratio of the higher fatty acid to the added purified aqueous solution of monocyclic triazine is 1:1 to 2, the addition amount of the catalyst is 0.4% to 2.5% of the mass of the added purified aqueous solution of monocyclic triazine, the reaction temperature is 120 °C to 150 °C, the reaction time is 2.0 h to 10.0 h, the dicarboxylic acid is one of adipic acid and glutaric acid, the higher fatty acid is one or more of lauric acid, myristic acid, palmitic acid, and stearic acid, and the catalyst is one or more of dodecylbenzenesulfonic acid, p-toluenesulfonic acid, and sulfamic acid; S3. Then add the cross-linked and oil-soluble desulfurizer and emulsifier to another part of the required amount of the purified aqueous solution of monocyclic triazine, and stir evenly to obtain a cross-linked composite desulfurizer, where the mass ratio of the added purified aqueous solution of monocyclic triazine to the cross-linked and oil-soluble desulfurizer is 1:0.2 to 1.0, and the addition amount of the emulsifier is 1% to 15% of the mass of the aqueous solution of monocyclic triazine.

2. The preparation method of the crosslinked composite desulfurizer according to claim 1, characterized in that In step S1, the alkanolamine is monoethanolamine and the aldehyde is formaldehyde.

3. The preparation method of the cross-linked composite desulfurizer according to claim 1 or 2, characterized in that In step S3, the emulsifier is one or more of sodium dodecyl sulfate, diethylene glycol monostearate, fatty alcohol polyoxyethylene ether, polyethylene glycol dilaurate, and polyglycerol ricinoleate.

4. A cross-linked composite desulfurizer prepared by the preparation method of the cross-linked composite desulfurizer according to any one of claims 1 to 3.