CN109381981B

CN109381981B - Novel desulfurizer and process for removing hydrogen sulfide by oxidation

Info

Publication number: CN109381981B
Application number: CN201710822295.4A
Authority: CN
Inventors: 余江; 商剑锋; 李佳璠; 程振华; 李文涛; 张晓东; 刘元直; 刘晓敏; 陈平文; 周政; 许艳赫
Original assignee: Beijing University of Chemical Technology; Sinopec Zhongyuan Oilfield Co Natural Gas Treatment Plant
Current assignee: Beijing University of Chemical Technology; Sinopec Zhongyuan Oilfield Co Natural Gas Treatment Plant
Priority date: 2017-08-10
Filing date: 2017-09-13
Publication date: 2021-05-28
Anticipated expiration: 2037-09-13
Also published as: CN109381981A

Abstract

The invention provides a novel desulfurizer and a process for removing hydrogen sulfide by oxidation, wherein the desulfurizer comprises an iron-based ionic liquid and a cosolvent, and preferably also comprises a defoaming agent, and the weight ratio of the iron-based ionic liquid to the cosolvent to the defoaming agent is 200: (1-80): (1-60). The process for removing hydrogen sulfide by oxidation adopts the desulfurizer, and hydrogen sulfide gas is introduced into the desulfurizer to remove the hydrogen sulfide. The non-aqueous phase desulfurization system constructed by the iron-based ionic liquid and the cosolvent has stable physicochemical properties and high-efficiency desulfurization performance, can overcome the problems of easy loss of a desulfurizing agent, complicated regulation and control of acidity and alkalinity, high water content of sulfur products and the like caused by the presence of water in the existing wet oxidation desulfurization process, can overcome the serious foaming problem caused by the desulfurizing agent and impurities after a set defoaming agent is further added, is a high-efficiency sulfur recycling technology, and has certain economic value and social benefit.

Description

Novel desulfurizer and process for removing hydrogen sulfide by oxidation

Technical Field

The invention belongs to the field of gas purification and pollution control in chemical processes, and particularly relates to a novel desulfurizer and a process for removing hydrogen sulfide by oxidation.

Background

In the present, petrochemical refining, natural gas extraction, biogas development and other processes, H is generated or released₂S。H₂S is a flammable acidic gas, which can form an explosive gas when mixed with air in a certain proportion and is flammable and explosive when exposed to open fire. At the same time, H₂After S is mixed with water vapor carried and generated in the industrial process, metal pipelines and detection equipment can be corroded, and part H₂Conversion of S to SO₂And then further corrode the equipment, causing plugging. H₂S is also a potent neurotoxin and when the concentration reaches 10ppm, the eyes and respiratory tract begin to be stimulated to some extent. At a concentration of 20ppm to 300ppm, dizziness, headache, olfaction pause and edema can be caused. When the concentration rises to 300ppm-500ppm, life danger can occur in short-term exposure, and timely treatment is needed. Above this concentration, lightning death occurs. Therefore, both environmental regulations and production safety require desulfurization and purification of hydrogen sulfide.

At home and abroad, the desulfurization technology is generally divided into dry desulfurization and wet desulfurization. Dry desulfurization is generally carried out on H by using a granular or powdery desulfurizing agent₂S is advancedThe process of adsorption, absorption or oxidation is carried out, but most of the dry desulfurizing agents are difficult to regenerate, easy to agglomerate and high in requirement on reaction temperature. The wet desulfurization is to utilize the absorption of H₂The process of absorbing or absorbing and oxidizing hydrogen sulfide by using the solvent or solution with the S characteristic, wherein the wet absorption method can realize sulfur resource recycling by combining with other oxidation technologies, and has high energy consumption and easy generation of secondary pollution. The wet oxidation method can independently realize the sulfur resource process, and the desulfurizer can be recycled.

The traditional wet oxidation technology is to perform an oxidation desulfurization process on the basis of a water phase, but because the reactions are all performed in a water solution and the desulfurization solution needs to be adjusted to be alkalescent, the desulfurization solution is easily diluted by the generated product water along with the desulfurization reaction and the regeneration cycle process of the desulfurizer. In addition, the raw gas generated in the industrial process is CO₂And higher water content, CO₂The mass ratio is between 0.1 and 65 percent, and the water content is between 0.01 and 15Kg/cm³。CO₂Can react with alkaline substances in the desulfurizer in a reverse and positive way to generate double salts, thereby affecting the acidity and alkalinity of the system and consuming the components of the desulfurization solution; the enrichment of water can cause the dilution of the desulfurizer, and influence the desulfurization performance. In order to compensate the desulfurization solution diluted by water, the desulfurization solution must be periodically supplemented and the process parameters such as pH value and the like must be regulated, which finally leads to the problems of complex process operation process, high purification cost, serious secondary pollution caused by a large amount of waste desulfurization solution, high sulfur water content and the like.

Meanwhile, the desulfurizing agent can generate certain foaming phenomenon in the desulfurization process. Heavy hydrocarbon substances and other impurities easily cause the foaming degree of the desulfurizer to be increased, further cause the problems of flooding, entrainment and the like, and cause the loss of the desulfurizer. Meanwhile, when foaming is serious, pressure loss in the reaction process can be obviously improved, and the production cost and equipment requirements are increased.

In order to overcome the problems and realize the process of high-efficiency sulfur resource, a new desulfurizer needs to be developed and a corresponding wet desulphurization green process needs to be constructed, the desulfurizer not only has the advantages of high efficiency and recycling of the traditional wet oxidation desulphurization, but also can overcome a series of problems caused by the existence of water, can realize the separation of the desulfurizer from the water through a simple separation process, and can effectively control the foaming degree; the green desulfurization process simultaneously meets the requirements of safety, reliability, no secondary pollution and low treatment cost.

Disclosure of Invention

In order to solve the above problems, the present inventors have conducted intensive studies and, as a result, have found that: the iron-based ionic liquid with stronger hydrophobic property, good oxidability and thermal stability is used as a desulfurizer, and meanwhile, the high-efficiency desulfurization of hydrogen sulfide is realized by setting conditions and adding a cosolvent and a defoamer, so that the problem of generation of a large amount of foams in the treatment process is solved; the treatment method has low cost, simple operation, no secondary pollution generation and regenerable desulfurizer, and avoids the influence on the subsequent industrial production popularization, thereby completing the invention.

The invention aims to provide the following technical scheme:

(1) the novel desulfurizer comprises the following components in parts by weight:

200 parts of iron-based ionic liquid;

and 1-80 parts of a cosolvent.

Wherein the iron-based ionic liquid is organic amine type iron-based ionic liquid, such as triethylamine hydrochloride iron-based ionic liquid Et₃NHFeCl₄；

The cosolvent is selected from any one or more of N, N-dimethylacetamide, N-dimethylformamide, tributyl phosphate and N-methylpyrrolidone propylene carbonate, is preferably selected from any one or a combination of N, N-dimethylacetamide and N, N-dimethylformamide, and is more preferably selected from N, N-dimethylacetamide;

preferably, the desulfurizing agent further comprises a defoaming agent, wherein the defoaming agent is selected from one or more of tributyl phosphate, an organic silicon defoaming agent, a polyether defoaming agent and a polyether compound organic silicon defoaming agent, and tributyl phosphate is preferred.

(2) A process for oxidative removal of hydrogen sulfide, preferably desulfurization using the desulfurizing agent according to (1) above, which comprises the steps of:

step 1, preparing a desulfurizing agent containing iron-based ionic liquid;

and 2, introducing the hydrogen sulfide gas into a desulfurizing agent to remove the hydrogen sulfide.

Wherein H is removed₂The reaction temperature of S is between 10 and 80 ℃, preferably between 20 and 40 ℃;

the desulfurization reaction is carried out for a set time, and then the desulfurizer is regenerated, preferably by introducing oxygen or air into the desulfurizer; the regeneration temperature is 10-60 ℃, and preferably 20-40 ℃.

The novel desulfurizer and the process for removing hydrogen sulfide by oxidation provided by the invention have the following beneficial effects:

(1) simple process and good safety: h removal by using multi-element system desulfurizer₂S, other auxiliary reagents do not need to be added, the pH value of the system does not need to be adjusted, and after a proper amount of specific defoaming agent is added into the iron-based ionic liquid, the desulfurizing agent can prevent the problems caused by foaming.

(2) Good absorption effect and strong oxidation property: the addition of the cosolvent improves the desulfurizing agent to H₂The absorption and solubility of S are favorable for the oxidation process, and the iron-based ionic liquid can well absorb H₂S is oxidized into sulfur;

especially, when the cosolvent is DMAC (N, N-dimethylacetamide) and the defoaming agent is TBP (tributyl phosphate), the DMAC can convert H₂Conversion of S to HS^-Promotion of H₂S is converted, TBP has the function of a cosolvent, and the improvement effect on the iron-based ionic liquid is stronger.

(3) The regeneration performance is good: the desulfurizer can be regenerated by oxygen or air, has better performance after regeneration, and realizes high-efficiency cyclic utilization.

Drawings

FIG. 1 shows the absorption of oxidation H according to the invention₂S, a process device diagram;

FIG. 2 shows Et synthesis from different raw material ratios₃NHFeCl₄A desulfurization performance comparison graph;

FIG. 3 shows different weight ratios Et₃NHFeCl₄: DMAC pair binaryDesulfurizing agent Et₃NHFeCl₄-DMAC desulfurization performance vs. map;

FIG. 4 shows Et at different temperatures₃NHFeCl₄-DMAC binary desulfurization agent desulfurization performance comparison plot;

FIG. 5A shows Et₃NHFeCl₄Cyclic voltammetry of (a);

FIG. 5B shows Et₃NHFeCl₄-cyclic voltammogram of DMAC binary desulfurization agent;

FIG. 6 shows Et₃NHFeCl₄-infrared spectrogram before and after desulfurization of DMAC binary desulfurizer;

FIG. 7 shows Et₃NHFeCl₄-DMAC binary desulfurization agent with Et₃NHFeCl₄-DMAC + 10% water desulfurization performance comparison plot;

FIG. 8 shows the high effect of the DMAC to TBP mixing ratio in the ternary desulfurization agent on foaming;

FIG. 9 shows the effect of the DMAC to TBP mixing ratio in the ternary desulfurization agent on desulfurization efficiency;

FIG. 10 shows a graph of desulfurization performance versus regeneration number.

The reference numbers illustrate:

1-a reactor;

2-a temperature control device;

3-a pump;

4-a gas supply device;

5-a gas flow meter;

6-tail gas absorption device.

Detailed Description

The features and advantages of the present invention will become more apparent and appreciated from the following detailed description of the invention.

In the present invention, it should be noted that the terms "connected" and "mounted" are used in a broad sense, and may be mechanically connected through a loose joint, a direct connection, or through other media. Those skilled in the art can understand the meaning of these terms in the present invention according to actual situations.

Because the traditional wet oxidation technology is in aqueous phaseOxidative desulfurization is carried out on a base basis, thereby causing subsequent multiple problems such as: the continuous addition of a medicament is needed to maintain the alkalescent environment of the system, the dilution loss of a desulfurizer, serious secondary pollution caused by a large amount of waste desulfurization solution, high sulfur water content and the like. Based on the problems, the invention provides a novel non-aqueous phase desulfurizer and a method for carrying out H by adopting the desulfurizer₂And (4) S removal process.

The invention aims to provide a novel non-aqueous phase desulfurizer, which comprises the following components in parts by weight:

200 parts of iron-based ionic liquid;

and 1-80 parts of a cosolvent.

Wherein the iron-based ionic liquid is organic amine type iron-based ionic liquid, such as triethylamine hydrochloride iron-based ionic liquid Et₃NHFeCl₄。

Further, the iron-based ionic liquid is prepared by reacting ferric trichloride, ferric nitrate or ferric sulfate with a target ligand (such as triethylamine hydrochloride), and is prepared by reacting Fe³⁺To Fe²⁺Is prepared by converting H₂And oxidizing the S gas into elemental S.

At present, research on hydrogen sulfide removal of iron-based ionic liquid is in a research stage, and more factors, such as the problem of high viscosity of the iron-based ionic liquid, need to be considered when the iron-based ionic liquid is used for industrial production. The high viscosity of the iron-based ionic liquid reduces the gas-liquid mass transfer efficiency and limits the conversion rate of hydrogen sulfide.

Aiming at the problem of the viscosity of the iron-based ionic liquid and the requirement for removing hydrogen sulfide, the inventor determines a method for adding a cosolvent into the iron-based ionic liquid. However, there are many kinds of organic solvents that can be used to reduce the viscosity of the iron-based ionic liquid, and few reports have been made to the solvent that can satisfy the requirement of not affecting the desulfurization effect or improving the desulfurization effect of the iron-based ionic liquid. Through a large number of researches and experiments, the invention determines to select any one or more of N, N-Dimethylacetamide (DMAC), N-Dimethylformamide (DMF), tributyl phosphate (TBP) and N-methylpyrrolidone (NMP) propylene carbonate as a cosolvent. The selected cosolvent has the following advantages:

(1) the viscosity is low;

(2) the high boiling point solvent can reduce the volatile loss of the organic solvent;

(3) strong capability of absorbing and dissolving hydrogen sulfide;

(4) the cosolvent has good intersolubility with the iron-based ionic liquid, and the system is not layered; the stability is good, the chemical composition of the iron-based ionic liquid is not changed, and the process of converting hydrogen sulfide into elemental sulfur is not influenced;

(5) the density of a mixed system obtained by mutual dissolution of the iron-based ionic liquid and the solid sulfur density (2.36 g.mL)^-1) Or molten sulfur density (1.8 g/mL)^-1) Has obvious difference, and is convenient for the separation of the generated elemental sulfur.

Further, the cosolvent is one or a combination of DMAC or DMF, preferably DMAC. DMAC is a polar organic solvent with high boiling point, low saturated vapor pressure and high thermal stability, so that DMAC has the advantages of difficult volatilization and loss and capability of meeting the requirement of industrial stability; meanwhile, DMAC has a hydrogen bond receptor, has the acid-binding effect and can bind H₂H-tethering in S to produce HS^-The root ion is shown as the formula (I). HS^-The root ions are easier to be absorbed by Fe in the iron-based ionic liquid³⁺Oxidation and therefore the combined use of DMAC promotes the desulfurization process.

In the invention, the weight ratio of the iron-based ionic liquid to the cosolvent is 200: (1-80). The inventor of the invention has found that only within the above range, the desulfurizing agent has a good desulfurizing effect on hydrogen sulfide. Within the above range, the desulfurization performance is improved first and then reduced as the proportion of the co-solvent is improved:

firstly, under the condition of low cosolvent proportion, the viscosity of the desulfurizer system is high, the cosolvent content is low, and the absorption capacity of the desulfurizer system for hydrogen sulfide is weak (if the cosolvent is DMAC, only a small part of absorbed hydrogen sulfide can generate an acid-binding effect and be converted into HS-). Gas-liquid mass transfer and hydrogen sulfide absorptionThe rate becomes the rate-determining step of the whole reaction process. Therefore, when the cosolvent proportion is increased, the desulfurization performance is greatly improved. When the cosolvent is further increased to 200:80, the effect of the cosolvent is no longer a step for restricting the desulfurization reaction, and Fe³⁺Oxidation of H₂The process of S becomes a speed-determining step, and this process is in conjunction with Fe³⁺There is a direct relationship with the concentration of (c). Although the desulfurization performance is reduced with the further improvement of the cosolvent proportion, the desulfurization curve is still stable and efficient, and the initial desulfurization (within 100 min) can reach 100 percent of desulfurization rate.

In a preferred embodiment, the weight ratio of the iron-based ionic liquid to the cosolvent is 200: (20-60), preferably 200: (30-40).

It is worth noting that the iron-based ionic liquid or the desulfurizer containing the iron-based ionic liquid generates more or less foam in the desulfurization process, and the serious foaming can cause the problems of flooding and the like, thereby causing the loss of the desulfurizer; at the same time, excessive foaming increases the pressure loss. In the invention, the defoaming agent is added to form a novel desulfurizing agent with a defoaming function, so that the generation of foam is inhibited in the desulfurization process.

In a preferred embodiment, the defoaming agent is any one or more selected from TBP, an organic silicon defoaming agent, a polyether defoaming agent and a polyether compound organic silicon defoaming agent. Among them, TBP is a low surface tension, and can rapidly defoam a formed foamed film in an unstable state, and in the present invention, the defoaming agent is preferably TBP in view of its low viscosity and its function of physically removing hydrogen sulfide.

In a preferred embodiment, after the defoamer is added, the weight ratio of the components in the desulfurizer is as follows:

200 parts of iron-based ionic liquid;

1-80 parts of a cosolvent;

1-60 parts of a defoaming agent.

Wherein the weight ratio of the iron-based ionic liquid to the total addition amount of the cosolvent and the defoaming agent is 200: (2-80), namely when the adding amount of the iron-based ionic liquid is 200 parts by weight, the iron-based ionic liquid is dissolvedThe total adding amount of the agent and the defoaming agent is not more than 80 parts by weight, so that excessive solvent is avoided being added, and Fe is reduced³⁺The concentration of (b) has a large influence on the desulfurization performance.

In a further preferred embodiment, when the iron-based ionic liquid is added in an amount of 200 parts by weight, the antifoaming agent is added in an amount of 10 to 50 parts by weight.

In a further preferred embodiment, when the iron-based ionic liquid is added in an amount of 200 parts by weight, the amount of the antifoaming agent is 20 to 40 parts by weight.

In another aspect of the invention, a process for removing hydrogen sulfide by oxidation by using the desulfurizing agent is provided. The process for removing hydrogen sulfide comprises the following steps:

step 1, preparing a desulfurizing agent containing iron-based ionic liquid;

In the step 1, synthesizing the iron-based ionic liquid, and uniformly mixing the iron-based ionic liquid and the cosolvent according to a set proportion to prepare the desulfurizer containing the iron-based ionic liquid.

In the invention, the iron-based ionic liquid is organic amine type iron-based ionic liquid, such as triethylamine hydrochloride iron-based ionic liquid Et₃NHFeCl₄。

When the iron-based ionic liquid is triethylamine hydrochloride iron-based ionic liquid, ferric trichloride, ferric nitrate or ferric sulfate reacts with triethylamine hydrochloride at 80 ℃ for 24 hours, and triethylamine hydrochloride iron-based ionic liquid Et is obtained after separation and purification₃NHFeCl₄。

In a preferred embodiment, the molar ratio of triethylamine hydrochloride to ferric ion is (1.2-1.7): 1.

when the molar ratio is lower than 1.2:1, solid still remains after stirring reaction for 24 hours, which indicates that FeCl₃Excess; when the molar ratio is higher than 1.7:1, the desulfurizing agent of the synthesized iron-based ionic liquid reduces the desulfurizing efficiency more rapidly along with the prolonging of time. This is mainly because the ferric iron oxidation desulfurization plays a major role in the whole desulfurization process, and the higher the ferric iron content is, the more desulfurization performance isAnd the excessive triethylamine hydrochloride reduces the content of ferric iron, thereby reducing the desulfurization performance.

In a further preferred embodiment, the molar ratio of triethylamine hydrochloride to ferric ion is (1.2-1.4): 1.

in a further preferred embodiment, the molar ratio of triethylamine hydrochloride to ferric ion is (1.2-1.3): 1.

in the invention, in order to reduce the viscosity of the prepared iron-based ionic liquid and increase the gas-liquid mass transfer efficiency, a cosolvent with low viscosity is added into the iron-based ionic liquid to form a binary desulfurizer. In the desulfurizing agent component, the cosolvent is selected from any one or more of N, N-Dimethylacetamide (DMAC), N-Dimethylformamide (DMF), tributyl phosphate (TBP) and N-methylpyrrolidone (NMP) propylene carbonate, preferably DMAC or DMF or any one or combination of DMAC and DMF, and more preferably DMAC.

Further, the weight ratio of the iron-based ionic liquid to the added cosolvent is 200: (1 to 80), preferably 200: (20-60), more preferably 200: (30-40).

In order to avoid the phenomena of flooding and the like caused by bubbles generated in the desulfurization process, a defoaming agent is further added into the iron-based ionic liquid. The defoaming agent is any one or more of TBP, an organic silicon defoaming agent, a polyether defoaming agent and a polyether compound organic silicon defoaming agent, and TBP is preferred.

Further, the weight ratio of the iron-based ionic liquid to the added defoaming agent is 200: (1-60), preferably 200: (10 to 50), more preferably 200: (20-40).

In step 2, the desulfurizing agent is charged into H₂In the S treatment system, H is introduced into the desulfurizer₂Gas of S, carrying out H₂And (4) removing the S.

In the invention, a setting processing system is adopted for H₂The structure of the treatment system is schematically shown in figure 1.

The treatment system comprises a reactor 1, a gas delivery device, and a temperature control device 2, wherein,

the reactor 1 comprises a cavity body with the upper end and the lower end capable of carrying out gas/liquid circulation, a desulfurizer is contained in the cavity body, the outer wall of the cavity body is of a sandwich structure, a liquid heat-conducting medium is filled in the sandwich layer, and the liquid heat-conducting medium and the cavity body of the reactor 1 carry out heat exchange;

the temperature control device 2 forms a circulating system with an outer wall interlayer of the reactor 1 through a pipeline, monitors the temperature of the liquid heat-conducting medium, and provides the liquid heat-conducting medium with set temperature to the outer wall interlayer of the reactor 1 through a pump 3 arranged on the pipeline;

preferably, the temperature control device 2 transfers the liquid heat-conducting medium to the lower part of the outer wall interlayer of the reactor 1, and recovers the liquid heat-conducting medium from the upper part of the outer wall interlayer;

the gas delivery device is communicated with the bottom of the reactor 1 through a pipeline to lead the H content₂The gas of the S passes through a desulfurizer from bottom to top, so that the desulfurization reaction time is prolonged; the gas conveying device comprises a gas supply device 4 and a gas flowmeter 5, and the gas flowmeter 5 monitors the gas flow in real time to enable the desulfurization reaction to be controllable.

Wherein said hydrogen atom contains₂H in S gas₂The volume concentration of S is 0-100%.

In a preferred embodiment, the bottom of the reactor 1 is provided with a sand core structure containing H₂The gas of S enters the reactor 1 from the bottom of the reactor 1, is divided into fine bubbles when passing through the sand core structure, and the reaction interface is increased after the gas enters the reactor 1 in the form of the fine bubbles, so that the H pair can be improved₂The removal rate of S.

In a preferred embodiment, the treatment system further comprises a tail gas absorption device 6, which is in communication with the reactor 1 above, for residual H₂And (4) removing S. The tail gas absorption device 6 can be another set of H containing iron-based ionic liquid desulfurizer₂And S, processing the system.

In the present invention, H is removed₂The reaction temperature of S is 10-80 ℃, preferably 20-40 ℃. The temperature is lower than 10 ℃, and the chemical reaction activity is low; the temperature is higher than 80 ℃, the solubility of the hydrogen sulfide is smaller, and part of the hydrogen sulfide is not dissolved and directly escapes from the desulfurizer. At 10-80 deg.C, especially 20-40 deg.C, to desulfurizing agentTo H₂The desulfurization effect of S is better.

In the present invention, the desulfurization reaction proceeds for a predetermined time and then follows Fe³⁺Gradual conversion to Fe²⁺The desulfurization efficiency is lowered, and regeneration of the desulfurizing agent is required. Further, the regeneration of the desulfurizing agent can be realized by introducing oxygen or air into the desulfurizing agent.

Preferably, the regeneration of the desulfurizing agent is achieved by feeding oxygen into the desulfurizing agent.

Under the condition of pure oxygen, the desulfurization solution can be basically completely regenerated, and only trace amount of Fe is contained²⁺Present in the system is essentially negligible. Under the condition of taking air as regeneration gas, the regeneration rate is relatively slow, and Fe with a certain concentration exists after regeneration²⁺There is, complete regeneration cannot be achieved. Mainly because the concentration of pure oxygen is 99.9 percent and the concentration of oxygen in air is 21 percent under the condition of the same air inflow, and the oxygen supply amount is a key factor for restricting regeneration. At the same time, N is in the air under the same residence time₂The presence of (B) reduces oxygen and Fe²⁺The probability of contact therefore limits the progress of the regeneration reaction.

In a preferred embodiment, the regeneration temperature is 10 to 60 ℃, preferably 20 to 40 ℃.

The rising of the temperature can improve the activity of the particles and can also enhance the gas-liquid mass transfer process, however, the temperature is over 60 ℃, and the regeneration performance is greatly influenced by the oxygen solubility and the foaming: firstly, the higher the temperature, the lower the oxygen solubility, which is not favorable for regeneration; secondly, the temperature increase produces a defoaming effect, and as the foam height decreases, the oxygen or air residence time decreases rapidly, so that the regeneration performance is influenced to some extent.

In the invention, the iron-based ionic liquid-cosolvent binary desulfurizer or the iron-based ionic liquid-cosolvent-defoamer ternary desulfurizer is adopted, and 100 percent of desulfurization can be still realized within 100min after at least 100 times of desulfurization-regeneration processes.

Examples

EXAMPLE 1 preparation of desulfurizing agent

1. Preparing an iron-based ionic liquid:

triethylamine hydrochloride and anhydrous ferric chloride are mixed according to a molar ratio of 1.2:1 reacting at 80 ℃ for 24h, separating and purifying to obtain triethylamine hydrochloride iron-based ionic liquid Et₃NHFeCl₄。

Et₃NHCl+FeCl₃→Et₃NHFeCl₄ (1)

2. Preparation of a desulfurizing agent:

and (2) uniformly mixing the iron-based ionic liquid and DMAC (dimethylacetamide) in a weight ratio of 200:20 to prepare the binary desulfurizer. The reaction in the desulfurizing tower is as follows:

H₂S(g)→H₂S(l) (2)，

H₂S+Fe(III)-Cl→Fe(II)-Cl+HCl+S₀ (3)，

and (3) total reaction: h₂S(g)+Fe(III)-Cl→HCl+S₀+Fe(II)-Cl (4)

EXAMPLE 2 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the iron-based ionic liquid, the molar ratio of triethylamine hydrochloride to anhydrous ferric trichloride is 1.3: 1.

EXAMPLE 3 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the iron-based ionic liquid, the molar ratio of triethylamine hydrochloride to anhydrous ferric trichloride is 1.4: 1.

EXAMPLE 4 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the iron-based ionic liquid, the molar ratio of triethylamine hydrochloride to anhydrous ferric trichloride is 1.5: 1.

EXAMPLE 5 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the iron-based ionic liquid, the molar ratio of triethylamine hydrochloride to anhydrous ferric trichloride is 1.6: 1.

EXAMPLE 6 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the iron-based ionic liquid, the molar ratio of triethylamine hydrochloride to anhydrous ferric trichloride is 1.7: 1.

EXAMPLE 7 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the binary desulfurizer, the iron-based ionic liquid and DMAC are uniformly mixed according to the weight ratio of 200: 40.

EXAMPLE 8 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the binary desulfurizer, the iron-based ionic liquid and DMAC are uniformly mixed according to the weight ratio of 200: 60.

Example 9 preparation of desulfurizing agent

The procedure for the preparation of the desulphurizing agent is as in example 1, except that: in the preparation of the binary desulfurizer, the iron-based ionic liquid and DMAC are uniformly mixed according to the weight ratio of 200: 80.

EXAMPLE 10 preparation of desulfurizing agent

1. Preparing an iron-based ionic liquid:

2. Preparation of a desulfurizing agent:

mixing the iron-based ionic liquid with DMAC and TBP according to the weight ratio of 200: 10: 50, and obtaining the ternary desulfurizer.

EXAMPLE 11 preparation of desulfurizing agent

The procedure for the preparation of the desulfurizing agent is the same as that of example 10 except that: in the preparation of the ternary desulfurizer, the iron-based ionic liquid, DMAC and TBP are uniformly mixed according to the weight ratio of 200:20: 40.

EXAMPLE 12 preparation of desulfurizing agent

The procedure for the preparation of the desulfurizing agent is the same as that of example 10 except that: in the preparation of the ternary desulfurizer, the iron-based ionic liquid, DMAC and TBP are uniformly mixed according to the weight ratio of 200:30: 30.

Example 13 preparation of desulfurizing agent

The procedure for the preparation of the desulfurizing agent is the same as that of example 10 except that: in the preparation of the ternary desulfurizer, the iron-based ionic liquid, DMAC and TBP are uniformly mixed according to the weight ratio of 200:40: 20.

Comparative example

Comparative example 1 preparation of desulfurizing agent

The procedure for the preparation of the desulfurizing agent is the same as that of example 10 except that: in the preparation of the desulfurizer, the iron-based ionic liquid, DMAC and TBP are uniformly mixed according to the weight ratio of 200:0: 60.

TABLE 1 EXAMPLES/COMPARATIVE EXAMPLES inventory Profile

Examples of the experiments

Characterization of the Infrared Spectrum

And (3) qualitatively analyzing the change of the functional groups of the desulfurizing agent before and after the reaction by using an infrared spectrometer. Tabletting with potassium bromide tabletting method, scanning frequency of 32 times, and resolution of 4cm^-1Wave number range of 400-4000 cm^-1。

Electrochemical-cyclic voltammetry

The redox performance of the desulfurizing agent was analyzed by cyclic voltammetry. An electrode system is composed of a platinum disk, a platinum sheet and Ag/AgCl, and a saturated KCl solution is a salt bridge.

Viscosity measurement

And (3) measuring the viscosity values of different systems by using a digital viscometer, and selecting proper rotors and rotating speeds according to the viscosity range. The temperature control adopts an external temperature control oil bath pan.

Oxidation Reduction Potential (ORP) measurement

And measuring the ORP of the desulfurizer by using an oxidation-reduction potentiometer, and recording and analyzing.

Determination of Total Organic Carbon (TOC) in tail gas absorption liquid

In order to determine the loss condition of the organic solvent in the desulfurization process, a TOC test analyzer is adopted to determine the TOC concentration in the tail gas absorption liquid. And (3) replacing hydrogen sulfide with nitrogen at different temperatures to simulate the desulfurization process, absorbing tail gas by using 100mL of deionized water, measuring the TOC content in 100mL of deionized water after the simulated desulfurization is finished, and calculating to obtain the loss of the organic solvent.

Desulfurization test device and desulfurization method

The desulfurization experimental device is mainly composed of a hydrogen sulfide gas cylinder (gas supply device), a gas flowmeter, an external circulation water bath (temperature control device), a bubbling glass reactor and a tail gas absorption device, as shown in figure 1. The outer layer of the reactor is a heating layer, and the inner layer is a reaction chamber.

The experiment is a comparative reference experiment, a proper amount of desulfurization solution is measured and added into a bubbling reactor, a certain reaction temperature and gas inlet flow are set, and a proper hydrogen sulfide concentration is selected. In the process of hydrogen sulfide removal, 50mL of desulfurization tail gas is extracted at regular time, and H of the desulfurization tail gas is measured₂The S concentration and the desulfurization efficiency were calculated as shown in the following formula.

Wherein C is an initial H₂Concentration of S, C_tFor H in the desulfurized tail gas at t moment₂The concentration of S.

Experimental example 1 DMAC vs H₂Absorption force test of S

DMAC is preferably a cosolvent in embodiments of the invention. To verify DMAC pair H₂The absorption force of S is that 20mLDMAC is injected into a glass reactor, the reaction temperature is 40 ℃, and the concentration H of 1000ppm₂S, the air inflow is 20mL min^-1While selecting another one as physical H removal in industry₂The solvent TBP for S is used as a comparative reference. The absorption results are shown in Table 2.

TABLE 2 DMAC and TBP absorption of H₂Tail gas concentration meter after S

As can be seen from Table 2, the absorption capacity of DMAC for hydrogen sulfide is stronger than that of the industrial physical absorption desulfurizing agent TBP. TBP as absorbent, mainlyThe molecular state of H is dissolved physically₂S absorption, while DMAC has not only a physical absorption of H₂S characteristics, and H₂The H element in S has certain chemical absorption capacity through strong chemical actions such as hydrogen bonds and the like. Thus the DMAC itself can be certified for H₂The absorption of S is beneficial to the process of absorption-oxidation of the composite desulfurizer.

Experimental example 2 raw material dosage ratio Et₃NHClFeCl₄Effect of desulfurization Performance

Experimental example 2.1 ORP potential test

In the invention, the iron-based ionic liquids prepared in examples 1 to 6 were subjected to Oxidation Reduction Potential (ORP) potential tests, and the results are shown in table 3 below.

TABLE 3 ORP values at different synthesis ratios

As can be seen from Table 3, following Et₃NHCl and FeCl₃The increase in the synthesis ratio tends to decrease the redox potential, mainly due to the decrease in the ferric iron density in the ionic liquid. H₂The potential for oxidizing S into sulfur is 141mV, theoretically, the oxidation process can be realized only if the potential is larger than the potential, the ORP value of an industrially common oxidant is between 200mV and 750mV and is lower than 200mV, and H is₂S is not easy to be oxidized, and is higher than 750mV, a by-product is easy to be generated, and H can be removed₂S is oxidized to sulfate, thiosulfate, and the like. The iron-based ionic liquid synthesized by the method meets the requirement of oxidizing H₂And (5) requirements of S.

Experimental example 2.2 removal of H from iron-based ionic liquid₂S test

In the invention, the iron-based ionic liquid prepared in the examples 1 to 6 is subjected to H removal₂And S testing. 30mL of iron-based ionic liquid with different synthesis ratios are respectively measured for desulfurization experiment, wherein H is 1 ‰ H₂S, inlet air flow of 40mL/min^-1The temperature was 30 ℃ and the desulfurization rate was varied with time as shown in FIG. 2.

As can be seen from the figure 2 of the drawings,h of each iron-based ionic liquid within at least 200min₂The S removal rate is kept above 95%, but the desulfurization efficiency is reduced with the time. The desulfurization efficiency of the iron-based ionic liquid with different synthesis ratios is prolonged backwards along with the improvement of the ratio of iron salt in the synthesis raw materials from the inflection point with low high variation. The method shows that the ferric iron oxidation desulfurization plays a main role in the whole desulfurization process, and the higher the ferric iron content is, the better the desulfurization performance is.

Experimental example 3 binary desulfurization agent test

Experimental example 3.1 iron-based Ionic liquid/cosolvent ratio vs. binary desulfurization agent dehydrogenation₂Influence of S

In the present invention, desulfurization experiments were conducted on the desulfurizing agents prepared in examples 1 and 7 to 9. Respectively injecting 10mL of binary desulfurizer with different compounding proportions into a glass reactor at 40 ℃ and 10000ppm of H₂The air inflow of S is 30mL min^-1Iron-based ionic liquid Et₃NHFeCl₄The effect of the compounding ratio with the co-solvent DMAC on desulfurization efficiency is shown in fig. 3.

As can be seen from FIG. 3, the desulfurization performance was improved and then reduced with the increase of the DMAC ratio, and the desulfurization performance was greatly improved when the DMAC ratio was continuously increased to 200:40, and when DMAC was increased to 200:60, 200:80, due to Fe³⁺The concentration is further lowered and the desulfurization performance is slightly lowered. But in Et₃NHFeCl₄The compounding ratio with DMAC is 200: (20-80), the desulfurization curve is stable and efficient, and the initial desulfurization period (within 100 min) can reach 100%.

Experimental example 3.2 DeH of binary desulfurizing agent by temperature₂Influence of S

The binary desulfurization agent prepared in example 7 was charged into a glass reactor under desulfurization conditions of 10000ppmH₂S, the air input is 30mL/min, and the reaction temperature is 20 ℃, 40 ℃ and 60 ℃ respectively. The desulfurization efficiency of the binary desulfurization agent was measured at different temperatures, respectively, and the results are shown in FIG. 4.

As shown in FIG. 4, at 20-60 ℃, the desulfurization efficiency can reach 100% within 100min and can be maintained at more than 95% within 200 min. Under the condition of long-time desulfurizationThe desulfurization effect is best at 40 ℃, mainly because: fe as the reaction proceeds³⁺The reaction rate is slow due to low temperature, so that the later desulfurization rate is reduced; the higher the temperature, H₂The smaller the solubility of S, the fraction H₂S is not dissolved and directly escapes from the desulfurizer, and the later desulfurization rate is also reduced.

Experimental example 3.3 physical and chemical Properties of binary desulfurizing agent

In the present invention, the physical and chemical properties of the iron-based ionic liquid and the desulfurizing agent obtained in example 7 were measured. The results of the measurements are shown in Table 4 below.

Table 4 physical parameter data

After the multi-element system is constructed, the physical and chemical properties can be changed to a certain extent, and the changes can play a very important role in the desulfurization performance and the behavior of the desulfurization process. In the non-aqueous phase wet desulphurization, the density, the viscosity and the oxidation-reduction potential are very important parameters, and have guiding significance for process design.

As can be seen from Table 4, the iron-based ionic liquid Fe³⁺The concentration can reach 3.0 mol.L^-1Fe in the above, binary desulfurizing agent³⁺The concentration can reach 2.0 mol.L^-1Above, high Fe³⁺The concentration can effectively increase H₂Conversion of S.

The density of the iron-based ionic liquid and the binary desulfurizer is between 1.0 and 1.3 g/mL^-1Obviously less than the density of solid sulfur of 2.36 g.mL^-1And a molten sulfur density of 1.8 g/mL^-1Therefore, no matter the sulfur sedimentation separation or the high-temperature melting sulfur separation is adopted, the effective separation can be obtained from the aspect of density, and the product extraction is realized.

Viscosity has a large relationship to the power cost in the production process, while temperature has the greatest effect on viscosity, so viscosity measurements were made at different temperatures. As can be seen from table 4, the addition of DMAC effectively reduced the viscosity of the iron-based ionic liquid, and as the temperature increased, the viscosity further decreased.

The oxidation-reduction potential ORP has important reference value for the evaluation of the oxidizability. H₂The potential at which S is oxidized to sulfur is 141mV, so theoretically, an oxidation process can be achieved only at a potential greater than this. The ORP of the iron-based ionic liquid and the binary desulfurizer system is 250-400 mV, so that the oxidation requirement can be well met, and the ORP is moderate in size and does not generate byproducts. It can also be seen that the ORP of the iron-based ionic liquid is greater than that of the compounded desulfurization system, which indicates that ORP and Fe are³⁺Is in positive correlation.

Experimental example 3.4 measurement of Cyclic voltammograms

Cyclic voltammetry was used for the cosolvent Et in example 7₃NHFeCl₄And iron-based ionic liquid Et₃NHFeCl₄And (4) carrying out electrochemical characterization on DMAC (dimethylacetamide), and analyzing the redox performance of the desulfurizing agent. An electrode system is composed of a platinum disk, a platinum sheet and Ag/AgCl, and a saturated KCl solution is a salt bridge. The setting conditions are as follows: scanning speed: 50 mV. s^-1(ii) a Temperature: 293K. The results are shown in FIGS. 5A and 5B.

As can be seen from fig. 5A and 5B, after the solvent is added to the iron-based ionic liquid, the oxidation peak position and the reduction peak position both shift to the left to some extent, which indicates that the iron-based ionic liquid can better perform the oxidative desulfurization process after adding DMAC. Meanwhile, it can be seen from the figure that the peak current of the desulfurizing agent is increased by about 2 times after adding DMAC, which indicates that the DMAC is added to facilitate the transfer of electrons, and the DMAC is mainly benefited from the effect of reducing the viscosity of the system. The viscosity is reduced, and the vicinity of the electrode e can be enhanced^-The transfer of (2) enables more particles on the surface of the electrode to participate in the oxidation-reduction process, so that the peak current is obviously improved after the DMAC is added.

EXAMPLE 3.5 stability determination

The stability of the desulfurizing agent is crucial to the realization of the desulfurization-regeneration process. The binary desulfurization agent of example 7 was subjected to infrared characterization before and after desulfurization, and the stability of the desulfurization agent was measured, and the results are shown in fig. 6.

As can be seen from FIG. 6, the number of peaks before and after the reaction of the desulfurizing agent, the peak position, and only the individual peak intensity have slight changes, which indicates that the framework is not damaged after the reaction, the system stability is good, and the requirement of desulfurization stability can be satisfied.

Experimental example 3.6 Effect of Water on binary desulfurization agent

Although the non-aqueous phase desulfurization is proposed in the invention, in industrial production, a certain amount of water is brought into a reaction system in the processes of gas source steam in natural gas acquisition and acidic water stripping in petroleum refining, so that the influence of water on the desulfurization performance needs to be researched.

10mL of the binary desulfurization agent Et obtained in example 7 was taken₃NHFeCl₄DMAC, adding 10% of deionized water (layering can be obviously seen after adding water), injecting the mixture into a glass reactor, wherein the reaction temperature is 40 ℃, the concentration of hydrogen sulfide is 10000ppm, and the air input is 30mL/min^-1The experimental results are shown in fig. 7.

The desulfurizer without water has a certain foaming phenomenon, the whole height is increased in the desulfurization process, which is equivalent to the tower height is increased, and the retention time is prolonged. The presence of water in the system after addition of water corresponds to an antifoaming agent, and the gas residence time is shorter than in the former, which may lead to the presence of traces of hydrogen sulfide.

As can be seen from FIG. 7, Et₃NHFeCl₄DMAC with water, the desulfurization effect is improved to some extent, contrary to what was speculated above, since with water it is possible to produce the intermediate Fe with high oxidation activity³⁺DMAC-OH or Fe (OH)²⁺Thereby improving the desulfurization performance and offsetting the loss of the desulfurization performance reduction caused by short gas retention time. Thus, with the above desulfurization system, water does not adversely affect desulfurization efficiency.

Experimental example 4 removal of H from ternary desulfurizing agent₂S

Experimental example 4.1 Effect of iron-based Ionic liquid-cosolvent-defoamer ratio on defoaming Property

The ternary desulfurization agents prepared in examples 8, 11, and 13 and comparative example 1 were subjected to surface tension and in-reactor foaming height tests, and the test results are shown in table 5 and fig. 8, respectively.

TABLE 5 Et₃NHFeCl₄DMAC-TBP surface tension meter with different mixing ratios

As is clear from Table 5, the desulfurizing agent surface tension decreased with the increase in the TBP ratio, and foaming was likely to occur easily. However, as can be seen from FIG. 8, the foam height during desulfurization decreased first and then increased as the TBP ratio increased, but did not exceed Et₃NHFeCl₄-height of DMAC system. The reason for the analysis may be: TBP is an organic solvent with low surface tension, and the defoaming principle is that a certain amount of TBP is quickly distributed on bubbles to ensure that the surface tension of the bubbles is not uniformly distributed, liquid flows to a high surface tension area, and the liquid film in a foam part area is not uniform in thickness to ensure that the bubbles are broken.

Experimental example 4.2 proportion of iron-based ionic liquid-cosolvent-defoamer to three-way desulfurizing agent de-H₂Influence of S

After the TBP is added, the foaming degree is effectively reduced, but whether the addition of the TBP has influence on the desulfurization performance needs to be verified through experiments. The influence of the TBP addition amount was measured by using the ternary desulfurization agents prepared in examples 10, 11, 12, and 13 and comparative example 1. The desulfurization experimental conditions were: 10000ppmH₂S, the air input is 40mL/min, and the reaction temperature is 30 ℃. The desulfurization performance ratio is shown in fig. 9.

As shown in FIG. 9, the desulfurization performance is slightly reduced with the increase of the TBP ratio, but the high-efficiency stable desulfurization can still be satisfied, and the desulfurization rate reaches 100% within 130min, namely, the addition of TBP has almost no influence on the desulfurization performance. In general, TBP is not only an effective defoamer, but also an excellent co-solvent.

Experimental example 5 test of regeneration Performance

In the present invention, the desulfurization test was performed on the desulfurizing agent obtained in example 7, and the desulfurized desulfurizing liquid was subjected to centrifugal separation of sulfur and then regenerated under pure oxygen. The desulfurization test was performed 3 times, and the regeneration test was performed 2 times. The desulfurization experimental condition was 10000ppm H₂S, the air input is 40mL/min, the reaction temperature is 20DEG C. The regeneration experimental conditions are that the regeneration gas is pure oxygen, the air input is 40mL/min, and the reaction temperature is 20 ℃. Detecting H in the tail gas after absorption every 10min₂The S content and the desulfurization efficiency are shown in FIG. 10.

As shown in fig. 10, the desulfurization performance of the fresh desulfurization solution was the best, and the desulfurization performance was somewhat degraded as the number of regeneration times was increased, but high-efficiency and stable desulfurization was still maintained. There may be two reasons for performance degradation: firstly can produce sulphur at the desulfurization in-process, though through sulphur separation before the regeneration, still have a certain amount of sulphur to exist in the desulfurization liquid, lead to the desulfurization liquid solid content to improve, the solid content improves can increase desulfurization liquid viscosity, influences the gas-liquid mass transfer process, and the cycle number is more, and the solid content is higher, and the performance degradation is more obvious. Secondly, along with the circulation of the regeneration desulfurization, a certain amount of DMAC (dimethylacetamide) is lost, so that the desulfurization performance is reduced. The above-mentioned reasons can be effectively avoided in practical production, and therefore, Et can be confirmed₃NHFeCl₄The DMAC system is excellent in the regeneration behaviour.

EXAMPLE 6 TOC determination and solvent loss

The non-aqueous phase wet desulphurization cannot separate the organic solvent, and although we choose the high-boiling-point organic solvent, the non-aqueous phase wet desulphurization still has certain volatilization loss. Because the relationship between the organic solvent loss and the inlet gas flow and the temperature is the largest, the loss conditions under different gas velocity and temperature conditions are determined and analyzed. The test group is the desulfurizing agent prepared in example 7; the control was pure DMAC solvent.

Influence of steam inflow: respectively injecting 20mL of liquid to be tested into the reactor, keeping the test temperature at 40 ℃, setting different inlet gas flow rates to be 30-210 mL/min, ventilating for 1h, absorbing tail gas by deionized water, carrying out TOC (total organic carbon) determination on the absorption liquid, and calculating corresponding DMAC (dimethylacetamide) loss amounts as shown in tables 6 and 7.

TABLE 6 loss of data Table for pure DMAC at different air intakes

TABLE 7 Et₃NHFeCl₄DMAC loss data table at different air intakes

As can be seen from tables 6 and 7, the DMAC loss increases with the increase of the air intake, wherein the pure DMAC system has the maximum loss of 210mL/min^-1Ventilating for 1h under the air inflow of 1h, and the loss ratio is 0.5 per mill. Et (Et)₃NHFeCl₄The loss of the DMAC system is lower than that of the pure DMAC system, and the DMAC system is used for controlling the flow rate of the DMAC system at a high air intake of 210 mL-min^-1The air is ventilated for 1 hour under the air input of 1 hour, the loss ratio is less than 0.2 per mill, which indicates that the loss of the solvent in the desulfurizer is less.

Reaction temperature effects: respectively injecting 20mL of liquid to be tested into the reactor, keeping the nitrogen flow at 60mL/min, setting different test temperatures at 30-80 ℃, ventilating for 1h, absorbing tail gas by ultrapure water, measuring TOC of the absorption liquid, and calculating corresponding loss amounts as shown in tables 8 and 9.

TABLE 8 table of loss of flow data for pure DMAC at different temperatures

TABLE 9 Et₃NHFeCl₄DMAC loss data Table at No temperature

From tables 8 and 9 above, it can be seen that the effect of the gas flow on the DMAC loss in different systems is much less than the temperature effect. Pure DMAC and Et at different temperatures₃NHFeCl₄The DMAC system has large difference of loss proportion and loss amount by about 10 times. Description of DMThe saturated vapor pressure of the AC and the iron-based ionic liquid is greatly changed before and after mutual solubility. The saturated vapor pressure of the iron-based ionic liquid as room-temperature molten salt is almost zero, the saturated vapor pressure of pure DMAC is higher, and the defect can be well overcome after compounding, so that the desulfurizer is not easy to lose.

Claims

1. The process for removing hydrogen sulfide by using the desulfurizer through oxidation is characterized in that the desulfurizer comprises the following components in parts by weight:

200 parts of iron-based ionic liquid;

40 parts of a cosolvent;

20 parts of a defoaming agent, namely 20 parts of,

the iron-based ionic liquid is triethylamine hydrochloride iron-based ionic liquid Et₃NHFeCl₄(ii) a The cosolvent is N, N-dimethylacetamide;

the defoaming agent is tributyl phosphate;

the process comprises the following steps:

step 1, synthesizing iron-based ionic liquid, uniformly mixing the iron-based ionic liquid and a cosolvent according to a set proportion, and adding a defoaming agent to prepare a desulfurizing agent containing the iron-based ionic liquid;

triethylamine hydrochloride iron-based ionic liquid Et is obtained by the reaction of ferric trichloride, ferric nitrate or ferric sulfate and triethylamine hydrochloride₃NHFeCl₄The molar ratio of triethylamine hydrochloride to ferric ions is 1.2: 1;

step 2, introducing hydrogen sulfide gas into a desulfurizer to remove hydrogen sulfide and H₂The reaction temperature of S is between 20 and 40 ℃;

and (3) regenerating the desulfurizer after the desulfurization reaction is carried out for a set time, and introducing oxygen into the desulfurizer to realize the regeneration of the desulfurizer, wherein the regeneration temperature is 20-40 ℃.