Stabilizer, desulfurizing agent for liquid-phase redox desulfurization process and application

Abstract

The invention discloses a stabilizer, a desulfurizing agent for a liquid-phase redox desulfurization process and application. The stabilizer comprises humic acid and alcohol amine, and the number of carbon atoms of the alcohol amine is 1-8. The stabilizer disclosed by the invention can effectively enhance the stability of iron-containing substances in the desulfurizing agent for the liquid-phase redox desulfurization process in an alkaline environment, not only can effectively ensure the catalytic desulfurization effect of the desulfurizing agent, but also is beneficial to reducing the use amount of the iron-containing substances.

Description

Technical Field

[0001] This invention relates to a stabilizer, a desulfurizing agent for liquid-phase oxidation-reduction desulfurization processes, and their applications, belonging to the field of catalytic materials technology. Background Technology

[0002] The desulfurization catalyst used in liquid-phase redox desulfurization processes is a coordinated iron catalyst. Currently, the most widely used iron-based catalytic system in liquid-phase redox desulfurization processes is ethylenediaminetetraacetic acid (EDTA)-iron coordination compounds. These catalysts use EDTA or its corresponding salts (such as disodium or tetrasodium EDTA). Furthermore, these catalysts typically require an alkaline environment to participate in the liquid-phase catalytic reaction. However, these catalysts are extremely unstable in strongly alkaline solutions (pH greater than 9), easily forming iron hydroxide precipitates. Simultaneously, the oxygen free radicals (O*) generated during the oxidation of sulfide to elemental sulfur readily attack the CN bonds in EDTA, leading to CN bond breakage, disrupting the structure of EDTA, and causing it to lose its coordination function. This further results in the formation of iron hydroxide precipitates, making catalyst regeneration difficult and increasing catalyst usage. Therefore, there is an urgent need to introduce a highly efficient component that can effectively prevent the formation of iron hydroxide precipitates in strongly alkaline solutions and reduce the attack of O* on EDTA during the catalytic reaction.

[0003] Chinese invention patent CN109603487B discloses a desulfurizing agent for a liquid-phase oxidative desulfurization process, comprising the following components: a chelated iron catalyst, a stabilizer, an alkaline solution, and water; wherein the chelated iron catalyst is at least one of HEDP, EDTMPS, DTPMPA, EDDHA, STPP, NTA, Na3NTA, EDTA, HEDTA, Na3HEDTA, Na4EDTA, sodium gluconate, sodium metasilicate, potassium tartrate, and sodium citrate as a ligand with soluble iron salts FeCl3, Fe2(SO4)3, Fe( The desulfurizing agent is a chelate of at least one of NO3 and FeNH4(SO4), with a ligand / Fe molar ratio of 1 to 10. The stabilizer comprises the following components: any one of N,N-dihydroxyethylglycine and its salts, morpholine, and tert-butanol. The molar ratio of N,N-dihydroxyethylglycine and its salts to the total iron in the chelated iron catalyst is (0.5-5):1; the molar ratio of morpholine to the total iron in the chelated iron catalyst is (0.5-5):1; and the molar ratio of tert-butanol to the total iron in the chelated iron catalyst is 1:(1-5). The pH of the desulfurizing agent system is 8-10. The desulfurizing agent of this patent exhibits a small change in total iron concentration before and after desulfurization, indicating high stability of the desulfurization system. However, its stabilizer requires a large variety of organic components and necessitates the use of toxic and harmful substances such as morpholine. Furthermore, it is only suitable for desulfurizing agent systems with a pH of 8-10. Summary of the Invention

[0004] To address the shortcomings of existing technologies, one objective of this invention is to provide a stabilizer that can effectively improve the stability of iron ions in desulfurizers used in liquid phase redox desulfurization. A second objective is to provide a desulfurizer with excellent stability for liquid phase redox desulfurization processes. A third objective is to provide the application of the stabilizer described above in desulfurizers used in liquid phase redox desulfurization processes.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A stabilizer comprising humic acid and an alkanolamine, wherein the alkanolamine has 1 to 8 carbon atoms.

[0006] In this invention, the alcoholamine is an organic compound that simultaneously contains an amino group (-NH2, -NH-, or -N-) and a hydroxyl group (-OH).

[0007] Furthermore, the mass ratio of the alkanolamine to humic acid is 0.1-20:0.1-20.

[0008] Further, the mass ratio of the alkanolamine to humic acid is 0.5-10:0.5-15, preferably 0.8-1.5:1-5, more preferably 0.9-1.1:1-3, and even more preferably 1:1.5-2.

[0009] Furthermore, the alkanolamine has 2-7 carbon atoms, preferably 3-6, and more preferably 4-5.

[0010] Furthermore, the alkanolamine includes one or more of ethanolamine, hydroxyethyl ethylenediamine, and triisopropanolamine.

[0011] A desulfurizing agent used in a liquid-phase oxidation-reduction desulfurization process, wherein the desulfurizing agent is an aqueous solution, and the desulfurizing agent contains an iron-containing compound and a coordinating agent; the desulfurizing agent also contains a stabilizer as described above.

[0012] Furthermore, the mass ratio of the iron-containing compound to the ligand is 1:0.5-20, preferably 1:2-10, and more preferably 1:3-8.

[0013] Furthermore, the mass ratio of the iron-containing compound to the stabilizer is 1:0.5-5, preferably 1:0.8-3.

[0014] Further, the pH value of the desulfurizing agent is 8-14, preferably 9-13, and more preferably 10-12. Optionally, a pH adjuster is added during the preparation of the desulfurizing agent to adjust the pH value to the target value. Optionally, the pH adjuster is at least one selected from sodium or potassium hydroxide, sodium or potassium strong base weak acid salt, ammonia, hydrochloric acid, carbonic acid, acetic acid, nitric acid, oxalic acid, etc.

[0015] Optionally, the iron-containing compound is a water-soluble iron-containing compound.

[0016] Furthermore, the iron-containing compound includes at least one of inorganic iron-containing compounds and organic iron-containing compounds; wherein, the inorganic iron-containing compound is at least one of ferric sulfate, ferric chloride, ferric nitrate, ferrous sulfate, ferrous chloride, polyferric sulfate, polyferric chloride, ferrous nitrate, and hematite; and the organic iron-containing compound is at least one of heme iron, ferrous lactate, ferric citrate, ferrous citrate, ferrocene, and ferrophenoneline. And / or, the ligand is a water-soluble organic compound containing oxygen, nitrogen, and phosphorus with 4-20 carbon atoms, or a corresponding salt thereof, preferably at least one selected from tartaric acid, disodium tartrate, oxalic acid, disodium oxalate, citric acid, trisodium citrate, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetic acid, tetrasodium ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, sodium ethylenediaminetetramethylenephosphonate, and their polyphosphates. Further, the ligand is a water-soluble organic compound containing oxygen, nitrogen, and phosphorus with 6-18 carbon atoms, or a corresponding salt thereof; even further, it is a water-soluble organic compound containing oxygen, nitrogen, and phosphorus with 8-16 carbon atoms, or a corresponding salt thereof; and still further, it is a water-soluble organic compound containing oxygen, nitrogen, and phosphorus with 4-20 carbon atoms, or a corresponding salt thereof.

[0017] The application of the stabilizer described above in desulfurizers used in liquid phase redox desulfurization processes.

[0018] The stabilizer of this invention effectively enhances the stability of iron-containing substances in desulfurizers used in liquid-phase redox desulfurization processes in alkaline environments. The applicant explains the reasons as follows: The nitrogen atom (N) in the alkanolamine of the stabilizer can effectively form a strong Fe-N coordinate bond with the iron atom (Fe). The bond energy of this Fe-N coordinate bond is much greater than that of the Fe-O coordinate bond formed between hydroxyl (-OH) and Fe. Therefore, the stability of the Fe-N coordinate bond is greater than that of the Fe-O coordinate bond. Simultaneously, the hydroxyl group in the alkanolamine can form a Fe-O coordinate bond with iron, thereby placing Fe in the ligand structure and forming an "armor" protective layer, reducing the attack of -OH on Fe in the alkaline environment. Furthermore, humic acid, as a natural organic macromolecular mixture, contains a large number of oxygen-containing functional groups such as carbonyl, methoxy, and carboxyl groups. According to frontier orbital theory, the π antibonding orbitals of carboxyl and carbonyl groups are empty orbitals, readily accepting electrons. O* exhibits high reactivity and can act as a nucleophile or free radical to attack carbon atoms in carboxyl and carbonyl groups, undergoing addition reactions or other oxidation reactions. By introducing humic acid, the O* generated during liquid-phase redox desulfurization can be reacted away, reducing the reaction of O* with CN in the aforementioned ligand structure and maintaining the stability of the ligand structure. These multiple aspects work synergistically to effectively enhance the stability of iron-containing substances in the desulfurizing agent.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: The stabilizer of this invention can effectively enhance the stability of iron-containing substances in desulfurizers used in liquid phase oxidation-reduction desulfurization processes in alkaline environments. It can not only effectively ensure the catalytic desulfurization effect of the desulfurizer, but also help reduce the amount of iron-containing substances (catalysts) used. Attached Figure Description

[0020] Figure 1 The images show digital graphs of the desulfurizing agent from Example 1 after storage at pH=10 for 1 hour (left) and 24 hours (right).

[0021] Figure 2 The image shows the XRD pattern of the desulfurization product from Example 1.

[0022] Figure 3 The images show digital graphs of the desulfurizer from Example 2 after storage at pH=10 for 1 hour (left) and 24 hours (right).

[0023] Figure 4 The image shows the XRD pattern of the desulfurization product from Example 2.

[0024] Figure 5 The images show digital graphs of the desulfurizer from Example 3 after storage at pH=10 for 1 hour (left) and 24 hours (right).

[0025] Figure 6The image shows the XRD pattern of the desulfurization product from Example 3. Detailed Implementation

[0026] The present invention will be described in detail below with reference to embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0027] Example 1 Weigh 1 g of ferric chloride (theoretical iron content is 0.345 g) and 5 g of disodium ethylenediaminetetraacetate and add them to 150 mL of water. Stir magnetically for 10 min. After the ferric chloride and disodium ethylenediaminetetraacetate have completely dissolved, add 0.5 g of humic acid (commercially available) and 0.5 g of ethanolamine. Continue to stir magnetically for 20 min to dissolve the added humic acid and ethanolamine. Then, add water and 1 mol / L sodium carbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst (desulfurizing agent) with a pH of 10.0. The mass concentration of iron ions is 1.7046 g / L (obtained by ICP detection, the same below).

[0028] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10000 ppm was introduced into the above iron-based catalyst solution, while magnetically stirring at a rate of 1000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45 °C for 8 h to obtain the desulfurization product. The calculated desulfurization rate was 96.4%.

[0029] The desulfurization rate (w, %) is calculated according to the following formula: Where m is the mass of the desulfurization product and M is the total mass of sulfur in the mixed gas.

[0030] In addition, 50 mL of the above-mentioned iron-based catalyst aqueous solution was allowed to stand for 1-24 hours before being digitally photographed. Figure 1 As shown; 10 mg of the desulfurization product was characterized by X-ray diffraction (XRD), and the results are as follows. Figure 2 As shown.

[0031] See Figure 1The iron-based catalyst solution remained clear and showed no precipitation after standing for 24 hours at pH=10. ICP analysis showed that the iron ion concentration was still 1.7009 g / L, which is only 0.217% different from the initial concentration (1.7046 g / L). This indicates that the desulfurizer with the stabilizer of this invention has good stability.

[0032] from Figure 2 It can be seen that the XRD of the desulfurization products matches well with the standard diffraction data of the S8 (JCPDS No.08-0247) standard card, indicating that the desulfurization products are mainly elemental sulfur.

[0033] Example 2 Weigh 1 g of ferric chloride (theoretically containing 0.345 g of iron) and 5 g of disodium ethylenediaminetetraacetate and add them to 150 mL of water. Stir magnetically for 10 min. After the ferric chloride and disodium ethylenediaminetetraacetate have completely dissolved, add 0.5 g of humic acid and 0.5 g of ethanolamine. Continue to stir magnetically for 20 min to dissolve the added humic acid and ethanolamine. Then, add water and 1 mol / L sodium carbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst with a pH of 12.0 and a mass concentration of iron ions of 1.7041 g / L.

[0034] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10000 ppm was introduced into the above-mentioned iron-based catalyst solution, while magnetically stirring at a rate of 1000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45°C for 8 h to obtain the desulfurization product. The desulfurization rate was calculated to be 96.1% (calculation method is the same as in Example 1).

[0035] Take 50 mL of the above-mentioned iron-based catalyst aqueous solution, let it stand for 1-24 hours, and then take digital photos. Figure 3 As shown.

[0036] 10 mg of the desulfurization product was characterized by X-ray diffraction (XRD), and the results are as follows. Figure 4 As shown.

[0037] from Figure 3It can be seen that the aqueous solution of the iron-based catalyst remained clear and without precipitation after standing for 24 hours at pH=12. Furthermore, ICP analysis showed that the mass concentration of iron ions was 1.7003 g / L, which is a very small change (0.223%) compared to the initial concentration (1.7041 g / L). This indicates that the desulfurizer with the stabilizer of this invention has good stability.

[0038] from Figure 4 As can be seen from the data, the XRD of the desulfurization products matches well with the standard diffraction data of the S8 (JCPDS No. 08-0247) standard card, indicating that the desulfurization products are mainly elemental sulfur.

[0039] Example 3 Weigh 1 g of ferric sulfate (theoretically containing 0.28 g of iron) and 5 g of disodium ethylenediaminetetraacetate and add them to 150 mL of water. Stir magnetically for 10 min. After the ferric sulfate and disodium ethylenediaminetetraacetate have completely dissolved, add 1.0 g of humic acid and 0.5 g of hydroxyethyl ethylenediamine. Continue stirring magnetically for 20 min to dissolve the added humic acid and alkanolamine. Then, add water and 1 mol / L sodium carbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst with a pH of 14.0 and a mass concentration of iron ions of 1.3638 g / L.

[0040] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10000 ppm was introduced into the above-mentioned iron-based catalyst solution, while magnetically stirring at a rate of 1000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45°C for 8 h to obtain the desulfurization product. The calculated desulfurization rate was 96.3% (calculation method is the same as in Example 1).

[0041] Take 50 mL of the above-mentioned iron-based catalyst aqueous solution, let it stand for 1-24 hours, and then take digital photos. Figure 5 As shown.

[0042] 10 mg of the desulfurization product was characterized by X-ray diffraction (XRD), and the results are as follows. Figure 6 As shown.

[0043] from Figure 5It can be seen that the aqueous solution of the iron-based catalyst remained clear and without precipitation after standing for 24 hours at pH=14. Furthermore, ICP analysis showed that the mass concentration of iron ions was 1.3502 g / L, which is a very small change (0.997%) compared to the initial concentration (1.3638 g / L). This indicates that the desulfurizer with the stabilizer of this invention has good stability.

[0044] from Figure 6 As can be seen from the data, the XRD of the desulfurization products matches well with the standard diffraction data of the S8 (JCPDS No. 08-0247) standard card, indicating that the desulfurization products are mainly elemental sulfur.

[0045] Example 4 Weigh 1 g of ferric sulfate (theoretical iron content is 0.28 g), 1 g of ferric chloride (theoretical iron content is 0.345 g), 8 g of tetrasodium ethylenediaminetetraacetate and 2 g of trisodium limonene and add them to 150 mL of water. Stir magnetically for 10 min until completely dissolved. Then add 1.5 g of humic acid and 0.5 g of hydroxyethyl ethylenediamine and continue stirring magnetically for 20 min until all the added humic acid and alkanolamine are dissolved. Then add water and 1 mol / L sodium carbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst with a pH of 10.0 and a mass concentration of iron ions of 0.3118 g / L.

[0046] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10000 ppm was introduced into the above-mentioned iron-based catalyst solution, while magnetically stirring at a rate of 1000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45°C for 8 h to obtain the desulfurization product. The calculated desulfurization rate was 96.6% (calculation method is the same as in Example 1).

[0047] After 50 mL of the above-mentioned iron-based catalyst aqueous solution was allowed to stand for 24 h, an ICP test was performed. The result showed that the concentration of iron ions in the aqueous solution of the iron-based catalyst was 0.3101 g / L. Compared with the initial concentration (0.3118 g / L), the change in the mass concentration of iron ions was extremely small (0.545%), indicating that the desulfurizer with the stabilizer of the present invention has good stability.

[0048] Example 5 Weigh 1 g of ferric sulfate (theoretical iron content is 0.28 g), 1 g of ferric nitrate (theoretical iron content is 0.228 g), 4 g of tetrasodium ethylenediaminetetraacetate, and 4 g of sodium citrate and add them to 150 mL of water. Stir magnetically for 10 min until completely dissolved. Then add 1.5 g of humic acid and 0.5 g of triisopropanolamine and continue stirring magnetically for 20 min until the added humic acid and triisopropanolamine are completely dissolved. Then add water and 1 mol / L sodium bicarbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst with a pH of 12.0 and a mass concentration of iron ions of 0.2518 g / L.

[0049] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10,000 ppm was introduced into the above-mentioned iron-based catalyst solution, while magnetically stirring at a rate of 1,000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45°C for 8 h to obtain the desulfurization product. The calculated desulfurization rate was 96.4% (calculated in the same way as in Example 1).

[0050] After 50 mL of the above-mentioned iron-based catalyst aqueous solution was allowed to stand for 24 h, an ICP test was performed. The result showed that the concentration of iron ions in the aqueous solution of the iron-based catalyst was 0.2509 g / L. Compared with the initial concentration (0.2518 g / L), the change in the mass concentration of iron ions was extremely small (0.357%), indicating that the desulfurizer with the stabilizer of the present invention has good stability.

[0051] Example 6 Weigh 1 g of ferric sulfate (theoretical iron content is 0.28 g), 1 g of ferrocene (theoretical iron content is 0.301 g), and 5 g of tetrasodium ethylenediaminetetraacetate and add them to 150 mL of water. Stir magnetically for 10 min until completely dissolved. Then add 1.5 g of humic acid and 0.5 g of triisopropanolamine and continue stirring magnetically for 20 min until the added humic acid and triisopropanolamine are completely dissolved. Then add water and 1 mol / L sodium bicarbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst with a pH of 10.0 and a mass concentration of iron ions of 0.2863 g / L.

[0052] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10,000 ppm was introduced into the above-mentioned iron-based catalyst solution, while magnetically stirring at a rate of 1,000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45°C for 8 h to obtain the desulfurization product. The calculated desulfurization rate was 96.3% (calculation method is the same as in Example 1).

[0053] After 50 mL of the above-mentioned iron-based catalyst aqueous solution was allowed to stand for 24 h, an ICP test was performed. The result showed that the concentration of iron ions in the aqueous solution of the iron-based catalyst was 0.2846 g / L. Compared with the initial concentration (0.2863 g / L), the change in the mass concentration of iron ions was extremely small (0.594%), indicating that the desulfurizer with the stabilizer of the present invention has good stability.

[0054] Comparative Example 1 Weigh 1 g of ferric sulfate (theoretically containing 0.28 g of iron) and 5 g of tetrasodium ethylenediaminetetraacetate and add them to 150 mL of water. Stir magnetically for 10 min until completely dissolved. Then add 1.5 g of humic acid and continue stirring magnetically for 20 min until the added humic acid is completely dissolved. Then add water and 1 mol / L sodium bicarbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst with a pH of 12.0 and a mass concentration of iron ions of 0.1247 g / L.

[0055] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10000 ppm was introduced into the above iron-based catalyst solution, while magnetically stirring at a rate of 1000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45°C for 8 h to obtain the desulfurization product. The desulfurization rate was calculated to be 82.3% (calculation method is the same as in Example 1).

[0056] After 50 mL of the above-mentioned iron-based catalyst aqueous solution was allowed to stand for 24 h, an ICP test was performed. The results showed that the concentration of iron ions in the aqueous solution of the iron-based catalyst was 0.1107 g / L. The mass concentration of iron ions changed by 11.227% before and after standing.

[0057] Comparative Example 2 Weigh 1 g of ferric sulfate (theoretically containing 0.28 g of iron) and 5 g of tetrasodium ethylenediaminetetraacetate and add them to 150 mL of water. Stir magnetically for 10 min until completely dissolved. Then, add water and 1 mol / L sodium bicarbonate solution to the solution and bring the volume to 200 mL to obtain an aqueous solution of iron-based catalyst with a pH of 12.0 and a mass concentration of iron ions of 0.1233 g / L.

[0058] Using H2S as the sulfur source for desulfurization, a mixed gas (composed of H2S and N2) with a H2S concentration of 10000 ppm was introduced into the above iron-based catalyst solution, while magnetically stirring at a rate of 1000 rpm for 6 h. After the reaction was completed, the solution was separated by centrifugation, and the precipitate and filtrate were collected. The precipitate was washed three times with water and anhydrous ethanol in sequence, and then vacuum dried at 45°C for 8 h to obtain the desulfurization product. The desulfurization rate was calculated to be 60.3% (calculation method is the same as in Example 1).

[0059] After 50 mL of the above-mentioned iron-based catalyst aqueous solution was allowed to stand for 24 hours, an ICP test was performed. The results showed that the concentration of iron ions in the aqueous solution of the iron-based catalyst was 0.0849 g / L. The mass concentration of iron ions changed by 31.43% before and after standing.

[0060] Comparative Example 3 Example 1 was repeated, except that the amount of humic acid and alkanolamine added was 0.

[0061] As a result, the desulfurization rate was 54.3%.

[0062] The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7044 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.0511 g / L.

[0063] Comparative Example 4 Example 1 was repeated, except that the amount of humic acid added was 1g and the amount of alcoholamine added was 0g.

[0064] As a result, the desulfurization rate was 70.6%. The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.4106 g / L. Comparative Example 5 Example 1 was repeated, except that the amount of humic acid added was 0 and the amount of alcoholamine added was 1g.

[0065] As a result, the desulfurization rate was 80.2%. The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.5573 g / L. Comparative Example 6 Repeat Example 1, except that the alcohol amine is 9-amino-1-nonanol (an alcohol amine with 9 carbon atoms). As a result, the desulfurization rate was 54.6%. The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.0766 g / L.

[0066] Comparative Example 7 Repeat Example 1, except that the alcohol amine is 10-amino-1-decanol (an alcohol amine with 10 carbon atoms).

[0067] As a result, the desulfurization rate was 54.3%.

[0068] The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.0518 g / L.

[0069] Comparative Example 8 Example 1 was repeated, except that a mixture of ethylene glycol and ethylenediamine was used instead of ethanolamine, wherein the molar ratio of ethylene glycol to ethylenediamine was 1:1.

[0070] As a result, the desulfurization rate was 54.2%.

[0071] The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.0472 g / L.

[0072] Comparative Example 9 Example 1 was repeated, except that the total amount of humic acid and alkanolamine added was 1g, and the mass ratio of humic acid to alkanolamine was 0.5:1.

[0073] As a result, the desulfurization rate was 84.5%. The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.5521 g / L.

[0074] Example 7 Example 1 was repeated, except that the total amount of humic acid and alcoholic amine added was 1g, and the mass ratio of humic acid to alcoholic amine was 3:1.

[0075] As a result, the desulfurization rate was 88.3%.

[0076] The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.5318 g / L. Comparative Example 10 Example 1 was repeated, except that the total amount of humic acid and alkanolamine added was 1g, and the mass ratio of humic acid to alkanolamine was 3.5:1.

[0077] As a result, the desulfurization rate was 70.5%.

[0078] The initial mass concentration of iron ions in 50 mL of the above-mentioned iron-based catalyst aqueous solution was 1.7046 g / L. After standing for 24 h, ICP test was performed, and the concentration of iron ions in the aqueous solution of the iron-based catalyst was 1.5216 g / L.

[0079] It is evident that controlling the ratio of humic acid to alkanolamine within a specific range helps to achieve particularly excellent desulfurization results. This may be because, within a specific range, iron-containing substances are more stable in solution and can sustainably exert good catalytic desulfurization effects.

[0080] Example 8 The filtrate obtained from the final filtration in Example 1 was re-introduced with mixed gas and desulfurized again. The desulfurization rate was calculated to be 96.4%, and the mass concentration of iron ions in the filtrate after the second desulfurization was still 1.6981 g / L.

[0081] Then, the filtrate obtained after the second desulfurization was re-introduced with mixed gas for further desulfurization. The calculated desulfurization rate was 96.3%, and the iron ion concentration in the filtrate remained at 1.6916 g / L. The above-mentioned continuous repeatability experiments further demonstrate that the stabilizer of the present invention has excellent stabilizing ability for iron-containing substances.

[0082] The above embodiments should be understood as being used only to illustrate the present invention more clearly, and not to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art fall within the scope defined by the appended claims.

Claims

1. A stabilizer, characterized in that, It includes humic acid and alkanolamine, wherein the alkanolamine has 1 to 8 carbon atoms.

2. The stabilizer according to claim 1, characterized in that, The mass ratio of the alkanolamine to humic acid is 0.1-20:0.1-20.

3. The stabilizer according to claim 2, characterized in that, The mass ratio of the alkanolamine to humic acid is 0.5-10:0.5-15, preferably 0.8-1.5:1-5.

4. The stabilizer according to any one of claims 1-3, characterized in that, The alkanolamine has 2-7 carbon atoms, preferably 3-6.

5. The stabilizer according to any one of claims 1-3, characterized in that, The alkanolamine includes one or more of ethanolamine, hydroxyethyl ethylenediamine, and triisopropanolamine.

6. A desulfurizing agent for use in a liquid-phase oxidation-reduction desulfurization process, wherein the desulfurizing agent is an aqueous solution, and the desulfurizing agent contains an iron-containing compound and a coordinating agent; characterized in that, The desulfurizing agent further contains the stabilizer as described in any one of claims 1-5.

7. The desulfurizing agent according to claim 6, characterized in that, The mass ratio of the iron-containing compound to the ligand is 1:0.5-20, preferably 1:2-10, and more preferably 1:3-8.

8. The desulfurizing agent according to claim 6, characterized in that, The mass ratio of the iron-containing compound to the stabilizer is 1:0.5-5, preferably 1:0.8-3; and / or the pH value of the desulfurizing agent is 8-14, preferably 9-13, and more preferably 10-12.

9. The desulfurizing agent according to claim 6, characterized in that, Iron-containing compounds include at least one of inorganic iron-containing compounds and organic iron-containing compounds; wherein, the inorganic iron-containing compounds are at least one of ferric sulfate, ferric chloride, ferric nitrate, ferrous sulfate, ferrous chloride, polyferric sulfate, polyferric chloride, ferrous nitrate, and hematite; and the organic iron-containing compounds are at least one of heme iron, ferrous lactate, ferrous citrate, ferrous citrate, ferrocene, and ferrophenonelin. And / or, the ligand is a water-soluble organic compound containing oxygen, nitrogen, and phosphorus with 4-20 carbon atoms or its corresponding salt, preferably at least one of tartaric acid, disodium tartrate, oxalic acid, disodium oxalate, citric acid, trisodium citrate, ethylenediaminetetraacetic acid, disodium ethylenediaminetetraacetic acid, tetrasodium ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, sodium ethylenediaminetetramethylenephosphonate, and their polyphosphates.

10. The use of the stabilizer as described in any one of claims 1-5 in a desulfurizing agent used in a liquid-phase oxidation-reduction desulfurization process.

Images