Process for recovering all components of spent molybdenum catalyst

Abstract

This invention discloses a process for recovering all components of waste molybdenum catalyst, comprising the following steps: S1: The waste molybdenum catalyst raw material is sequentially crushed, roasted at high temperature, ball-milled, water-leached, and impurity removed to obtain leaching residue and a purified liquid containing molybdenum and tungsten; S2: Molybdenum in the purified liquid is adsorbed using an alkaline anion exchange resin, leaving a tungsten-containing adsorption tail liquid, which is then desorbed by the alkaline anion exchange resin to obtain a molybdenum-containing desorbed liquid; S3: The adsorption tail liquid and desorbed liquid obtained in S2 are subjected to solid-liquid separation to obtain tungstic acid and tungsten precipitation mother liquor, and molybdic acid and molybdenum precipitation mother liquor, respectively. The tungsten precipitation mother liquor and molybdenum precipitation mother liquor are then adsorbed using an alkaline anion exchange resin, and the tail liquid remaining after adsorption is concentrated and crystallized to obtain sodium sulfate. This invention can efficiently leach and recover molybdenum, tungsten, aluminum, nickel, etc. from waste molybdenum catalyst, realizing the resource utilization of all components of waste molybdenum catalyst.

Description

Technical Field

[0001] This invention relates to the field of waste catalyst resource utilization technology, and in particular to a process for recovering all components of waste molybdenum catalyst. Background Technology

[0002] Waste catalysts represent a vast resource treasure trove. Compared to raw metal ores, the metals in waste catalysts have advantages such as simpler chemical composition, easier compound morphology for recovery, and higher metal content. Currently, there is considerable research in China on molybdenum-containing waste catalysts, with various processes employed. Generally speaking, molybdenum recovery methods from molybdenum-containing catalysts are mainly divided into dry methods, wet methods, and other methods. Dry methods include high-temperature smelting and oxidative roasting-chlorination volatilization, while wet methods include acid leaching, alkaline leaching, water leaching, and combined leaching.

[0003] Among the publicly available patent documents in China, CN115074554A discloses a method that uses oxygen-enriched roasting and oxalic acid leaching to recover molybdenum and nickel, with a molybdenum and nickel recovery rate of over 95%, but acetate ions are introduced in the process; in patent document CN110451563A, the disclosed method uses oxidative roasting, water leaching, extraction separation, concentration and crystallization to recover molybdenum and prepare sodium molybdate, but the remaining elements are not recovered; in patent document CN113564386B, a method for oxidizing waste catalyst with hydrogen peroxide and leaching with ammonia is described, but only molybdenum is recovered.

[0004] As can be seen from the above, the existing methods for recycling spent molybdenum catalysts mainly focus on the recovery of elements such as molybdenum and tungsten. Therefore, a method is needed that not only efficiently leaches and recovers high-value elements such as molybdenum and tungsten, but also recovers the alumina and nickel carriers of the spent catalysts. Summary of the Invention

[0005] The purpose of this invention is to provide a recycling process for all components of waste molybdenum catalysts, which can efficiently leach and recover molybdenum, tungsten, aluminum, nickel and other components from waste molybdenum catalysts, realize the resource utilization of all components of waste molybdenum catalysts, thereby alleviating environmental pollution and achieving a win-win situation for economic benefits and environmental protection.

[0006] To achieve the above objectives, the following technical solution is adopted:

[0007] A process for recovering all components of spent molybdenum catalyst includes the following steps:

[0008] S1: The waste molybdenum catalyst raw material is crushed, roasted at high temperature, ball-milled, water-leached, and impurity removed in sequence to obtain leaching residue and purified liquid containing molybdenum and tungsten;

[0009] S2: Use an alkaline anion exchange resin to adsorb molybdenum in the purified solution. After adsorption, the adsorbed tail liquid containing tungsten is left. Then, the alkaline anion exchange resin is desorbed to obtain a desorbed solution containing molybdenum.

[0010] S3: The adsorption tail liquid and desorption liquid obtained from S2 are subjected to solid-liquid separation to obtain tungstic acid and tungsten precipitation mother liquor and molybdenum acid and molybdenum precipitation mother liquor, respectively. The tungsten precipitation mother liquor and molybdenum precipitation mother liquor are then adsorbed using an alkaline anion exchange resin, and the tail liquid left after adsorption is concentrated and crystallized to obtain sodium sulfate.

[0011] S4: The leaching residue obtained from S1 is mixed with a certain amount of sodium carbonate, and then subjected to high-temperature roasting and water leaching in sequence to obtain aluminum leaching solution and nickel slag. The aluminum leaching solution is then concentrated and crystallized to obtain sodium aluminate.

[0012] S5: The nickel slag obtained in S4 is subjected to acid leaching, pH adjustment and solid-liquid separation in sequence to obtain aluminum hydroxide and nickel-containing solution;

[0013] S6: After adjusting the pH of the nickel-containing solution obtained in S5, nickel is adsorbed using a cationic chelating resin. The resin is then desorbed, concentrated, and crystallized to obtain nickel sulfate. Meanwhile, the tail liquid left after adsorption is concentrated and crystallized to obtain sodium sulfate.

[0014] Furthermore, in step S1, the waste molybdenum catalyst is first mixed with sodium carbonate and then calcined at high temperature. The amount of sodium carbonate used is between 60-110% of the mass of the waste molybdenum catalyst, and the calcination temperature is between 600-1100℃.

[0015] Furthermore, in step S1, the ball milling time is 2-6 hours, the water immersion temperature is between 80-100℃, and the water immersion time is 2-4 hours.

[0016] Further, in step S2, the pH of the purified solution needs to be adjusted to between 2 and 4 at room temperature using sulfuric acid with a concentration of 50-98%. Then, the molybdenum in the purified solution is adsorbed using an alkaline anion exchange resin. The volume ratio of the purified solution after pH adjustment to the alkaline anion exchange resin is 1:0.5-1. In step S2, the alkaline anion exchange resin is desorbed using NaOH with a concentration of 50-200 g / L.

[0017] Furthermore, in step S3, when performing solid-liquid separation on the adsorption tail liquid and the desorption liquid, firstly, sulfuric acid with a concentration of 50-98% is used to adjust its pH value to below 1.0, and then it is heated at 90-100℃ for 1 hour.

[0018] Furthermore, in step S3, before using alkaline anion exchange resin to adsorb the tungsten precipitation mother liquor and the molybdenum precipitation mother liquor, the pH value of the tungsten precipitation mother liquor and the molybdenum precipitation mother liquor is first adjusted to between 2 and 4 using a 200-400 g / L NaOH solution.

[0019] Furthermore, in step S4, the amount of sodium carbonate used is between 100-140% of the mass of the leaching residue, the roasting temperature is between 900-1100℃, the water leaching temperature is between 80-100℃, and the water leaching time is between 2-4 hours.

[0020] Further, in step S5, the nickel slag is acid-leached with sulfuric acid of 20-40% concentration, wherein the acid-leaching temperature is between 90-100℃, the acid-leaching time is between 2-4h, and the solid-liquid ratio of the acid-leaching mixture is controlled between 5-8.

[0021] Further, in step S5, the pH value of the acid-leached solution is first adjusted to between 3 and 4 using a 200-400 g / L NaOH solution. Then, after stirring for 0.5-2 h, the pH value is adjusted to between 5.0 and 5.5 using a 1-20% NaOH solution. After stirring for 0.5-2 h, the solution is filtered to obtain aluminum hydroxide and nickel-containing solutions, respectively.

[0022] Further, in step S6, the pH of the nickel-containing solution is adjusted using a 200-400 g / L NaOH solution, wherein the pH value is adjusted to 4-6; in step S6, the cation chelating resin is desorbed using a 5-10% sulfuric acid solution.

[0023] By adopting the above solution, the beneficial effects of the present invention are:

[0024] This recycling process enables efficient leaching and recovery of molybdenum, tungsten, aluminum, nickel, and other components from waste molybdenum catalysts, achieving full resource utilization of the waste molybdenum catalysts. This can alleviate environmental pollution and achieve a win-win situation for both economic benefits and environmental protection. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating the principle of the present invention. Detailed Implementation

[0026] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0027] Reference Figure 1 As shown, this invention provides a process for recovering all components of waste molybdenum catalyst, comprising the following steps:

[0028] S1: The waste molybdenum catalyst raw material is crushed, roasted at high temperature, ball-milled, water-leached, and impurity removed in sequence to obtain leaching residue and purified liquid containing molybdenum and tungsten.

[0029] In this step, the waste molybdenum catalyst raw material is first coarsely crushed using a crusher, and the resulting product is screened. The waste molybdenum catalyst is then mixed with sodium carbonate and calcined at high temperature in a rotary kiln. At high temperature, sodium carbonate can react with molybdenum and tungsten in the catalyst to form soluble sodium salts. The amount of sodium carbonate used is between 60-110% of the mass of the waste molybdenum catalyst, and the calcination temperature is between 600-1100℃ to obtain calcined clinker.

[0030] Subsequently, after the calcined clinker is cooled, it is fed into a ball mill and ball-milled for 2-6 hours to allow the molybdenum, tungsten and sodium carbonate in the waste molybdenum catalyst to react more fully. After ball milling, the ball-milled material is obtained.

[0031] Subsequently, the ball milling material is introduced into the reactor via a transfer pump, and then 2-5 times the volume of water is added. At a leaching temperature of 80-100℃ and a leaching time of 2-4 hours, the water-soluble components are leached out, yielding a leachate and a leaching residue. The main components of the leachate are sodium tungstate, sodium molybdate, and impurities such as aluminum, phosphorus, and silicon. After adjusting the pH value and adding an appropriate amount of magnesium sulfate for impurity removal, a purified solution containing molybdenum and tungsten and a small amount of impurity-removed residue can be obtained.

[0032] S2: Use an alkaline anion exchange resin to adsorb molybdenum in the purified solution. After adsorption, an adsorption tail liquid containing tungsten is left. Then, the alkaline anion exchange resin is desorbed to obtain a desorbed solution containing molybdenum.

[0033] The purified solution obtained in step S1 needs to have its pH adjusted to between 2 and 4 at room temperature using 50-98% sulfuric acid. Then, molybdenum in the purified solution is adsorbed using an alkaline anion exchange resin. The volume ratio of the purified solution after pH adjustment to the alkaline anion exchange resin is 1:0.5-1. As the purified solution flows through the resin, the molybdenum content in the purified solution can be reduced to 0-100 ppm. Subsequently, the resin is desorbed using 50-200 g / L NaOH to obtain a molybdenum-containing desorbed solution. After adsorption, a tungsten-containing tail liquid will remain.

[0034] S3: The adsorption tail liquid and desorption liquid obtained from S2 are subjected to solid-liquid separation to obtain tungstic acid and tungsten precipitation mother liquor and molybdic acid and molybdenum precipitation mother liquor, respectively. The tungsten precipitation mother liquor and molybdenum precipitation mother liquor are then adsorbed using an alkaline anion exchange resin, and the tail liquid left after adsorption is concentrated and crystallized to obtain sodium sulfate.

[0035] In this step, firstly, sulfuric acid with a concentration of 50-98% is used to adjust the pH value to below 1.0. Then, it is heated at 90-100℃ for 1 hour to perform solid-liquid separation, so as to obtain tungstic acid and tungsten precipitation mother liquor, and molybdic acid and molybdenum precipitation mother liquor, respectively. Then, the pH value of the tungsten precipitation mother liquor and molybdenum precipitation mother liquor is adjusted to between 2 and 4 using a 200-400 g / L NaOH solution. The tungsten precipitation mother liquor is used to adsorb residual tungsten, and the molybdenum precipitation mother liquor is used to adsorb residual molybdenum. After the adsorption is completed, the resin is desorbed using 50-200 g / L NaOH. The desorbed liquid is returned to the tungsten and molybdenum precipitation stage. The adsorption tail liquid is concentrated and crystallized to obtain sodium sulfate.

[0036] S4: The leaching residue obtained in S1 is mixed with a certain amount of sodium carbonate, and then subjected to high-temperature roasting and water leaching in sequence to obtain aluminum leaching solution and nickel slag. The aluminum leaching solution is then concentrated and crystallized to obtain sodium aluminate.

[0037] In this step, the leaching residue obtained from S1 is first mixed with a certain amount of sodium carbonate and then calcined in a rotary kiln to obtain calcined clinker. During the calcination process, the aluminum in the leaching residue reacts with sodium carbonate to form sodium aluminate. The amount of sodium carbonate used is between 100-140% of the mass of the leaching residue, and the calcination temperature is between 900℃ and 1100℃. Subsequently, the calcined clinker is introduced into a reactor through a transfer pump, and then 8-10 times the volume of water is added. Under the conditions of leaching temperature of 80-100℃ and leaching time of 2-4 hours, the water-soluble components are leached to obtain aluminum leaching solution and nickel slag. The aluminum leaching solution is concentrated and crystallized to obtain sodium aluminate product.

[0038] S5: The nickel slag obtained in S4 is subjected to acid leaching, pH adjustment and solid-liquid separation in sequence to obtain aluminum hydroxide and nickel-containing solution.

[0039] In this step, nickel slag is first mixed with sulfuric acid and leached at 90-100℃ for 2-4 hours to obtain an acid leaching mixture. The solid-liquid ratio of the acid leaching mixture is controlled between 5 and 8, and the sulfuric acid concentration is 20-40%. Subsequently, the pH value of the solution is adjusted to 3-4 using 200-400 g / L NaOH solution and stirred for 0.5-2 hours. Then, the pH value is adjusted to 5.0-5.5 using 1-20% NaOH solution and stirred for another 0.5-2 hours before filtration to obtain aluminum hydroxide and a nickel-containing solution.

[0040] S6: After adjusting the pH of the nickel-containing solution obtained in S5, nickel is adsorbed using a cationic chelating resin. The resin is then desorbed, concentrated, and crystallized to obtain nickel sulfate. Meanwhile, the tail liquid left after adsorption is concentrated and crystallized to obtain sodium sulfate.

[0041] In this step, the pH of the nickel-containing solution is adjusted to 4-6 using a 200-400 g / L NaOH solution. Then, the nickel is adsorbed using a cationic chelating resin. After adsorption, the nickel is desorbed using 5-10% sulfuric acid. The desorbed solution is concentrated and crystallized to obtain nickel sulfate. The tail liquid left after adsorption is concentrated and crystallized to obtain sodium sulfate.

[0042] In this recycling process, the waste molybdenum catalyst undergoes screening, segmented alkaline leaching and roasting, and ball milling. This ensures efficient leaching of molybdenum and tungsten while maintaining low aluminum leaching, reducing the need for impurity removal during the molybdenum and tungsten removal process. The leaching stage achieves a molybdenum and tungsten extraction rate of >98% and an aluminum extraction rate of <20%. The leaching solution has a relatively simple composition, facilitating recycling. Furthermore, using this process, the overall recovery rate of molybdenum, tungsten, nickel, and aluminum from the waste molybdenum catalyst is >95%.

[0043] The following two specific embodiments illustrate the point:

[0044] Example 1:

[0045] 1) Take 100 kg of crushed and screened waste molybdenum catalyst and mix it evenly with 80 kg of sodium carbonate powder. Place it in a rotary kiln at 1100℃ and calcine for 2 hours. After calcination, take it out and cool it. After cooling, put the material into a ball mill and ball mill for 4 hours. After cooling, add 3 times the volume of water to the calcined clinker and dissolve it at 95℃ for 1 hour. After filtration, the first leaching residue and the first leaching liquid are obtained.

[0046] 2) The leachate obtained above is subjected to impurity removal treatment. The purified solution is treated with 98% sulfuric acid to adjust the pH to 4.0, and then molybdenum is adsorbed using a first-type basic anion exchange resin. The volume ratio of the first-type basic anion exchange resin to the first leachate is 1:1, resulting in the first-type resin and the first adsorption tail liquid after adsorption is completed. The first-type resin after adsorption is completed is desorbed using a 5% sodium hydroxide solution. The pH of the desorption solution is adjusted to 1.0 using 98% sulfuric acid. After stirring for 30 minutes, solid-liquid separation is performed to obtain molybdic acid and molybdenum precipitation mother liquor. The pH of the molybdenum precipitation mother liquor is adjusted to 4.0 using a 30% NaOH solution. The first-type basic anion exchange resin is used to adsorb all the molybdenum in the molybdenum precipitation mother liquor. The volume ratio of the first-type basic anion exchange resin to the molybdenum precipitation liquid is 0.5:1, resulting in the second adsorption tail liquid. The resin is desorbed using a 5% sodium hydroxide solution. The desorbed solution is returned to the molybdenum precipitation process. The adsorption tail liquid is concentrated and crystallized to obtain sodium sulfate.

[0047] 3) The pH of the first adsorption tail liquid in step (2) is adjusted to 1 using 98% sulfuric acid. After stirring at 90°C for 2 hours, the solid and liquid are separated to obtain tungstic acid and tungsten precipitation mother liquor. The pH of the tungsten precipitation mother liquor is adjusted to 3.0 using 30% NaOH solution. Then, the tungsten in the mother liquor is adsorbed using a second type of alkaline anion exchange resin. The volume ratio of the second type of alkaline anion exchange resin to the tungsten production liquid is 0.5:1 to obtain the third adsorption tail liquid. The resin is desorbed using 5% sodium hydroxide solution. The desorbed liquid is returned to the tungsten precipitation process. The second and third adsorption tail liquids are concentrated and crystallized to obtain sodium sulfate.

[0048] 4) Mix the first leaching residue from step (1) with 65 kg of sodium carbonate evenly, place it in a rotary kiln at 900℃ for 2 hours, take it out and cool it. After cooling, take the calcined material and add 10 times the volume of water, dissolve it at 95℃ for 2 hours, filter to obtain the second leaching residue and the second leaching liquid, concentrate and crystallize the second leaching liquid to obtain sodium aluminate product.

[0049] 5) The second leaching residue from step (4) is mixed with 50L of 20% sulfuric acid and leached at 90℃ for 2h to obtain the third leaching solution. The pH of the third leaching solution is adjusted to 3.5 using 200-400g / L NaOH solution and stirred for 1h. Then, the pH is adjusted to 5.0 using 5% NaOH solution and stirred for 1h. After filtration, aluminum hydroxide and nickel-containing solution are obtained. The pH of the nickel-containing solution is adjusted to 5 using 200-400g / L NaOH solution. Then, nickel is adsorbed using cationic chelating resin with a volume ratio of 1:1 between the cationic chelating resin and the mixed solution. After adsorption is complete, desorption is performed using 10% sulfuric acid solution. The desorption solution is concentrated and crystallized to obtain nickel sulfate product. The adsorption tail liquid is concentrated and crystallized to obtain sodium sulfate.

[0050] Example 2:

[0051] 1) Take 100 kg of crushed and screened waste molybdenum catalyst and mix it evenly with 80 kg of sodium carbonate powder. Place it in a rotary kiln at 1100℃ for 3 hours, then take it out and cool it. After cooling, put the material into a ball mill and ball mill for 5 hours. After cooling, take the calcined material, add 4 times the volume of water, and dissolve it at 90℃ for 1 hour. Filter to obtain the first leaching residue and the first leaching liquid.

[0052] 2) The leachate obtained in step (1) is subjected to impurity removal treatment. The purified liquid obtained after impurity removal is adjusted to pH 3.5 with 98% sulfuric acid. Then, molybdenum is adsorbed using a first-type basic anion exchange resin. The volume ratio of the first-type basic anion exchange resin to the first leachate is 1:1. The first-type resin and the first adsorption tail liquid are obtained after adsorption. The first-type resin after adsorption is desorbed with 5% sodium hydroxide solution. The pH of the desorbed solution is adjusted to 1 with 98% sulfuric acid. After stirring for 60 minutes, the solid and liquid are separated to obtain molybdic acid and molybdenum precipitation mother liquor. The pH of the molybdenum precipitation mother liquor is adjusted to 4.0 with 30% NaOH solution. The molybdenum in the molybdenum precipitation mother liquor is adsorbed by the first-type basic anion exchange resin. The volume ratio of the first-type basic anion exchange resin to the molybdenum precipitation liquid is 0.5:1. The second adsorption tail liquid is obtained. The resin is desorbed with 5% sodium hydroxide solution. The desorbed liquid is returned to the molybdenum precipitation process. The adsorption tail liquid is concentrated and crystallized to obtain sodium sulfate.

[0053] 3) The pH of the first adsorption tail liquid in step (2) is adjusted to 0.5 using 98% sulfuric acid. After stirring at 90°C for 3 hours, the solid and liquid are separated to obtain tungstic acid and tungsten precipitation mother liquor. The pH of the tungsten precipitation mother liquor is adjusted to 3.0 using 30% NaOH solution. The tungsten in the mother liquor is adsorbed using a second type of alkaline anion exchange resin. The volume ratio of the second type of alkaline anion exchange resin to the tungsten production liquid is 0.5:1 to obtain the third adsorption tail liquid. The resin is desorbed using 5% sodium hydroxide solution. The desorbed liquid is returned to the tungsten precipitation process. The second and third adsorption tail liquids are concentrated and crystallized to obtain sodium sulfate.

[0054] 4) Mix the first leaching residue from step (1) with 65 kg of sodium carbonate evenly, place it in a rotary kiln at 1000℃, calcine for 2 hours, then take it out and cool it. After cooling, take the calcined material and add 8 times the volume of water, dissolve it at 90℃ for 3 hours, filter to obtain the second leaching residue and the second leaching liquid, concentrate and crystallize the second leaching liquid to obtain sodium aluminate product.

[0055] 5) The second leaching residue from step (4) is mixed with 50L of 20% sulfuric acid and leached at 90℃ for 4h to obtain the third leaching solution. The third leaching solution is adjusted to pH 4 using 200-400g / L NaOH solution. After stirring for 0.5h, the pH is adjusted to 5.2 using 5% NaOH solution. After stirring for 1h, the solution is filtered to obtain aluminum hydroxide and a nickel-containing solution. The nickel-containing solution is adjusted to pH 6.0 using 200-400g / L NaOH solution. The nickel is adsorbed using a cationic chelating resin with a volume ratio of 1:1 between the cationic chelating resin and the mixed solution. After adsorption, the nickel is desorbed using 10% sulfuric acid solution. The desorbed solution is concentrated and crystallized to obtain nickel sulfate product. The adsorption tail liquid is concentrated and crystallized to obtain sodium sulfate.

[0056] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for the recovery of all components of spent molybdenum catalyst, characterized in that, Includes the following steps: S1: The waste molybdenum catalyst raw material is crushed, roasted at high temperature, ball-milled, water-leached, and impurity removed in sequence to obtain leaching residue and purified liquid containing molybdenum and tungsten; S2: Use an alkaline anion exchange resin to adsorb molybdenum in the purified liquid. After adsorption, the adsorbed tail liquid containing tungsten is left. Then, the alkaline anion exchange resin is desorbed to obtain a desorbed liquid containing molybdenum. S3: The adsorption tail liquid and desorption liquid obtained from S2 are subjected to solid-liquid separation to obtain tungstic acid and tungsten precipitation mother liquor and molybdenum acid and molybdenum precipitation mother liquor, respectively. The tungsten precipitation mother liquor and molybdenum precipitation mother liquor are then adsorbed using an alkaline anion exchange resin, and the tail liquid left after adsorption is concentrated and crystallized to obtain sodium sulfate. S4: The leaching residue obtained from S1 is mixed with a certain amount of sodium carbonate, and then subjected to high-temperature roasting and water leaching in sequence to obtain aluminum leaching solution and nickel slag. The aluminum leaching solution is then concentrated and crystallized to obtain sodium aluminate. S5: The nickel slag obtained in S4 is subjected to acid leaching, pH adjustment and solid-liquid separation in sequence to obtain aluminum hydroxide and nickel-containing solution; S6: After adjusting the pH of the nickel-containing solution obtained in S5, nickel is adsorbed using a cationic chelating resin. The resin is then desorbed, concentrated, and crystallized to obtain nickel sulfate. Meanwhile, the tail liquid left after adsorption is concentrated and crystallized to obtain sodium sulfate. In step S1, the waste molybdenum catalyst is first mixed with sodium carbonate and then calcined at high temperature. The amount of sodium carbonate used is between 60-110% of the mass of the waste molybdenum catalyst, and the calcination temperature is between 600-1100℃. In step S1, the ball milling time is 2-6 hours, the water immersion temperature is between 80-100℃, and the water immersion time is 2-4 hours. In step S2, the pH of the purification solution needs to be adjusted to between 2 and 4 at room temperature using 50-98% sulfuric acid. Then, the molybdenum in the purification solution is adsorbed using an alkaline anion exchange resin. The volume ratio of the purified solution after pH adjustment to the alkaline anion exchange resin is 1:0.5-1. In step S2, the alkaline anion exchange resin is desorbed using 50-200 g / L NaOH. In step S3, when performing solid-liquid separation on the adsorption tail liquid and desorption liquid, first use sulfuric acid with a concentration of 50-98% to adjust its pH value to below 1.0, and then heat it at 90-100℃ for 1 hour.

2. The process for the recovery of the total content of spent molybdenum catalyst according to claim 1, characterized in that, In step S3, before using alkaline anion exchange resin to adsorb tungsten precipitation mother liquor and molybdenum precipitation mother liquor, the pH value of the tungsten precipitation mother liquor and molybdenum precipitation mother liquor is first adjusted to between 2 and 4 using a 200-400 g / L NaOH solution.

3. The process for the recovery of all components of spent molybdenum catalyst according to any one of claims 1 to 2, characterized in that, In step S4, the amount of sodium carbonate used is between 100-140% of the mass of the leaching residue, the calcination temperature is between 900-1100℃, the water leaching temperature is between 80-100℃, and the water leaching time is between 2-4 hours.

4. The process for the recovery of all components of spent molybdenum catalyst according to any one of claims 1 to 2, characterized in that, In step S5, the nickel slag is acid-leached with sulfuric acid of 20-40% concentration. The acid-leaching temperature is between 90-100℃, the acid-leaching time is between 2-4 hours, and the solid-liquid ratio of the acid-leaching mixture is controlled between 5-8.

5. The process for the recovery of all components of spent molybdenum catalyst according to any one of claims 1 to 2, characterized in that, In step S5, the pH of the acid-leached solution is first adjusted to between 3 and 4 using a 200-400 g / L NaOH solution. Then, after stirring for 0.5-2 h, the pH is adjusted to between 5.0 and 5.5 using a 1-20% NaOH solution. After stirring for 0.5-2 h, the solution is filtered to obtain aluminum hydroxide and nickel-containing solutions, respectively.

6. The process for recovering all components of spent molybdenum catalyst according to any one of claims 1 to 2, characterized in that, In step S6, the pH of the nickel-containing solution is adjusted using a 200-400 g / L NaOH solution, wherein the pH value is adjusted to 4-6; in step S6, the cation chelating resin is desorbed using a 5-10% sulfuric acid solution.

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