A method for separating and extracting vanadium from a high-acidity vanadium-containing solution

Abstract

The present invention relates to a method for separating and extracting vanadium from a high-acidity vanadium-containing solution. The technical solution is as follows: First, the high-acidity vanadium-containing solution is simultaneously introduced into n first ion exchange columns of the first part of the ion exchange column, and then sequentially flows through the second ion exchange column 1, the second ion exchange column 2,..., the second ion exchange column m of the second part of the ion exchange column; when the vanadium concentration in the adsorption residual liquid flowing out of the second ion exchange column m is 3-5% of the vanadium concentration in the high-acidity vanadium-containing solution, the inflow of the high-acidity vanadium-containing solution is stopped to obtain the loaded resin. Then, deionized water is sequentially flowed through the second part of the ion exchange column in a countercurrent manner, and then simultaneously flowed into the first part of the ion exchange column in a countercurrent manner for washing; then, the desorbent is sequentially flowed through the second part of the ion exchange column in a countercurrent manner, and then flowed into the first part of the ion exchange column in a countercurrent manner for desorption respectively to obtain the desorbed resin and the vanadium-rich solution. The process of the present invention is short, environmentally friendly, and has good vanadium-iron separation effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of separating and extracting vanadium from vanadium-containing solutions. Specifically, it relates to a method for separating and extracting vanadium from high-acidity vanadium-containing solutions. Background Art

[0002] The acid leaching solution of shale vanadium extraction has the characteristics of low pH and many impurity ions, and is a complex vanadium-containing solution with high acidity. Industrially, amine anion exchange resins are mostly used as adsorption resins, and the ion exchange method is used to purify and enrich the acid leaching solution of shale vanadium extraction. When extracting vanadium from a vanadium-containing solution using an anion resin, it is usually necessary to adjust the pH of the solution to above 1.8, and make vanadium exist in the form of polyvanadate anions by adjusting the potential, and then realize the adsorption of vanadium. During the pH adjustment process, a large amount of alkali is consumed, and a large amount of neutralization slag containing harmful metal ions and difficult to treat is generated during this process. In addition, due to the large amount of impurity ions in the acid leaching solution, iron ions are extremely easy to co-adsorb with vanadium and are difficult to separate from vanadium.

[0003] The patented technology of "A Method for Improving the Vanadium Adsorption Rate from Acidic Solutions" (CN 114279806A) forms a cyclic treatment mechanism by performing one-stage two-stage series adsorption, two-stage four-stage series adsorption, two-stage series water washing, three-stage series reverse desorption, two-stage series water washing, two-stage series acid transformation, two-stage series water washing, and two-stage adsorption on the acidic solution respectively, changing the traditional extraction form. Although a relatively high adsorption efficiency is obtained, it is necessary to first add ammonium bicarbonate to the leaching solution after acid mixing and ripening to neutralize and adjust the pH of the solution to 2.0, which causes a large amount of alkali consumption in this process.

[0004] The patented technology of "A Method for Extracting Vanadium by Ion Exchange from High-Iron Low-Vanadium Solutions" (CN 114959308A) adds a neutralizing agent to the high-iron low-vanadium solution for neutralization, and adjusts the pH of the solution to 1.8 - 1.9. A large amount of difficult-to-treat neutralization slag is generated during this process, which is not environmentally friendly; and this method still synchronously adsorbs iron and vanadium ions and cannot achieve the synchronous separation of vanadium and iron, and it is necessary to use sulfuric acid or hydrochloric acid to pickle the resin, increasing the complexity of the process and the cost of reagents.

[0005] The patented technology of "A Method for Purifying and Enriching Vanadium from Vanadium-Containing Solutions" (CN 110241306 B) uses a chelating resin to adsorb the vanadium-containing solution, uses sodium hydroxide for segmented desorption of the resin, and uses oxalic acid for regeneration of the resin. However, this technology needs to adjust the pH of the vanadium-containing solution to 1.4 - 2.6, which causes a large amount of alkali consumption. And during segmented desorption, iron ions will also be enriched, and the later-stage desorption solution rich in iron cannot be treated, which is not conducive to environmental protection.

[0006] In summary, when the existing ion exchange process is used to treat vanadium-containing solutions, there are problems such as a long process, the need to adjust the pH, resulting in a large amount of alkali consumption, being unfavorable to environmental protection, and difficulty in separating vanadium from typical impurities such as iron. Summary of the Invention

[0007] The present invention aims to overcome the defects of the prior art and aims to provide a method for separating and extracting vanadium from high-acidity vanadium-containing solutions with a short process and environmental friendliness, and the method can achieve good separation effect between vanadium and impurity iron.

[0008] To achieve the above object, the system for separating and extracting vanadium of the present invention is carried out according to Step 1 and Step 2.

[0009] The system for separating and extracting vanadium is composed of two parts of ion exchange columns. The first part of ion exchange columns is composed of n first ion exchange columns connected in parallel, and the second part of ion exchange columns is composed of m second ion exchange columns connected in series; where: n is any natural number among 2, 3, 4, and m is any natural number among 2, 3, ……, 7, 8.

[0010] Step 1. Resin adsorption

[0011] The method of resin adsorption is to simultaneously flow the high-acidity vanadium-containing solution into the first ion exchange column 1, the first ion exchange column 2, ……, the first ion exchange column n of the first part of ion exchange columns at a flow rate of 1 - 1.5 BV / h; the preliminarily adsorbed high-acidity vanadium-containing solution flowing out of the first part of ion exchange columns then flows through the second ion exchange column 1, the second ion exchange column 2, ……, the second ion exchange column m of the second part of ion exchange columns in turn at a flow rate n times that of 1 - 1.5 BV / h. When the vanadium concentration of the adsorption residual liquid flowing out of the second ion exchange column m is 3 - 5% of the vanadium concentration in the high-acidity vanadium-containing solution, stop flowing in the high-acidity vanadium-containing solution to obtain the loaded resin and the adsorption residual liquid.

[0012] The high-acidity vanadium-containing solution: pH is 0 - 1; V(V) concentration < 4.5 g / L; Fe(III) concentration < 8 g / L.

[0013] The resin filled in the first part of ion exchange columns is the "modified resin for extracting vanadium from high-acidity vanadium-containing solutions", and the volume of the resin filled in the first part of ion exchange columns is 1 BV, 1 BV = 0.20 - 3.53 m 3 ; the resin filled in the second part of ion exchange columns is the same as the resin filled in the first part of ion exchange columns, and the volume of the resin filled in the second part of ion exchange columns is 2 BV.

[0014] The preparation method of the modified resin for extracting vanadium from a high-acidity vanadium-containing solution comprises the following steps: preparing ingredients according to a solid-liquid ratio of aminophosphoric acid-type chelating resin to ethanol of 1:(5-10) kg / L, mixing to obtain a mixture, then ultrasonically dispersing the mixture for 5-15 minutes, and performing solid-liquid separation to obtain a resin to be treated and a pretreatment liquid; adding aminosulfonic acid at a uniform speed to the resin to be treated at a temperature of 40-80°C and a rotation speed of 240-400 r / min, wherein the volume of the aminosulfonic acid added is 5-8 times the volume of the resin to be treated; continuing stirring for 20-36 hours, and performing solid-liquid separation to obtain a modified residual liquid and a treated resin; and allowing the treated resin to stand for 24-36 hours and washing with deionized water until the pH of the washing liquid is 6-7, thereby obtaining the modified resin for extracting vanadium from a high-acidity vanadium-containing solution.

[0015] The functional group of the aminophosphoric acid type chelating resin is -CH2NHCH2PO3 2- .

[0016] The power of the ultrasonic wave is 60-120W.

[0017] Step 2: Resin desorption

[0018] The resin desorption method is to first countercurrently flow 10 to 40 BV of deionized water through the second ion exchange column m, the second ion exchange column m-1, ..., the second ion exchange column 1 at a flow rate of 3 to 5 BV / h, and then countercurrently flow the first section of washing wastewater flowing out of the second ion exchange column 1 into n first ion exchange columns at a flow rate of 1 / n times 3 to 5 BV / h for washing, thereby obtaining the resin to be desorbed and the second section of washing wastewater.

[0019] Then, 5 to 20 BV of the desorbent is countercurrently passed through the second ion exchange column m, the second ion exchange column m-1, ..., the second ion exchange column 1 at a flow rate of 0.2 to 0.5 BV / h. The desorbent flowing out of the second ion exchange column 1 is countercurrently passed through n first ion exchange columns at a flow rate of 1 / n times 0.2 to 0.5 BV / h for desorption to obtain desorbed resin and vanadium-rich solution.

[0020] The desorbent is a mixed solution of NaOH solution and NaCl solution, the molar ratio of NaOH solution:NaCl solution is (5-8):1; the concentration of the NaOH solution is 3-6 mol / L, and the concentration of the NaCl solution is 0.6-0.75 mol / L.

[0021] The n first ion exchange columns are identical. The diameter of each first ion exchange column is 0.5 - 1.5 m, and the ratio of the height to the diameter of each first ion exchange column is (1 - 2):1; the m second ion exchange columns are identical. The diameter of each second ion exchange column is 0.5 - 1.5 m, and the ratio of the height to the diameter of each second ion exchange column is (2 - 4):1.

[0022] The concentration of the sulfamic acid is 0.2 - 0.85 mol / L.

[0023] Due to the adoption of the above technical solution, the present invention has the following positive effects compared with the prior art:

[0024] 1. The present invention uses the reaction of sulfamic acid with an amino-phosphoric acid type chelating resin for modification. During the reaction, the sulfamic acid contacts with the amino-phosphoric acid type chelating resin, destroying the -NH bond on the resin, causing the H connected to -N to be removed, forming a sulfonamide group, and obtaining a modified resin for extracting vanadium from a high-acidity vanadium-containing solution (hereinafter referred to as "modified resin"). There is no volatilization of toxic substances during the modification process. The modifier has no odor and low toxicity to the human body, and is environmentally friendly; the present invention directly uses a high-acidity vanadium-containing solution as the adsorption stock solution, reducing the process of adjusting the pH with alkaline agents such as sodium hydroxide and calcium hydroxide, and no neutralization slag is generated, which is beneficial to environmental protection.

[0025] 2. The resin filled in the first ion exchange column and the second ion exchange column in the present invention is a modified resin, and the modified resin can extract vanadium from a high-acidity vanadium-containing solution with a pH of 0 - 1. Under high-acidity conditions, the existence form of vanadium in the solution is VO2 + , and the modified resin is easy to chelate with VO2 + under acidic conditions, and has higher selectivity for vanadium. In addition, the phosphoric acid group on the modified resin is a strong acidic cation group, which can carry out cation exchange with VO2 + in the solution. The modification changes the property of the functional group amino (-NH) of the amino-phosphoric acid type chelating resin, greatly reducing the chelating effect between the modified resin and iron in the solution, and strengthening the separation effect of vanadium and impurity iron.

[0026] 3. The present invention purifies and enriches the high-acidity vanadium-containing solution by using a first part of an ion exchange column and a second part of an ion exchange column. The first part of the ion exchange column is in parallel connection, and preliminarily adsorbs vanadium in the high-acidity vanadium-containing solution at a flow rate of 1-1.5 BV / h; the second part of the ion exchange column is in series connection, and re-adsorbs the high-acidity vanadium-containing solution flowing out of the first part of the ion exchange column at a flow rate n times that when flowing into the first ion exchange column. Through multi-stage adsorption, the adsorption rate of vanadium is >99%. The adsorption law of the modified resin for vanadium is to adsorb rapidly first, and then slowly adsorb until adsorption equilibrium. Therefore, the present invention sets up two parts of ion exchange columns for adsorption. The adsorption flow rate of the first part of the ion exchange column is slow, so that the modified resin and vanadium have sufficient contact time; the adsorption flow rate of the second part of the ion exchange column is relatively fast, and the number of stages increases, so that the modified resin has sufficient adsorption sites for vanadium adsorption, so the adsorption rate of vanadium >99% is achieved.

[0027] "4. The present invention uses a mixed solution of sodium hydroxide and sodium chloride to desorb the resin to be desorbed. Sodium hydroxide is an alkaline desorbing agent. When flowing through the resin to be desorbed in the first and second parts of the ion exchange column, it changes the pH environment of the resin to be desorbed, so that the vanadium on the resin to be desorbed changes from the VO2 + cation form to the vanadate anion form and is thus desorbed into the vanadium-rich solution, achieving a vanadium desorption rate >98%. The iron content in the vanadium-rich solution is less than 0.12 g / L, and the vanadium-iron separation effect is good; the concentration of V2O5 in the vanadium-rich solution is 23-30 g / L, and the vanadium enrichment effect is good.

[0028] Therefore, the present invention has the characteristics of a short process and environmental friendliness, and the separation effect of vanadium and impurity iron is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a resin adsorption system of the system for separating and extracting vanadium of the present invention;

[0030] Figure 2 is a resin desorption system of the system for separating and extracting vanadium of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0031] The following further describes the present invention in conjunction with the drawings and specific embodiments, and it is not intended to limit the scope of its protection.

[0032] A method for separating and extracting vanadium from a high-acidity vanadium-containing solution. The method for separating and extracting vanadium described in this specific embodiment is to use the system for separating and extracting vanadium to carry out according to the following Step 1 and Step 2:

[0033] The system for separating and extracting vanadium is as Figure 1 and Figure 2As shown, it consists of two parts of ion exchange columns. The first part of the ion exchange column is composed of n first ion exchange columns connected in parallel, and the second part of the ion exchange column is composed of m second ion exchange columns connected in series; where: n is any natural number among 2, 3, and 4, and m is any natural number among 2, 3, ……, 7, and 8.

[0034] Step 1: Resin adsorption

[0035] The method of resin adsorption is to simultaneously flow the high-acidity vanadium-containing solution into the first ion exchange column 1, the first ion exchange column 2, ……, the first ion exchange column n of the first part of the ion exchange column at a flow rate of 1 - 1.5 BV / h; the preliminarily adsorbed high-acidity vanadium-containing solution flowing out of the first part of the ion exchange column then flows through the second ion exchange column 1, the second ion exchange column 2, ……, the second ion exchange column m of the second part of the ion exchange column in turn at a flow rate n times that of 1 - 1.5 BV / h. When the vanadium concentration of the adsorption residual liquid flowing out of the second ion exchange column m is 3 - 5% of the vanadium concentration in the high-acidity vanadium-containing solution, stop flowing in the high-acidity vanadium-containing solution to obtain the loaded resin and the adsorption residual liquid.

[0036] The high-acidity vanadium-containing solution: pH is 0 - 1; V(V) concentration < 4.5 g / L; Fe(III) concentration < 8 g / L.

[0037] The resin filled in the first part of the ion exchange column is the "modified resin for extracting vanadium from high-acidity vanadium-containing solution", and the volume of the resin filled in the first part of the ion exchange column is 1 BV, 1 BV = 0.20 - 3.53 m 3 ; The resin filled in the second part of the ion exchange column is the same as the resin filled in the first part of the ion exchange column, and the volume of the resin filled in the second part of the ion exchange column is 2 BV.

[0038] The preparation method of the "modified resin for extracting vanadium from high-acidity vanadium-containing solution" is: proportion the amino-phosphoric acid type chelating resin and ethanol according to a solid-liquid ratio of 1:(5 - 10) Kg / L, mix to obtain a mixed material, then ultrasonically disperse the mixed material for 5 - 15 min, perform solid-liquid separation to obtain the resin to be treated and the pretreatment liquid; under the conditions of a temperature of 40 - 80 °C and a rotation speed of 240 - 400 r / min, uniformly add aminosulfonic acid to the resin to be treated, and the volume of the added aminosulfonic acid is 5 - 8 times the volume of the resin to be treated; then continue to stir for 20 - 36 h, perform solid-liquid separation to obtain the modified residual liquid and the treated resin; let the treated resin stand for 24 - 36 h, and wash it with deionized water until the pH of the washing liquid is 6 - 7 to prepare the modified resin for extracting vanadium from high-acidity vanadium-containing solution.

[0039] The power of the ultrasonic wave is 60 - 120 W.

[0040] Step 2: Resin desorption

[0041] The resin desorption method is as follows: First, 10 - 40 BV of deionized water flows countercurrently through the second ion exchange column m, the second ion exchange column m - 1, ……, the second ion exchange column 1 in sequence at a flow rate of 3 - 5 BV / h. The first-stage washing wastewater flowing out from the second ion exchange column 1 then flows countercurrently into n first ion exchange columns for washing at a flow rate of 1 / n times 3 - 5 BV / h respectively, to obtain the resin to be desorbed and the second-stage washing wastewater; then, 5 - 20 BV of desorbent flows countercurrently through the second ion exchange column m, the second ion exchange column m - 1, ……, the second ion exchange column 1 in sequence at a flow rate of 0.2 - 0.5 BV / h. The desorbing solution flowing out from the second ion exchange column 1 then flows countercurrently into n first ion exchange columns for desorption at a flow rate of 1 / n times 0.2 - 0.5 BV / h respectively, to obtain the desorbed resin and the vanadium-rich solution.

[0042] The desorbent is a mixed solution of NaOH solution and NaCl solution, and the molar ratio of NaOH solution:NaCl solution is (5 - 8):1; the concentration of the NaOH solution is 3 - 6 mol / L, and the concentration of the NaCl solution is 0.6 - 0.75 mol / L.

[0043] The n first ion exchange columns are the same, the diameter of each first ion exchange column is 0.5 - 1.5 m, and the ratio of the height to the diameter of each first ion exchange column is (1 - 2):1; the m second ion exchange columns are the same, the diameter of each second ion exchange column is 0.5 - 1.5 m, and the ratio of the height to the diameter of each second ion exchange column is (2 - 4):1.

[0044] The concentration of the sulfamic acid is 0.2 - 0.85 mol / L.

[0045] In this specific embodiment:

[0046] The functional group of the amino phosphoric acid type chelating resin is -CH2NHCH2PO3 2- 。

[0047] Details are not repeated in the examples.

[0048] Example 1

[0049] A method for separating and extracting vanadium from a high-acidity vanadium-containing solution. The method for separating and extracting vanadium in this example is to carry out according to the following Step 1 and Step 2 by using a system for separating and extracting vanadium:

[0050] The system for separating and extracting vanadium is as Figure 1 and Figure 2As shown, it consists of two parts of ion exchange columns. The first part of the ion exchange column is composed of n first ion exchange columns connected in parallel, and the second part of the ion exchange column is composed of m second ion exchange columns connected in series; in this embodiment: n=2, m=3.

[0051] Step 1: Resin adsorption

[0052] The resin adsorption method comprises the following steps: simultaneously flowing a high-acidity vanadium-containing solution through a first ion exchange column 1 and a first ion exchange column 2 of a first ion exchange column at a flow rate of 1.5 BV / h. The preliminarily adsorbed high-acidity vanadium-containing solution flowing out of the first ion exchange column then flows through a second ion exchange column 1 and a second ion exchange column 2 of a second ion exchange column at a flow rate twice that of 1.5 BV / h. When the vanadium concentration of the adsorption residual solution flowing out of the second ion exchange column 2 reaches 3% of the vanadium concentration in the high-acidity vanadium-containing solution, the flow of the high-acidity vanadium-containing solution is stopped, thereby obtaining a loaded resin and an adsorption residual solution.

[0053] The high-acidity vanadium-containing solution has a pH of 0, a V(V) concentration of 1.2 g / L, and a Fe(III) concentration of 1 g / L.

[0054] The resin filled in the first part of the ion exchange column is "modified resin for extracting vanadium from high-acidity vanadium-containing solution", and the volume of the resin filled in the first part of the ion exchange column is 1BV, 1BV = 0.20m 3 The resin filled in the second part of the ion exchange column is the same as the resin filled in the first part of the ion exchange column, and the volume of the resin filled in the second part of the ion exchange column is 2BV.

[0055] The preparation method of the "modified resin for extracting vanadium from a high-acidity vanadium-containing solution" is as follows: ingredients are prepared according to a solid-liquid ratio of aminophosphoric acid-type chelating resin to ethanol of 1:5 kg / L, mixed to obtain a mixture, and then ultrasonically disperse the mixture for 5 minutes, solid-liquid separation, to obtain a resin to be treated and a pretreatment liquid; aminosulfonic acid is uniformly added to the resin to be treated at a temperature of 40°C and a rotation speed of 240 r / min, the volume of the added aminosulfonic acid being 5 times the volume of the resin to be treated; stirring is continued for 20 hours, solid-liquid separation is carried out, to obtain a modified residual liquid and a treated resin; the treated resin is allowed to stand for 24 hours, and washed with deionized water until the pH of the washing liquid reaches 6, to obtain a modified resin for extracting vanadium from a high-acidity vanadium-containing solution.

[0056] The power of the ultrasonic wave is 60W.

[0057] Step 2: Resin desorption

[0058] The resin desorption method is as follows: First, 10 BV of deionized water flows countercurrently through the second ion exchange column 2 and the second ion exchange column 1 in sequence at a flow rate of 5 BV / h. The first-stage washing wastewater flowing out from the second ion exchange column 1 then flows countercurrently into 2 first ion exchange columns for washing at a flow rate of 1 / 2 times 5 BV / h, obtaining the resin to be desorbed and the second-stage washing wastewater; then, 5 BV of desorbent flows countercurrently through the second ion exchange column 2 and the second ion exchange column 1 in sequence at a flow rate of 0.5 BV / h. The desorbate flowing out from the second ion exchange column 1 then flows countercurrently into 2 first ion exchange columns for desorption at a flow rate of 1 / 2 times 0.5 BV / h, obtaining the desorbed resin and the vanadium-rich solution.

[0059] The desorbent is a mixed solution of NaOH solution and NaCl solution, and the molar ratio of NaOH solution to NaCl solution is 5:1; the concentration of the NaOH solution is 3 mol / L, and the concentration of the NaCl solution is 0.6 mol / L.

[0060] The 2 first ion exchange columns are the same. The diameter of each first ion exchange column is 0.5 m, and the ratio of the height to the diameter of each first ion exchange column is 1:1; the 2 second ion exchange columns are the same. The diameter of each second ion exchange column is 0.5 m, and the ratio of the height to the diameter of each second ion exchange column is 2:1.

[0061] The concentration of the sulfamic acid is 0.2 mol / L.

[0062] In this example: The adsorption rate of V in the high-acidity vanadium-containing solution is 99.33%; the desorption rate of V is 98.55%; the concentration of V2O5 in the vanadium-rich solution is 25.55 g / L; the concentration of Fe is 0.11 g / L.

[0063] Example 2

[0064] A method for separating and extracting vanadium from a high-acidity vanadium-containing solution. The method for separating and extracting vanadium in this example is carried out according to the following step 1 and step 2 by using a system for separating and extracting vanadium:

[0065] As Figure 1 and Figure 2 shown, the system for separating and extracting vanadium is composed of two parts of ion exchange columns. The first part of the ion exchange column is composed of n first ion exchange columns connected in parallel, and the second part of the ion exchange column is composed of m second ion exchange columns connected in series; in this example: n = 3; m = 4.

[0066] Step 1. Resin adsorption

[0067] The resin adsorption method comprises the following steps: simultaneously flowing a high-acidity vanadium-containing solution into a first ion exchange column 1, a first ion exchange column 2, and a first ion exchange column 3 of a first part of the ion exchange column at a flow rate of 1.25 BV / h; the preliminarily adsorbed high-acidity vanadium-containing solution flowing out of the first part of the ion exchange column then flows through a second ion exchange column 1, a second ion exchange column 2, and a second ion exchange column 4 of a second part of the ion exchange column at a flow rate three times that of 1.25 BV / h; and when the vanadium concentration of the adsorption residual solution flowing out of the second ion exchange column 4 reaches 4% of the vanadium concentration in the high-acidity vanadium-containing solution, stopping the flow of the high-acidity vanadium-containing solution to obtain a loaded resin and an adsorption residual solution.

[0068] The high-acidity vanadium-containing solution has a pH of 0.4, a V(V) concentration of 2.5 g / L, and a Fe(III) concentration of 4.5 g / L.

[0069] The resin filled in the first part of the ion exchange column is "modified resin for extracting vanadium from high-acidity vanadium-containing solution", and the volume of the resin filled in the first part of the ion exchange column is 1BV, 1BV = 2.00m 3 The resin filled in the second part of the ion exchange column is the same as the resin filled in the first part of the ion exchange column, and the volume of the resin filled in the second part of the ion exchange column is 2BV.

[0070] The preparation method of the "modified resin for extracting vanadium from a high-acidity vanadium-containing solution" is as follows: ingredients are prepared according to a solid-liquid ratio of aminophosphoric acid-type chelating resin to ethanol of 1:7 kg / L, mixed to obtain a mixture, and then ultrasonically disperse the mixture for 10 minutes, solid-liquid separation, to obtain a resin to be treated and a pretreatment liquid; aminosulfonic acid is uniformly added to the resin to be treated at a temperature of 60°C and a rotation speed of 320 r / min, with the volume of the aminosulfonic acid added being 6 times the volume of the resin to be treated; stirring is continued for 28 hours, solid-liquid separation is carried out, to obtain a modified residual liquid and a treated resin; the treated resin is allowed to stand for 30 hours, and washed with deionized water until the pH of the washing liquid reaches 6.5, to obtain a modified resin for extracting vanadium from a high-acidity vanadium-containing solution.

[0071] The power of the ultrasonic wave is 90W.

[0072] Step 2: Resin desorption

[0073] The resin desorption method is as follows: First, 25 BV of deionized water flows countercurrently through the second ion exchange column 4, the second ion exchange column 3,..., the second ion exchange column 1 at a flow rate of 4 BV / h in sequence. The first-stage washing wastewater flowing out from the second ion exchange column 1 then flows countercurrently into 3 first ion exchange columns for washing at a flow rate of 1 / 3 times 4 BV / h, obtaining the resin to be desorbed and the second-stage washing wastewater; then, 12 BV of desorbent flows countercurrently through the second ion exchange column 4, the second ion exchange column 3,..., the second ion exchange column 1 at a flow rate of 0.3 BV / h in sequence. The desorbing solution flowing out from the second ion exchange column 1 then flows countercurrently into 3 first ion exchange columns for desorption at a flow rate of 1 / 3 times 0.3 BV / h, obtaining the desorbed resin and the vanadium-rich solution.

[0074] The desorbent is a mixed solution of NaOH solution and NaCl solution, and the molar ratio of NaOH solution to NaCl solution is 7:1; the concentration of the NaOH solution is 4.5 mol / L, and the concentration of the NaCl solution is 0.64 mol / L.

[0075] The 3 first ion exchange columns are the same. The diameter of each first ion exchange column is 1 m, and the ratio of the height to the diameter of each first ion exchange column is 1.5:1; the 4 second ion exchange columns are the same. The diameter of each second ion exchange column is 1 m, and the ratio of the height to the diameter of each second ion exchange column is 3:1.

[0076] The concentration of the sulfamic acid is 0.55 mol / L.

[0077] In this example: The adsorption rate of V in the high-acidity vanadium-containing solution is 99.47%; the desorption rate of V is 98.67%; the concentration of V2O5 in the vanadium-rich solution is 27.96 g / L; the concentration of Fe is 0.10 g / L.

[0078] Example 3

[0079] A method for separating and extracting vanadium from a high-acidity vanadium-containing solution. The method for separating and extracting vanadium in this example is carried out according to the following Step 1 and Step 2 by using a system for separating and extracting vanadium:

[0080] As Figure 1 and Figure 2 shown, the system for separating and extracting vanadium is composed of two parts of ion exchange columns. The first part of the ion exchange column is composed of n first ion exchange columns connected in parallel, and the second part of the ion exchange column is composed of m second ion exchange columns connected in series; in this example: n = 4; m = 8.

[0081] Step 1. Resin adsorption

[0082] The resin adsorption method comprises the following steps: simultaneously flowing a high-acidity vanadium-containing solution into a first ion exchange column 1, a first ion exchange column 2, ..., and a first ion exchange column 4 of a first part of the ion exchange column at a flow rate of 1.0 BV / h; the preliminarily adsorbed high-acidity vanadium-containing solution flowing out of the first part of the ion exchange column then flows through a second ion exchange column 1, a second ion exchange column 2, ..., and a second ion exchange column 8 of a second part of the ion exchange column at a flow rate four times that of 1.0 BV / h; and when the vanadium concentration of the adsorption residual solution flowing out of the second ion exchange column 8 reaches 5% of the vanadium concentration in the high-acidity vanadium-containing solution, stopping the flow of the high-acidity vanadium-containing solution to obtain a loaded resin and an adsorption residual solution.

[0083] The high-acidity vanadium-containing solution has a pH of 0.8, a V(V) concentration of 4.4 g / L, and a Fe(III) concentration of 7.5 g / L.

[0084] The resin filled in the first part of the ion exchange column is "modified resin for extracting vanadium from high-acidity vanadium-containing solution", and the volume of the resin filled in the first part of the ion exchange column is 1BV, 1BV = 3.53m 3 The resin filled in the second part of the ion exchange column is the same as the resin filled in the first part of the ion exchange column, and the volume of the resin filled in the second part of the ion exchange column is 2BV.

[0085] The preparation method of the "modified resin for extracting vanadium from a high-acidity vanadium-containing solution" is as follows: ingredients are prepared according to a solid-liquid ratio of aminophosphoric acid-type chelating resin to ethanol of 1:10 kg / L, mixed to obtain a mixture, and then ultrasonically disperse the mixture for 15 minutes, solid-liquid separation, to obtain a resin to be treated and a pretreatment liquid; aminosulfonic acid is uniformly added to the resin to be treated at a temperature of 80°C and a rotation speed of 400 r / min, the volume of the added aminosulfonic acid being 8 times the volume of the resin to be treated; stirring is continued for 36 hours, solid-liquid separation is carried out, to obtain a modified residual liquid and a treated resin; the treated resin is allowed to stand for 36 hours, and washed with deionized water until the pH of the washing liquid reaches 7, to obtain the modified resin for extracting vanadium from a high-acidity vanadium-containing solution.

[0086] The power of the ultrasonic wave is 120W.

[0087] Step 2: Resin desorption

[0088] The resin desorption method is as follows: First, 40 BV of deionized water flows countercurrently through the second ion exchange column 8, the second ion exchange column 7,..., the second ion exchange column 1 at a flow rate of 3 BV / h in sequence. The first-stage washing wastewater flowing out from the second ion exchange column 1 then flows countercurrently into 4 first ion exchange columns for washing at a flow rate of 1 / 4 times 3 BV / h, obtaining the resin to be desorbed and the second-stage washing wastewater; then, 20 BV of desorbent flows countercurrently through the second ion exchange column 8, the second ion exchange column 7,..., the second ion exchange column 1 at a flow rate of 0.2 BV / h in sequence. The desorbing solution flowing out from the second ion exchange column 1 then flows countercurrently into 4 first ion exchange columns for desorption at a flow rate of 1 / 4 times 0.2 BV / h, obtaining the desorbed resin and the vanadium-rich solution.

[0089] The desorbent is a mixed solution of NaOH solution and NaCl solution, and the molar ratio of NaOH solution to NaCl solution is 8:1; the concentration of the NaOH solution is 6 mol / L, and the concentration of the NaCl solution is 0.75 mol / L.

[0090] The 4 first ion exchange columns are the same. The diameter of each first ion exchange column is 1.5 m, and the ratio of the height to the diameter of each first ion exchange column is 2:1; the 8 second ion exchange columns are the same. The diameter of each second ion exchange column is 1.5 m, and the ratio of the height to the diameter of each second ion exchange column is 4:1.

[0091] The concentration of the sulfamic acid is 0.85 mol / L.

[0092] In this embodiment: The adsorption rate of V in the high-acidity vanadium-containing solution is 99.79%; the desorption rate of V is 99.51%; the concentration of V2O5 in the vanadium-rich solution is 29.68 g / L; the concentration of Fe is 0.08 g / L.

[0093] This specific embodiment has the following positive effects compared with the prior art:

[0094] 1. This specific embodiment uses sulfamic acid to react with the amino-phosphoric acid type chelating resin for modification. During the reaction, the sulfamic acid contacts the amino-phosphoric acid type chelating resin, breaking the -NH bond on the resin, causing the H connected to -N to be removed, forming a sulfonamide group, and obtaining a modified resin (hereinafter referred to as "modified resin") for extracting vanadium from high-acidity vanadium-containing solutions. During the modification process, no toxic substances volatilize, the modifier has no odor and low toxicity to the human body, and is environmentally friendly; this specific embodiment directly uses the high-acidity vanadium-containing solution as the adsorption stock solution, reducing the process of adjusting the pH with alkali agents such as sodium hydroxide and calcium hydroxide, and no neutralization slag is generated, which is beneficial to environmental protection.

[0095] 2. The resin filled in the first ion exchange column and the second ion exchange column in this specific embodiment is a modified resin, which can extract vanadium from a high-acidity vanadium-containing solution with a pH of 0 to 1. Under high-acidity conditions, the form of vanadium in the solution is VO2 + , and the modified resin is prone to chelate with VO2 + under acidic conditions, and has higher selectivity for vanadium. In addition, the phosphate groups on the modified resin are strongly acidic cationic groups, which can undergo cation exchange with VO2 + in the solution. The modification changes the nature of the amino group (-NH) of the functional group of the amino-phosphoric acid chelating resin, greatly reducing the chelation effect between the modified resin and iron in the solution and strengthening the separation effect of vanadium and impurity iron.

[0096] 3. This specific embodiment uses the first part of the ion exchange column and the second part of the ion exchange column to purify and enrich the high-acidity vanadium-containing solution. The first part of the ion exchange column is in parallel, and preliminarily adsorbs vanadium in the high-acidity vanadium-containing solution at a flow rate of 1 to 1.5 BV / h; the second part of the ion exchange column is in series, and re-adsorbs the high-acidity vanadium-containing solution flowing out of the first part of the ion exchange column at a flow rate n times that when flowing into the first ion exchange column. Through multi-stage adsorption, the adsorption rate of vanadium > 99% is achieved. The adsorption law of the modified resin for vanadium is to adsorb quickly first, and then slowly until adsorption equilibrium. Therefore, this specific embodiment sets up two parts of ion exchange columns for adsorption. The adsorption flow rate of the first part of the ion exchange column is slow, so that the modified resin has enough contact time with vanadium; the adsorption flow rate of the second part of the ion exchange column is faster and the number of stages increases, so that the modified resin has enough adsorption sites for vanadium adsorption, so the adsorption rate of vanadium > 99% is achieved.

[0097] 4. This specific embodiment uses a mixed solution of sodium hydroxide and sodium chloride to desorb the resin to be desorbed. Sodium hydroxide is an alkaline desorbing agent. When flowing through the resin to be desorbed in the first and second parts of the ion exchange column, it changes the pH environment of the resin to be desorbed, so that the vanadium on the resin to be desorbed changes from the cation form of VO2 + to the vanadate anion form and is thus desorbed into the vanadium-rich solution, achieving a vanadium desorption rate > 98%, the iron content in the vanadium-rich solution is less than 0.12 g / L, and the vanadium-iron separation effect is good; the concentration of V2O5 in the vanadium-rich solution is 23 to 30 g / L, and the vanadium enrichment effect is good.

[0098] Therefore, this specific embodiment has the characteristics of a short process and environmental friendliness, and has a good separation effect between vanadium and impurity iron.

Claims

1. A method for separating and extracting vanadium from a high-acidity vanadium-containing solution, characterized in that The method for separating and extracting vanadium is as follows: using a system for separating and extracting vanadium, the following steps are carried out: Step 1: Resin adsorption The method of resin adsorption is as follows: flowing a high-acidity vanadium-containing solution into the first ion exchange column 1, the first ion exchange column 2,..., the first ion exchange column n of the first part of the ion exchange column at a flow rate of 1-1.5 BV / h simultaneously; the preliminarily adsorbed high-acidity vanadium-containing solution flowing out of the first part of the ion exchange column then flows through the second ion exchange column 1, the second ion exchange column 2,..., the second ion exchange column m of the second part of the ion exchange column in turn at a flow rate of n times 1-1.5 BV / h. When the vanadium concentration of the adsorption residual liquid flowing out of the second ion exchange column m is 3-5% of the vanadium concentration in the high-acidity vanadium-containing solution, stop flowing the high-acidity vanadium-containing solution to obtain the loaded resin and the adsorption residual liquid; The high-acidity vanadium-containing solution: pH is 0-1; V(V) concentration < 4.5 g / L; Fe(III) concentration < 8 g / L; The resin filled in the first part of the ion exchange column is "modified resin for extracting vanadium from high-acidity vanadium-containing solution", and the volume of the resin filled in the first part of the ion exchange column is 1 BV, where 1 BV = 0.20 - 3.53 m 3 ; The resin filled in the second part of the ion exchange column is the same as that filled in the first part of the ion exchange column, and the volume of the resin filled in the second part of the ion exchange column is 2 BV; The preparation method of the "modified resin for extracting vanadium from high-acidity vanadium-containing solution" is as follows: proportioning amino-phosphoric acid type chelating resin and ethanol according to a solid-liquid ratio of 1:(5-10) Kg / L, mixing to obtain a mixed material, then ultrasonically dispersing the mixed material for 5-15 min, performing solid-liquid separation to obtain the resin to be treated and the pretreatment liquid; under the conditions of a temperature of 40-80 °C and a rotation speed of 240-400 r / min, uniformly adding aminosulfonic acid to the resin to be treated, and the volume of the added aminosulfonic acid is 5-8 times the volume of the resin to be treated; then continue to stir for 20-36 h, perform solid-liquid separation to obtain the modified residual liquid and the treated resin; let the treated resin stand for 24-36 h, and wash it with deionized water until the pH of the washing liquid is 6-7 to prepare the modified resin for extracting vanadium from high-acidity vanadium-containing solution; The functional group of the amino-phosphoric acid type chelating resin is -CH2NHCH2PO3 2- ; The power of the ultrasonic wave is 60-120 W; Step 2: Resin desorption The resin desorption method is as follows: first flowing 10-40 BV of deionized water through the second ion exchange column m, the second ion exchange column m-1,..., the second ion exchange column 1 in turn at a flow rate of 3-5 BV / h in a countercurrent manner, and the first-stage washing wastewater flowing out of the second ion exchange column 1 then flows into n first ion exchange columns for washing in a countercurrent manner at a flow rate of 1 / n times 3-5 BV / h respectively to obtain the resin to be desorbed and the second-stage washing wastewater; Then flowing 5-20 BV of desorbent through the second ion exchange column m, the second ion exchange column m-1,..., the second ion exchange column 1 in turn at a flow rate of 0.2-0.5 BV / h in a countercurrent manner, and the desorbing liquid flowing out of the second ion exchange column 1 then flows into n first ion exchange columns for desorption in a countercurrent manner at a flow rate of 1 / n times 0.2-0.5 BV / h respectively to obtain the desorbed resin and the vanadium-rich liquid; The desorbent is a mixed solution of NaOH solution and NaCl solution, and the molar ratio of NaOH solution to NaCl solution is (5-8):1; the concentration of the NaOH solution is 3-6 mol / L, and the concentration of the NaCl solution is 0.6-0.75 mol / L; The system for separating and extracting vanadium consists of two parts of ion exchange columns. The first part of ion exchange columns is composed of n first ion exchange columns connected in parallel, and the second part of ion exchange columns is composed of m second ion exchange columns connected in series; where: n is any natural number among 2, 3, and 4, and m is any natural number among 2, 3, ……, 7, and 8.

2. The method for separating and extracting vanadium from a high-acidity vanadium-containing solution according to claim 1, wherein The n first ion exchange columns are the same. The diameter of each first ion exchange column is 0.5 - 1.5 m, and the ratio of the height to the diameter of each first ion exchange column is (1 - 2):1; the m second ion exchange columns are the same. The diameter of each second ion exchange column is 0.5 - 1.5 m, and the ratio of the height to the diameter of each second ion exchange column is (2 - 4):

1.

3. The method for separating and extracting vanadium from a high-acidity vanadium-containing solution according to claim 1, characterized in that The concentration of the sulfamic acid is 0.2 - 0.85 mol / L.

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