Crude oil desulfurizing agent as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of oil exploitation, and particularly relates to a crude oil desulfurizer and a preparation method and application thereof. The preparation method comprises the following steps: in a water phase, cyanuric chloride and 1, 4-bis (3-aminopropyl) piperazine are subjected to a first substitution reaction; secondly, the first substitution reaction product and 4-methyl-1-piperazine ethylamine are subjected to a second substitution reaction; thirdly, the second substitution reaction product and aminoethanol are subjected to a third substitution reaction, and the product desulfurizer is obtained. The desulfurizer is wide in raw material source, simple in synthesis process and clean and pollution-free in process; meanwhile, the desulfurizing agent has a good desulfurizing effect, and the highest sulfur capacity reaches 41.2%.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum extraction, and specifically relates to a crude oil desulfurizer and a preparation method and application thereof. Background Art

[0002] As global energy demand continues to grow, crude oil production continues to increase, and the sulfur content in crude oil is also on the rise. The crude oil produced and imported by many countries and regions is mostly medium-high sulfur crude oil with a high sulfide content. These sulfides are characterized by malodor, toxicity and strong corrosiveness, which brings serious safety problems to oil field production and oil and gas gathering and transportation.

[0003] Organic sulfur in crude oil will also produce hydrogen sulfide after high temperature or water thermal cracking. Crude oil contains a small amount of water, hydrogen sulfide and carbon dioxide, two acidic gases dissolved in it during the extraction process, which will synergistically corrode steel, shorten the service life of pipelines and storage tanks, and even cause oil pipeline leakage; in addition, the escape of hydrogen sulfide during transportation will not only cause danger to workers, but also lead to catalyst poisoning in subsequent crude oil processing equipment. Therefore, it is particularly important to desulfurize oil, gas and sewage.

[0004] In order to cope with the challenges brought by sulfides, crude oil desulfurization technology came into being. As one of the important means, crude oil desulfurizer has the advantages of small addition amount and convenient operation, and is widely used in the crude oil desulfurization process.

[0005] CN107081041A discloses a hydrogen sulfide gas absorbent and its application. This crude oil desulfurizer has a good desulfurization effect, but the patent contains triazine with poor water solubility. Currently, various co-solvents are generally added to improve its water solubility at home and abroad. Conventional mutual solvents include small molecule alcohols and ethers. However, the addition of these co-solvents affects the sulfur capacity of the desulfurizer and also reduces the absorption rate of the desulfurizer for oil and gas hydrogen sulfide.

[0006] CN115651696B discloses a desulfurizer for liquefied petroleum gas and a preparation method thereof, belonging to the field of petrochemical technology. The desulfurizer uses expanded graphite as a matrix, and undergoes reflux oxidation, doping and composite, epoxy modification and grafting modification treatments in sequence. Through composite doping with manganese, titanium and cerium, an adsorption-activation-doping system is formed to improve the physical adsorption performance of the matrix to sulfides; through the characteristics of KH560 in a weak acid and weak base environment, epoxy groups are introduced to the surface of the composite matrix, and then hydroxyethyl hexahydro-s-triazine is used to open the ring with the epoxy group under the catalysis of strongly alkaline potassium tert-butoxide, and a triazine ring structure is grafted onto the surface, which can directly react with sulfides to achieve the effect of chemical desulfurization. However, the desulfurization rate of the desulfurizer is not high in production, and the dosage is large. Summary of the invention

[0007] The present invention aims to provide a crude oil desulfurizer and its preparation method and application in view of the shortcomings of the prior art. The crude oil desulfurizer of the present invention has the advantages of wide raw material sources, simple synthesis process, clean and pollution-free process and good desulfurization effect.

[0008] In order to achieve the above objectives:

[0009] In a first aspect, the present invention discloses a method for preparing a crude oil desulfurizer, the preparation method comprising: in an aqueous phase, cyanuric chloride and 1,4-bis(3-aminopropyl)piperazine undergo a first substitution reaction; secondly, the first substitution reaction product undergoes a second substitution reaction with 4-methyl-1-piperazineethylamine; and thirdly, the second substitution reaction product undergoes a third substitution reaction with aminoethanol to obtain a product desulfurizer.

[0010] In the present invention, preferably, based on 1 mole of cyanuric chloride, the amounts of 1,4-bis(3-aminopropyl)piperazine, 4-methyl-1-piperazineethylamine and aminoethanol are 0.4-0.6 mole, 0.8-1.2 mole and 0.8-1.2 mole, respectively.

[0011] More preferably, based on 1 mol of cyanuric chloride, the amounts of 1,4-bis(3-aminopropyl)piperazine, 4-methyl-1-piperazineethylamine and aminoethanol are 0.45-0.55 mol, 0.9-1.1 mol and 0.9-1.1 mol, respectively.

[0012] In the present invention, preferably, the mass ratio of water to cyanuric chloride in the aqueous phase is 30-35:1.

[0013] In the present invention, preferably, the first substitution reaction temperature is lower than 5° C., and the reaction time is 10-60 min.

[0014] More preferably, the first substitution reaction temperature is lower than 3°C, and the reaction time is 20-50 min.

[0015] In the present invention, preferably, the second substitution reaction temperature is 10-30° C., and the reaction time is 0.5-4 h.

[0016] More preferably, the second substitution reaction temperature is lower than 15-25°C, and the reaction time is 1-3h.

[0017] In the present invention, preferably, the third substitution reaction temperature is 60-80° C., and the reaction time is 1-12 h.

[0018] More preferably, the third substitution reaction temperature is lower than 70-80°C, and the reaction time is 3-10h.

[0019] According to a more specific preferred embodiment, the preparation method of the desulfurizing agent specifically comprises the following steps:

[0020] (1) Add cyanuric chloride and water to the reactor in sequence, stir and slurry, cool it to below 2°C with ice brine, add 1,4-bis(3-aminopropyl)piperazine dropwise, control the reaction temperature to be below 5°C, the reaction time is 10-60 min, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0021] (2) Add 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 10-30°C, the reaction time to 0.5-4h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0022] (3) Add aminoethanol to the above reactor, control the reaction temperature to 60-80°C, the reaction time to 1-12h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0023] (4) The mixed solution is cooled to below 5°C, the solid is precipitated by cooling, filtered, and dried at 105-110°C overnight to obtain a desulfurizing agent product.

[0024] The reaction equation for the synthesis of the desulfurizing agent of the present invention is as follows:

[0025]

[0026] In another aspect, the present invention discloses a crude oil desulfurizer, the molecular structure of the desulfurizer is as follows:

[0027]

[0028] In a third aspect, the present invention discloses the application of the above desulfurizer in the treatment of hydrogen sulfide in oil and gas wells.

[0029] The 1,4-bis(3-aminopropyl)piperazine and 4-methyl-1-piperazineethylamine introduced in the reaction of the present invention belong to a composite desulfurization functional group: piperazine can completely remove hydrogen sulfide, and the product after piperazine desulfurization can adsorb hydrogen sulfide; the aminoethanol introduced in the reaction of the present invention contains hydroxyl and amino groups, belongs to a polar molecule, and has good dissolving and adsorption effects on polar molecule hydrogen sulfide.

[0030] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0031] (1) The raw materials for preparing the desulfurizer of the present invention are widely available, the synthesis process is simple, and the process is clean and pollution-free;

[0032] (2) The desulfurizing agent of the present invention has good desulfurization effect, and the maximum sulfur capacity reaches 41.2%. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The present invention discloses a device for measuring the sulfur content of a desulfurizing agent. DETAILED DESCRIPTION

[0034] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0035] The present invention will be further described below in conjunction with specific embodiments:

[0036] Example 1

[0037] (1) 0.1 mol of cyanuric chloride and 552 g of water were added to the reactor in sequence, stirred and slurried, cooled to below 2° C. with ice brine, 0.04 mol of 1,4-bis(3-aminopropyl)piperazine was added dropwise, the reaction temperature was controlled to be below 5° C., the reaction time was 10 min, and sodium hydroxide solution was added dropwise at the same time to maintain the pH at 6-7;

[0038] (2) Add 0.08 mol of 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 10°C, the reaction time to 0.5 h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0039] (3) Add 0.08 mol of aminoethanol to the above reactor, control the reaction temperature to 60°C, the reaction time to 1 hour, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0040] (4) The mixed solution was cooled to below 5°C, the solid was precipitated by cooling, filtered, and dried at 105°C overnight to obtain a desulfurizing agent product.

[0041] Example 2

[0042] (1) 0.1 mol of cyanuric chloride and 585 g of water were added to the reactor in sequence, stirred and slurried, cooled to below 2° C. with ice brine, 0.045 mol of 1,4-bis(3-aminopropyl)piperazine was added dropwise, the reaction temperature was controlled to be below 4° C., the reaction time was 20 min, and sodium hydroxide solution was added dropwise at the same time to maintain the pH at 6-7;

[0043] (2) Add 0.085 mol of 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 10°C, the reaction time to 1 hour, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0044] (3) Add 0.115 mol of aminoethanol to the above reactor, control the reaction temperature to 65°C, the reaction time to 2h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0045] (4) The mixed solution was cooled to below 5°C, the solid was precipitated by cooling, filtered, and dried at 105°C overnight to obtain a desulfurizing agent product.

[0046] Example 3

[0047] (1) 0.1 mol of cyanuric chloride and 582 g of water were added to the reactor in sequence, stirred and slurried, cooled to below 2° C. with ice brine, 0.058 mol of 1,4-bis(3-aminopropyl)piperazine was added dropwise, the reaction temperature was controlled to be below 5° C., the reaction time was 30 min, and sodium hydroxide solution was added dropwise at the same time to maintain the pH at 6-7;

[0048] (2) Add 0.12 mol of 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 20°C, the reaction time to 2h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0049] (3) Add 0.085 mol of aminoethanol to the above reactor, control the reaction temperature to 70°C, the reaction time to 5 h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0050] (4) The mixed solution was cooled to below 5°C, the solid was precipitated by cooling, filtered, and dried at 106°C overnight to obtain a desulfurizing agent product.

[0051] Example 4

[0052] (1) 0.1 mol of cyanuric chloride and 644 g of water were added to the reactor in sequence, stirred and slurried, cooled to below 2° C. with ice brine, 0.06 mol of 1,4-bis(3-aminopropyl)piperazine was added dropwise, the reaction temperature was controlled to be below 3° C., the reaction time was 40 min, and sodium hydroxide solution was added dropwise at the same time to maintain the pH at 6-7;

[0053] (2) Add 0.105 mol of 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 15°C, the reaction time to 2.5 h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0054] (3) Add 0.12 mol of aminoethanol to the above reactor, control the reaction temperature to 80°C, the reaction time to 8h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0055] (4) The mixed solution was cooled to below 5°C, the solid was precipitated by cooling, filtered, and dried at 108°C overnight to obtain a desulfurizing agent product.

[0056] Example 5

[0057] (1) 0.1 mol of cyanuric chloride and 613 g of water were added to the reactor in sequence, stirred and slurried, cooled to below 2° C. with ice brine, 0.048 mol of 1,4-bis(3-aminopropyl)piperazine was added dropwise, the reaction temperature was controlled to be below 4° C., the reaction time was 50 min, and sodium hydroxide solution was added dropwise at the same time to maintain the pH at 6-7;

[0058] (2) Add 0.09 mol of 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 20°C, the reaction time to 3 hours, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0059] (3) Add 0.09 mol of aminoethanol to the above reactor, control the reaction temperature to 75°C, the reaction time to 10 h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0060] (4) The mixed solution was cooled to below 5°C, the solid was precipitated by cooling, filtered, and dried at 105°C overnight to obtain a desulfurizing agent product.

[0061] Example 6

[0062] (1) 0.1 mol of cyanuric chloride and 600 g of water were added to the reactor in sequence, stirred and slurried, cooled to below 2° C. with ice brine, 0.052 mol of 1,4-bis(3-aminopropyl)piperazine was added dropwise, the reaction temperature was controlled to be below 5° C., the reaction time was 60 min, and sodium hydroxide solution was added dropwise at the same time to maintain the pH at 6-7;

[0063] (2) Add 0.095 mol of 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 20°C, the reaction time to 4 hours, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0064] (3) Add 0.1 mol of aminoethanol to the above reactor, control the reaction temperature to 65°C, the reaction time to 6 hours, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0065] (4) The mixed solution was cooled to below 5°C, the solid was precipitated by cooling, filtered, and dried at 110°C overnight to obtain a desulfurizing agent product.

[0066] Example 7

[0067] (1) 0.1 mol of cyanuric chloride and 612 g of water were added to the reactor in sequence, stirred and slurried, cooled to below 2° C. with ice brine, 0.05 mol of 1,4-bis(3-aminopropyl)piperazine was added dropwise, the reaction temperature was controlled to be below 3° C., the reaction time was 30 min, and sodium hydroxide solution was added dropwise at the same time to maintain the pH at 6-7;

[0068] (2) Add 0.1 mol of 4-methyl-1-piperazineethylamine to the above reactor, control the reaction temperature to 30°C, the reaction time to 2h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 6-7;

[0069] (3) Add 0.105 mol of aminoethanol to the above reactor, control the reaction temperature to 70°C, the reaction time to 12 h, and simultaneously add sodium hydroxide solution dropwise to maintain the pH at 7-8;

[0070] (4) The mixed solution was cooled to below 5°C, the solid was precipitated by cooling, filtered, and dried at 107°C overnight to obtain a desulfurizing agent product.

[0071] Example 8 Sulfur Capacity Test

[0072] Sulfur capacity is one of the most important indicators for evaluating the performance of a desulfurizer. The sulfur capacity of the desulfurizer of the present invention is tested with reference to Q / SH10202872-2021 "General Technical Conditions for Desulfurizers", and the triazine desulfurizer of Shengli Oilfield Jindao Petroleum Engineering Technology Co., Ltd. is used as a comparative example. The test results are shown in Table 1.

[0073] (1) Absorption of hydrogen sulfide

[0074] according to Figure 1 According to the requirements, the device is connected in a fume hood. Weigh 10g of the desulfurizer to be tested, add it to the hydrogen sulfide absorption reaction bottle, add 400g of distilled water, put in a sintered filter element so that it is placed close to the bottom (3-5mm) of the absorption reaction bottle, and connect it to the outlet of the hydrogen sulfide cylinder through a pipeline, so that the filter element is completely immersed in the liquid, and the top of the filter element is 15mm below the liquid level of the desulfurizer dilution solution. Add a rubber stopper to the upper part of the absorption tube, leaving a gas outlet, which is connected to the silver nitrate solution and the sodium hydroxide solution in turn. Weigh the mass of the hydrogen sulfide absorption reaction bottle and the sintered filter element, which is m 0 .

[0075] Place the hydrogen sulfide absorption reaction bottle in a constant temperature water bath at 60℃±1℃, and make the liquid level of the water bath higher than the level of the desulfurizer dilution solution by more than 20mm. After keeping the constant temperature for at least 15 minutes, start injecting hydrogen sulfide or hydrogen sulfide gas balanced by inert gas into the absorption tube, and control the gas injection speed to no more than 20mL / min through the flow meter. Weigh the mass of the hydrogen sulfide absorption reaction bottle (including the desulfurizer, distilled water and filter element) every 30 minutes until the mass of the absorption reaction bottle does not increase, recorded as m1 .

[0076] At the same time, the mass of the absorption reaction bottle before and after the reaction (including distilled water and filter element) was measured when only 400g of distilled water was added without adding desulfurizer. 0 and n 1 .

[0077] (2) Calculation of sulfur capacity

[0078] The sulfur capacity is calculated according to formula (1):

[0079]

[0080] Where:

[0081] X—desulfurization agent sulfur content, %;

[0082] m 0 —Weight of absorption reaction bottle before the experiment (including desulfurizer, distilled water and filter element), g;

[0083] m 1 —Mass of the absorption reaction bottle after the experiment (including desulfurizer, distilled water and filter element), g;

[0084] m—mass of the desulfurizer to be tested, g;

[0085] n 0 —The mass of the absorption reaction bottle before the experiment (including distilled water and filter element), g;

[0086] n 1 —The mass of the absorption reaction bottle after the experiment (including distilled water and filter element), g.

[0087] Table 1 Sulfur capacity test results

[0088] Sulfur capacity R, % Example 1 36.2 Example 2 38 Example 3 37.3 Example 4 39.3 Example 5 40 Example 6 40.8 Example 7 41.2 Comparative Example 26

[0089] It can be seen from Table 1 that the sulfur capacity of the desulfurizer of the present invention (Examples 1-7) is greater than 36%, with the highest reaching 41.2% (Example 7); while the sulfur capacity of the comparative example is 26%. The desulfurization effect of the desulfurizer of the present invention is significantly better than that of the comparative example.

[0090] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing a crude oil desulfurizer, characterized in that: The preparation method comprises: in an aqueous phase, cyanuric chloride and 1,4-bis(3-aminopropyl)piperazine undergo a first substitution reaction; secondly, the first substitution reaction product undergoes a second substitution reaction with 4-methyl-1-piperazineethylamine; thirdly, the second substitution reaction product undergoes a third substitution reaction with aminoethanol to obtain a product desulfurizer; Based on 1 mole of cyanuric chloride, the amounts of 1,4-bis(3-aminopropyl)piperazine, 4-methyl-1-piperazineethylamine and aminoethanol are 0.4-0.6 mole, 0.8-1.2 mole and 0.8-1.2 mole respectively.

2. The preparation method according to claim 1, characterized in that: Based on 1 mole of cyanuric chloride, the amounts of 1,4-bis(3-aminopropyl)piperazine, 4-methyl-1-piperazineethylamine and aminoethanol are 0.45-0.55 mole, 0.9-1.1 mole and 0.9-1.1 mole respectively.

3. The preparation method according to claim 1, characterized in that: The first substitution reaction temperature is lower than 5°C, and the reaction time is 10-60 minutes.

4. The preparation method according to claim 3, characterized in that: The first substitution reaction temperature is lower than 3°C, and the reaction time is 20-50 minutes.

5. The preparation method according to claim 1, characterized in that: The second substitution reaction temperature is 10-30°C, and the reaction time is 0.5-4h.

6. The preparation method according to claim 5, characterized in that: The second substitution reaction temperature is lower than 15-25° C., and the reaction time is 1-3 hours.

7. The preparation method according to claim 1, characterized in that: The third substitution reaction temperature is 60-80°C and the reaction time is 1-12h.

8. The preparation method according to claim 7, characterized in that: The third substitution reaction temperature is lower than 70-80°C, and the reaction time is 3-10h.

9. A crude oil desulfurizer, characterized in that: The molecular structural formula of the desulfurizer is as follows:

10. Use of the desulfurizer according to claim 9 in the treatment of hydrogen sulfide in oil and gas wells.

Images