Copper-based coordination redox desulfurization solvent, preparation method and application

Abstract

The invention relates to the technical field of chemical engineering, and particularly discloses a copper-based coordination redox desulfurization solvent and a preparation method and application thereof.The preparation method comprises the following steps that copper chloride is added into 30 mL of dimethylformamide solvent, and a reagent A is prepared; adding an organic amine chelating agent into 10 mL of deionized water to prepare a preparation B; the reagent A and the reagent B are stirred at the normal temperature at the speed of 300 rpm until the reagent A and the reagent B are uniformly stirred and mixed to form a desulfurization system in which the organic solvent and the aqueous solution are mutually soluble. The desulfurizer has good desulfurization performance after regeneration, the regeneration effect of the desulfurizer is stable, and the desulfurizer can be recycled.

Description

Technical Field

[0001] The invention relates to the technical field of chemical engineering, and in particular to a copper-based coordinated redox desulfurization solvent, a preparation method and application thereof. Background Art

[0002] At present, copper-based coordinated redox desulfurization solvents play an important role in desulfurization technology, especially in the treatment of sulfur-containing compounds such as hydrogen sulfide. Desulfurization is usually achieved through coordinated redox reactions using the catalytic effect of copper-based catalysts.

[0003] However, in the prior art, the desulfurization of medium and small-scale sulfur-containing wellhead gas adopts water-phase oxidation desulfurization processes such as the Lo-cat method that combines desulfurization and sulfur recovery in one, which has the problems of poor stability of the desulfurizer and low sulfur capacity. Summary of the invention

[0004] The purpose of the present invention is to provide a copper-based coordinated redox desulfurization solvent, a preparation method and an application thereof, aiming to solve the technical problems that the desulfurization of medium and small-scale sulfur-containing wellhead gas in the prior art uses an aqueous phase oxidation desulfurization process such as the Lo-cat method that combines desulfurization and sulfur recovery in one, and the desulfurization agent has poor stability and low sulfur capacity.

[0005] To achieve the above object, the present invention adopts a method for preparing a copper-based coordinated redox desulfurization solvent, comprising the following steps:

[0006] Add copper chloride to 30 mL of dimethylformamide solvent to prepare reagent A;

[0007] Add an organic amine chelating agent to 10 mL of deionized water to prepare preparation B;

[0008] The reagent A and the reagent B are stirred at a speed of 300 rpm at room temperature until they are uniformly mixed to form a desulfurization system in which the organic solvent and the aqueous solution are miscible.

[0009] Wherein, the ratio of the cupric chloride to the organic amine chelating agent is 1:1.

[0010] The present invention also provides a copper-based coordinated redox desulfurization solvent, which is prepared by the preparation method of the copper-based coordinated redox desulfurization solvent as described above and comprises dimethylformamide, deionized water, copper chloride and an organic amine chelating agent.

[0011] The present invention also provides an application of a copper-based coordinated redox desulfurization solvent prepared by the method for preparing a copper-based coordinated redox desulfurization solvent as described above, which is applied to the regeneration and recycling of medium- and small-scale desulfurization of sulfur-containing wellhead gas.

[0012] The beneficial effects of the copper-based coordinated redox desulfurization solvent, preparation method and application of the present invention are as follows: copper ions in the desulfurization solvent first react with an organic amine chelating agent to form a binary complex, and then 2 After S enters the desulfurizer liquid phase, it relies on copper ions and H 2 The principle that S can react quickly to generate precipitation achieves the purpose of efficient desulfurization. After regeneration, copper ions and organic amine chelating agents are released into the solvent in large quantities, resulting in the desulfurizer having good desulfurization performance after regeneration. The regeneration effect of the desulfurizer is stable and can be recycled. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 This is a comparison chart of the desulfurization efficiency of different chelating agents for a copper-based coordinated redox desulfurization solvent of the present invention.

[0015] Figure 2 This is a comparison chart showing the effect of the amount of chelating agent added to the copper-based coordinated redox desulfurization solvent of the present invention on the desulfurization efficiency.

[0016] Figure 3 The present invention is a comparative diagram of the effects of different water contents on the desulfurization efficiency of a copper-based coordinated redox desulfurization solvent. DETAILED DESCRIPTION

[0017] See also Figures 1 to 3 , Figure 1 This is a comparison chart of the desulfurization efficiency of different chelating agents for a copper-based coordinated redox desulfurization solvent of the present invention. Figure 2 This is a comparison chart of the effect of the amount of chelating agent added to the copper-based coordinated redox desulfurization solvent on the desulfurization efficiency of the present invention. Figure 3 The present invention is a comparative diagram of the effects of different water contents on the desulfurization efficiency of a copper-based coordinated redox desulfurization solvent.

[0018] The present invention provides a method for preparing a copper-based coordinated redox desulfurization solvent, comprising the following steps:

[0019] Add copper chloride to 30 mL of dimethylformamide solvent to prepare reagent A;

[0020] Add an organic amine chelating agent to 10 mL of deionized water to prepare preparation B;

[0021] The reagent A and the reagent B are stirred at a speed of 300 rpm at room temperature until they are uniformly mixed to form a desulfurization system in which the organic solvent and the aqueous solution are miscible.

[0022] Furthermore, the ratio of the cupric chloride to the organic amine chelating agent is 1:1.

[0023] The present invention also provides a copper-based coordinated redox desulfurization solvent, which is prepared by the preparation method of the copper-based coordinated redox desulfurization solvent as described above and comprises dimethylformamide, deionized water, copper chloride and an organic amine chelating agent.

[0024] The present invention also provides an application of a copper-based coordinated redox desulfurization solvent prepared by the method for preparing a copper-based coordinated redox desulfurization solvent as described above, which is applied to the regeneration and recycling of medium- and small-scale desulfurization of sulfur-containing wellhead gas.

[0025] In this embodiment, the copper ions in the desulfurization solvent first react with the organic amine chelating agent to form a binary complex, and then 2 After S enters the desulfurizer liquid phase, it relies on copper ions and H 2 The principle that S can react quickly to generate precipitation achieves the purpose of efficient desulfurization. After regeneration, copper ions and organic amine chelating agents are released into the solvent in large quantities, resulting in the desulfurizer having good desulfurization performance after regeneration. The regeneration effect of the desulfurizer is stable and can be recycled.

[0026] Embodiment 1,

[0027] The copper-based coordinated redox desulfurization solvent prepared above was used for desulfurization operation. After the desulfurization started, the H in the tail gas was measured every 5 minutes. 2 S concentration until exhaust H 2 S concentration exceeds 20 mg / m 3 The desulfurization breakthrough stops. After the desulfurization experiment is over, the desulfurizer is directly connected to the outlet of the oxygen cylinder for regeneration experiment. The flow rate of pure oxygen is controlled to be 300mL / min, and the regeneration time is 4h. After the regeneration is completed, the desulfurizer is used again for desulfurization to test the recycling effect of the desulfurizer.

[0028] Experiments show that 40 mL of desulfurizer can desulfurize 5% H 2 The raw gas with S concentration was purified continuously for 400min, 160min and 130min at gas rates of 20mL / min, 40mL / min and 60mL / min respectively, and the static sulfur capacity reached 14.83g / L. The desulfurization regeneration effect was stable and could be recycled.

[0029] 1. Comparison of desulfurization efficiency of different chelating agents

[0030] Desulfurization agent preparation, take 2g CuCl2 The basic desulfurizer was dissolved in 30 mL of dimethylformamide and 10 mL of deionized water, and glycine, organic amine WN, and aminotrimethylenephosphoric acid were added in a molar ratio of 1:2 to copper ions to form three different desulfurizers.

[0031] Depend on Figure 1 It can be seen that the desulfurizer containing WN can maintain strict purification time for up to 160 minutes, which is better than the desulfurizer containing ATMP. The desulfurization product is initially a green solid, which turns into a black solid after the desulfurization is completed. After standing for a period of time, the solid and liquid are obviously separated. After regeneration for 4 hours at an oxygen flow rate of 300mL / min, the black solid disappears, a gray-green precipitate appears, and the color of the solution returns to the original solution color. From the above comparison, it can be seen that the desulfurizer containing WN chelating agent has a better effect.

[0032] 2. Effect of chelating agent dosage on desulfurization efficiency

[0033] Take 40mL of desulfurizer and change the amount of chelating agent to 0g, 0.5g, 1.0g, and 2.0g respectively. 2 S standard gas, desulfurization was carried out at 40 ° C and 40 mL / min gas rate. The desulfurization efficiency corresponding to different chelating agent additions is detailed in Figure 2 ;

[0034] It can be seen from the figure that as the amount of chelating agent increases, the desulfurizer maintains a strict degree of purification for a longer time. When the amount of chelating agent is 2g, the maximum desulfurization time is 160min. Subsequent series of experiments show that if the amount of chelating agent continues to increase, the increase in desulfurization time becomes slower. Therefore, the optimal amount of chelating agent is determined to be 2g.

[0035] 3. Effect of different water content on desulfurization efficiency

[0036] Take 40mL of desulfurizer, add 2g of chelating agent, and use 5% H 2 S standard gas, desulfurization absorption at 40℃, changing the moisture content in the desulfurizer to 0%, 25%, 50%, 75% and 100%. The desulfurization efficiency corresponding to different moisture contents is detailed in Figure 3 ;

[0037] As shown in the figure, when the moisture content in the desulfurizer is 0, the desulfurization time is 105 minutes. As the moisture content increases, the desulfurization time first increases to a maximum value of 160 minutes, at which time the corresponding moisture content is 25%.

[0038] What is disclosed above is only a preferred embodiment of the present invention, and it certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for preparing a copper-based coordinated redox desulfurization solvent, characterized in that: The steps include: Add copper chloride to 30 mL of dimethylformamide solvent to prepare reagent A; Add an organic amine chelating agent to 10 mL of deionized water to prepare preparation B; The reagent A and the reagent B are stirred at a speed of 300 rpm at room temperature until they are uniformly mixed to form a desulfurization system in which the organic solvent and the aqueous solution are miscible.

2. The method for preparing a copper-based coordinated redox desulfurization solvent according to claim 1, characterized in that: The ratio of the cupric chloride to the organic amine chelating agent is 1:

1.

3. A copper-based coordinated redox desulfurization solvent, prepared by the method for preparing a copper-based coordinated redox desulfurization solvent according to claim 1, characterized in that: It includes dimethylformamide, deionized water, cupric chloride and an organic amine chelating agent.

4. An application of a copper-based coordinated redox desulfurization solvent prepared by the method for preparing a copper-based coordinated redox desulfurization solvent as claimed in claim 1, characterized in that: It is used for regeneration and recycling of desulfurization of medium and small-scale sulfur-containing wellhead gas.

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