A method for short-process full-component cascade recovery of spent hydrogenation catalysts

Abstract

This application provides a short-process, full-component, cascaded recovery method for spent hydrogenation catalysts, relating to the field of solid waste disposal. The recovery method for spent hydrogenation catalysts includes: roasting the spent hydrogenation catalyst with sodium carbonate to obtain a roasting product; leaching the roasting product with water to obtain a leachate and a leaching residue; extracting the leachate with an extractant to obtain a vanadium-molybdenum-containing organic phase; sequentially back-extracting the vanadium-molybdenum-containing organic phase with a strong-alkaline back-extractant and a weak-alkaline back-extractant to obtain a vanadium back-extractant and a molybdenum back-extractant; subjecting the vanadium back-extractant to vanadium precipitation to obtain ammonium metavanadate; acidifying the molybdenum back-extractant to precipitate molybdenum to obtain ammonium molybdate; sintering the leaching residue with an alkaline substance; leaching the resulting roasted sand with water to obtain a water-leached residue and a filtrate; subjecting the filtrate to aluminum precipitation to obtain aluminum hydroxide, alumina, or boehmite; and reducing and smelting the water-leached residue to obtain a nickel-iron alloy. This application can achieve comprehensive recovery of all components (vanadium, molybdenum, nickel, aluminum, and sulfur), realizing the high-value utilization of all components of spent hydrogenation catalysts.

Description

Technical Field

[0001] This application relates to the field of solid waste disposal, and in particular to a method for short-process full-component cascade recovery of waste hydrogenation catalysts. Background Technology

[0002] Hydrogenation catalysts are mainly used in hydrodesulfurization and hydronitrogenation reactions in the petroleum refining process. After a period of use, the enrichment of sulfur and vanadium in the hydrogenation catalyst will lead to poisoning of the spent catalyst. Generally, the hydrogenation catalyst needs to be replaced every 3 to 4 years.

[0003] Existing methods for recovering spent hydrogenation catalysts include the following process: Figure 1 As shown, existing waste hydrogenation catalyst disposal processes require pretreatment such as heating, vacuum deoiling, and crushing before roasting, resulting in long process flows and high energy consumption. Furthermore, these processes suffer from low vanadium and molybdenum recovery rates, and the reaction of sulfur in the waste catalyst with sodium carbonate during roasting leads to high sodium carbonate consumption and costs. In addition, existing waste hydrogenation catalyst disposal processes have low resource utilization rates; sulfur is typically desulfurized using lime to produce gypsum slag, and the comprehensive recovery of water-leached nickel-aluminum slag is not considered. Moreover, existing waste hydrogenation catalyst disposal processes also suffer from low product purity; vanadium and molybdenum products are typically crude products with low valuation coefficients, requiring further purification and refining. Summary of the Invention

[0004] The purpose of this application is to provide a short-process, full-component cascade recovery method for spent hydrogenation catalysts to solve the above-mentioned problems.

[0005] To achieve the above objectives, this application adopts the following technical solution:

[0006] A method for short-process full-component cascade recovery of spent hydrogenation catalysts includes:

[0007] Waste hydrogenation catalyst was mixed with sodium carbonate and roasted in a fluidized bed roaster to obtain the roasted product.

[0008] The roasted product is leached with water, and after solid-liquid separation, a leachate and a leachate residue are obtained.

[0009] The leachate was extracted with an extractant to separate a vanadium-molybdenum-containing organic phase and a raffinate. The vanadium-molybdenum-containing organic phase was then back-extracted sequentially with a strong alkaline back-extractant and a weak alkaline back-extractant to obtain a vanadium back-extract solution and a molybdenum back-extract solution. The vanadium back-extract solution was mixed with an ammonium salt for vanadium precipitation to obtain ammonium metavanadate. The molybdenum back-extract solution was acidified to precipitate molybdenum to obtain ammonium molybdate.

[0010] The leaching residue is sintered with an alkaline substance, and the resulting calcined sand is leached with water to obtain water-leached residue and filtrate. The filtrate is subjected to aluminum precipitation treatment to obtain an aluminum-containing product. The water-leached residue is mixed with calcium oxide and iron-containing substances and subjected to reduction smelting to obtain a nickel-iron alloy.

[0011] According to embodiments of this application, the spent hydrogenation catalyst, by mass percentage, comprises 1-16 wt% V, 2-10 wt% Mo, 1-6 wt% Ni, 18-40 wt% Al₂O₃, 8-15 wt% S, 10-20 wt% non-volatile carbon deposits, and 5-20 wt% volatile hydrocarbons. The volatile hydrocarbons include hydrocarbons and their derivatives, including nitrogen-containing hydrocarbons. The carbon deposits are solid carbonaceous deposits formed during the use of the spent hydrogenation catalyst due to the deep cracking of hydrocarbons; they are insoluble in conventional organic solvents and can be oxidized to CO₂ at high temperatures. The volatile hydrocarbons are adsorbed or remain in the spent hydrogenation catalyst.

[0012] According to an embodiment of this application, the mass ratio of the waste hydrogenation catalyst to sodium carbonate is 100:(5~20);

[0013] The roasting temperature is 1000℃~1250℃;

[0014] The calcination atmosphere is a strong oxidizing atmosphere, and the oxygen excess coefficient of the strong oxidizing atmosphere is 1.2~1.5;

[0015] The roasting time is 0.5~6.0 h;

[0016] And / or, the roasting process also produces flue gas, the concentration of sulfur dioxide in which is 2.8 to 3.2%.

[0017] According to an embodiment of this application, when the roasted product is leached with water, the leaching liquid-to-solid ratio is (1.5~5.0):1mL / g, the leaching temperature is 10℃~95℃, and the leaching time is 0.3~3.0h.

[0018] According to embodiments of this application, the extractant includes a quaternary ammonium salt anionic extractant, which includes at least one of methyltrioctylammonium chloride, trioctylmethylammonium bromide, and tetrabutylammonium bromide.

[0019] During extraction, the method further includes adding an extraction aid and a diluent to the extractant. The extraction aid includes at least one of n-octanol, isooctanol, and sec-octanol, and the diluent includes at least one of sulfonated kerosene and No. 260 solvent oil. The volume ratio of the extractant to the extraction aid and the diluent is (15~35%):(5~15%):(50~80%).

[0020] The volume ratio of the extracted oil phase to the aqueous phase is 5:1 to 1:2.

[0021] According to an embodiment of this application, the back-extraction treatment of the vanadium-molybdenum-containing organic phase by sequentially using a strong alkaline back-extraction agent and a weak alkaline back-extraction agent includes: back-extracting the vanadium-molybdenum-containing organic phase with a strong alkaline back-extraction agent to obtain a vanadium back-extraction solution and a molybdenum-containing organic phase; and back-extracting the molybdenum-containing organic phase with a weak alkaline back-extraction agent to obtain a molybdenum back-extraction solution.

[0022] According to embodiments of this application, the strongly alkaline back-extraction agent includes at least one of sodium hydroxide solution, sodium carbonate solution, and potassium hydroxide solution;

[0023] The concentration of the strongly basic stripping agent is 0.3~3 mol / L;

[0024] The volume ratio of the oil phase to the water phase in the vanadium back-extraction treatment is 5:1 to 1:1;

[0025] The weakly basic stripping agent includes at least one of ammonia water, ammonium carbonate solution, and ammonium bicarbonate solution, and the concentration of the weakly basic stripping agent is 0.3~3 mol / L;

[0026] The volume ratio of the oil phase to the water phase in the molybdenum back-extraction treatment is 5:1 to 1:1.

[0027] According to embodiments of this application, the alkaline substance includes at least one of sodium hydroxide, potassium hydroxide, and sodium carbonate;

[0028] The mass of the alkaline substance is 0.7 to 1.2 times the mass of the leaching residue;

[0029] The sintering temperature is 400℃~800℃;

[0030] The sintering process takes 0.5 to 3.0 hours.

[0031] According to embodiments of this application, the calcium oxide accounts for 10-30% of the mass of the water-leached residue;

[0032] The iron-containing substance includes iron concentrate;

[0033] The iron-containing substance accounts for 20-50% of the mass of the water-leached residue;

[0034] The reduction smelting temperature is 1000-1300℃.

[0035] Compared with the prior art, the beneficial effects of this application include:

[0036] This application enables the comprehensive recovery of vanadium, molybdenum, nickel, aluminum, and sulfur, achieving high-value utilization of all components from waste hydrogenation catalysts. It solves the problems of existing methods, such as long process flows, high energy consumption, poor product purity, and low resource utilization. Specifically, the method in this application achieves vanadium and molybdenum recovery rates of over 95%, product purity of over 99%, concentrated sulfuric acid product purity of 98%, aluminum recovery rate of over 85%, and nickel recovery rate of over 98%. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation on the scope of this application.

[0038] Figure 1 A flowchart illustrating existing methods for recovering spent hydrogenation catalysts;

[0039] Figure 2 This is a flow chart of the short-process, full-component cascade recovery method for spent hydrogenation catalysts in this application. Detailed Implementation

[0040] As used in this article:

[0041] "Prepared from" is synonymous with "comprising". The terms "comprising", "including", "having", "containing", or any other variations thereof as used herein are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0042] The conjunction "composed of..." excludes any unspecified elements, steps, or components. If used in a claim, this phrase makes the claim closed, excluding materials other than those described, except for associated conventional impurities. When the phrase "composed of..." appears in a clause of the body of a claim rather than immediately following it, it limits only the elements described in that clause; other elements are not excluded from the claim as a whole.

[0043] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually. For example, when the range “1–5” is disclosed, the described range should be interpreted as including ranges “1–4”, “1–3”, “1–2”, “1–2 and 4–5”, “1–3 and 5”, etc. When numerical ranges are described herein, unless otherwise stated, the range is intended to include its endpoints and all integers and fractions within that range.

[0044] In these embodiments, unless otherwise specified, the portions and percentages are all by weight.

[0045] "Parts by mass" refers to the basic unit of measurement that expresses the mass ratio of multiple components. One part can represent any unit mass, such as 1g or 2.689g. If we say that component A has "a" parts by mass and component B has "b" parts by mass, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it can mean that the mass of component A is aK and the mass of component B is bK (where K is any number representing a multiplier). It is important to understand that, unlike parts by mass, the sum of the mass parts of all components is not limited to 100 parts.

[0046] "And / or" is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0047] A method for short-process full-component cascade recovery of spent hydrogenation catalysts, referenced Figure 2 ,include:

[0048] Waste hydrogenation catalyst was mixed with sodium carbonate and roasted in a fluidized bed roaster to obtain the roasted product.

[0049] The roasted product is leached with water, and after solid-liquid separation, a leachate and a leachate residue are obtained.

[0050] The leachate was extracted with an extractant to separate a vanadium-molybdenum-containing organic phase and a raffinate. The vanadium-molybdenum-containing organic phase was then back-extracted sequentially with a strong alkaline back-extractant and a weak alkaline back-extractant to obtain a vanadium back-extract solution and a molybdenum back-extract solution. The vanadium back-extract solution was mixed with an ammonium salt for vanadium precipitation to obtain ammonium metavanadate. The molybdenum back-extract solution was acidified to precipitate molybdenum to obtain ammonium molybdate.

[0051] The leaching residue is sintered with an alkaline substance, and the resulting calcined sand is leached with water to obtain water-leached residue and filtrate. The filtrate is subjected to aluminum precipitation treatment to obtain an aluminum-containing product. The water-leached residue is mixed with calcium oxide and iron-containing substances and subjected to reduction smelting to obtain a nickel-iron alloy.

[0052] The method described in this application eliminates the need for vacuum deoiling and crushing pretreatment of waste hydrogenation catalysts, significantly shortening the process flow.

[0053] According to embodiments of this application, the waste hydrogenation catalyst comprises, by mass percentage, 1-16 wt% V, 2-10 wt% Mo, 1-6 wt% Ni, 18-40 wt% Al2O3, 8-15 wt% S, 10-20 wt% non-volatile carbon deposits, and 5-20 wt% volatile hydrocarbons, wherein the volatile hydrocarbons include hydrocarbons and hydrocarbon derivatives, and the hydrocarbon derivatives include nitrogen-containing hydrocarbons.

[0054] For example, the V content in the spent hydrogenation catalyst is 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, or any value between 1 and 16 wt%; the Mo content in the spent hydrogenation catalyst is 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, or any value between 2 and 10 wt%; the Ni content in the spent hydrogenation catalyst is 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, or any value between 1 and 6 wt%; the Al2O3 content in the spent hydrogenation catalyst is 18 wt%, 20 wt%, 22 wt%, 24 wt%, 26 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%. The content of S in the waste hydrogenation catalyst is 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, or any value between 8 and 15 wt%.

[0055] The content of non-volatile carbon deposits in the spent hydrogenation catalyst is 10 wt%, 12 wt%, 15 wt%, 18 wt%, 18.05 wt%, 19 wt%, 20 wt%, or any value between 10 and 20 wt%; the content of volatile hydrocarbons in the spent hydrogenation catalyst is 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, or any value between 5 and 20 wt%.

[0056] According to an embodiment of this application, the mass ratio of the waste hydrogenation catalyst to sodium carbonate is 100:(5~20);

[0057] For example, the mass ratio of waste hydrogenation catalyst to sodium carbonate is any value between 100:5, 100:10, 100:15, 100:20 or 100:(5~20).

[0058] The method described in this application can ensure that the sodium carbonate addition range can achieve a high conversion rate of vanadium and molybdenum, while avoiding the use of sodium carbonate for sulfur fixation due to excessive sodium carbonate. It can ensure a high desulfurization rate while avoiding redundant material consumption, thus balancing the economic efficiency and high efficiency of the process.

[0059] The roasting temperature is 1000℃~1250℃;

[0060] For example, the roasting temperature is 1000℃, 1050℃, 1100℃, 1150℃, 1200℃, 1250℃ or any value between 1000℃ and 1250℃.

[0061] The roasting atmosphere is a strong oxidizing atmosphere, and the oxygen excess coefficient of the strong oxidizing atmosphere is 1.2 to 1.5; for example, the oxygen excess coefficient of the strong oxidizing atmosphere is 1.2, 1.3, 1.4, 1.5 or any value between 1.2 and 1.5.

[0062] The strong oxidizing atmosphere is oxygen-enriched air; wherein, the oxygen excess coefficient is the ratio of the actual molar amount of oxygen supplied to the theoretical molar amount of oxygen required by the waste hydrogenation catalyst.

[0063] The roasting time is 0.5~6.0h.

[0064] For example, the roasting time can be 0.5h, 1.0h, 2.0h, 3.0h, 4.0h, 5.0h, 6.0h, or any value between 0.5h and 6.0h.

[0065] In some embodiments, the roasting process also generates flue gas, the concentration of which is 2.8-3.2% sulfur dioxide. The flue gas has a high sulfur content and can be used to produce acid. Acid production methods include adsorption, contact, or hydrogen peroxide oxidation. The acid product is concentrated sulfuric acid with a concentration of 20-98%. Waste heat from the flue gas is used to produce steam or generate electricity.

[0066] In some embodiments, calcination is carried out in a strongly oxidizing atmosphere. This allows for the removal of carbon and sulfur from the spent hydrogenation catalyst while simultaneously achieving sodium conversion, with removal rates exceeding 98% for both carbon and sulfur.

[0067] The method described in this application removes more than 98% of the sulfur while completing the sodium conversion by controlling the roasting temperature and roasting atmosphere (strong oxidizing atmosphere). The desulfurized flue gas can be used for acid production, and the consumption of sodium salt additives by sulfur elements during the roasting process is avoided, thus reducing the amount of sodium salt added.

[0068] The temperature range of the method in this application can ensure that vanadium and molybdenum achieve the ideal conversion efficiency and guarantee the yield of the target product; it can also effectively control the conversion rate of aluminum without the need for additional impurity removal steps, thus simplifying the process flow.

[0069] Moreover, the method of this application significantly improves the conversion rate of vanadium and molybdenum in the roasting process through suspension circulating fluidized bed roasting, which can increase the conversion rate of vanadium and molybdenum to more than 95%. At the same time, the system can maintain its own heat balance and does not require external heat source supply, thus greatly reducing energy consumption.

[0070] According to an embodiment of this application, when the roasted product is leached with water, the leaching liquid-to-solid ratio is (1.5~5.0):1mL / g, the leaching temperature is 10℃~95℃, and the leaching time is 0.3~3.0h.

[0071] For example, the leachate liquid-to-solid ratio can be any value between 1.5:1 mL / g, 2.0:1 mL / g, 2.5:1 mL / g, 3.0:1 mL / g, 3.5:1 mL / g, 4.0:1 mL / g, 4.5:1 mL / g, 5.0:1 mL / g, or (1.5~5.0):1 mL / g).

[0072] The leaching temperature is any value between 10℃, 20℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 95℃ or 10℃~95℃.

[0073] The leaching time is 0.3h, 1h, 2h, 3h or any value between 0.3 and 3.0h.

[0074] In some embodiments, the pH of the system during leaching is 8 to 9, for example, the pH of the system during leaching is 8, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.76, 8.8, 8.9, 9 or any value between 8 and 9.

[0075] In some embodiments, the ratio of the molar amount of vanadium to the molar amount of molybdenum in the leachate is 0.1 to 10.

[0076] According to embodiments of this application, the extractant includes a quaternary ammonium salt anionic extractant, which includes at least one of methyltrioctylammonium chloride, trioctylmethylammonium bromide, and tetrabutylammonium bromide.

[0077] During extraction, the method further includes adding an extraction aid and a diluent to the extractant. The extraction aid includes at least one of n-octanol, isooctanol, and sec-octanol, and the diluent includes at least one of sulfonated kerosene and No. 260 solvent oil. The volume ratio of the extractant to the extraction aid and the diluent is (15~35%):(5~15%):(50~80%).

[0078] For example, the volume ratio of extractant to extractant and diluent is any value between 15%:5%:50%, 25%:10%:65%, 35%:15%:80%, or (15~35%):(5~15%):(50~80%).

[0079] The volume ratio of the oil phase to the aqueous phase in the extraction is 5:1 to 1:2. The oil phase includes an extractant, an extraction aid, and a diluent, while the aqueous phase is the leachate to be extracted.

[0080] For example, the volume ratio of the extracted oil phase to the water phase is 5:1, 4:1, 3:1, 2:1, 1:1, 1:2 or any value between 5:1 and 1:2.

[0081] This application employs extraction separation of the leachate, avoiding the consumption of large amounts of acid and alkali due to adjusting the solution pH, while also solving the problems of long separation process and low purity of vanadium-molybdenum products in existing processes.

[0082] According to an embodiment of this application, the back-extraction treatment of the vanadium-molybdenum-containing organic phase by sequentially using a strong alkaline back-extraction agent and a weak alkaline back-extraction agent includes: back-extracting the vanadium-molybdenum-containing organic phase with a strong alkaline back-extraction agent to obtain a vanadium back-extraction solution and a molybdenum-containing organic phase; and back-extracting the molybdenum-containing organic phase with a weak alkaline back-extraction agent to obtain a molybdenum back-extraction solution.

[0083] The method described in this application employs a "vanadium-molybdenum co-extraction-vanadium-molybdenum step-back extraction" process to efficiently separate vanadium and molybdenum from vanadium-molybdenum aqueous leaching solutions, while simultaneously achieving the preparation of high-purity vanadium-molybdenum products, significantly improving product value.

[0084] According to embodiments of this application, the strongly alkaline back-extraction agent includes at least one of sodium hydroxide solution, sodium carbonate solution, and potassium hydroxide solution;

[0085] The concentration of the strongly basic stripping agent is 0.3~3 mol / L; for example, the concentration of the strongly basic stripping agent is 0.3 mol / L, 0.5 mol / L, 1 mol / L, 2 mol / L, 3 mol / L or any value between 0.3 and 3 mol / L.

[0086] The volume ratio of the oil phase to the aqueous phase in the vanadium back-extraction treatment is 5:1 to 1:1; wherein, the oil phase in the vanadium back-extraction treatment refers to the vanadium-loaded organic phase, including the extractant, extraction aid and diluent containing vanadium after extraction, and the aqueous phase in the vanadium back-extraction treatment refers to the back-extraction agent solution used in the vanadium back-extraction treatment, such as a strongly alkaline back-extraction agent.

[0087] For example, the volume ratio of the oil phase to the water phase in the vanadium back-extraction treatment is 5:1, 4:1, 3:1, 2:1, 1:1 or any value between 5:1 and 1:1.

[0088] The weakly basic stripping agent includes at least one of ammonia, ammonium carbonate solution, and ammonium bicarbonate solution, and the concentration of the weakly basic stripping agent is 0.3~3 mol / L; for example, the concentration of the weakly basic stripping agent is 0.3 mol / L, 0.5 mol / L, 1 mol / L, 2 mol / L, 3 mol / L, or any value between 0.3 and 3 mol / L.

[0089] The volume ratio of the oil phase to the water phase in the molybdenum back-extraction treatment is 5:1 to 1:1. For example, the volume ratio of the oil phase to the water phase in the molybdenum back-extraction treatment is 5:1, 4:1, 3:1, 2:1, 1:1 or any value between 5:1 and 1:1.

[0090] According to embodiments of this application, the alkaline substance includes at least one of sodium hydroxide, potassium hydroxide, and sodium carbonate;

[0091] The mass of the alkaline substance is 0.7 to 1.2 times the mass of the leaching residue; for example, the mass of the alkaline substance is any value between 0.7, 0.9, 1, 1.2 times, or 0.7 to 1.2 times the mass of the leaching residue.

[0092] The sintering temperature is 400℃~800℃; for example, the sintering temperature is 400℃, 500℃, 600℃, 700℃, 800℃ or any value between 400℃ and 800℃.

[0093] The sintering time is 0.5 to 3.0 hours. For example, the sintering time can be 0.5 hours, 1 hour, 2 hours, 3 hours, or any value between 0.5 and 3.0 hours.

[0094] According to embodiments of this application, the process used for the aluminum deposition treatment is a crystal separation process or a carbon separation process, and the aluminum-containing product includes at least one of aluminum hydroxide, alumina, and boehmite.

[0095] The crystallization process includes: transferring the filtrate into a reaction vessel, heating it to 60℃~90℃ with stirring, and holding it at that temperature for 2.0~6.0 hours; after the holding period ends, cooling it to room temperature, filtering and separating it to obtain an aluminum-containing product;

[0096] The carbon separation process includes: introducing CO2 into the filtrate at 40℃~70℃, monitoring the pH of the solution to be 9.5~11.0, and maintaining the temperature for 1.0~3.0h; after the temperature maintenance is completed, cooling to room temperature, filtering and separating to obtain an aluminum-containing product.

[0097] According to embodiments of this application, the mass of calcium oxide accounts for 10-30% of the mass of the water-leached residue; for example, the mass of calcium oxide accounts for any value between 10%, 20%, 30% or 10-30% of the mass of the water-leached residue.

[0098] The iron-containing substance includes iron concentrate;

[0099] The iron-containing substance accounts for 20-50% of the mass of the water-leached residue; for example, the iron-containing substance accounts for any value between 20%, 30%, 40%, 50% or 20-50% of the mass of the water-leached residue.

[0100] The reduction melting temperature is 1000-1300℃. For example, the reduction melting temperature is 1000℃, 1100℃, 1200℃, 1300℃ or any value between 1000-1300℃.

[0101] The method described in this application is for the efficient recovery and utilization of nickel and aluminum from water-leached slag, realizing the high-value utilization of all components of waste hydrogenation catalyst.

[0102] In some embodiments, the nickel content in the nickel-iron alloy product is 10-50%.

[0103] Depend on Figure 1 and Figure 2 It can be seen that in existing methods for recovering spent hydrogenation catalysts, the aluminum slag needs to be pressure-leached when recovering aluminum and nickel. Pressure leaching needs to be carried out in a high-pressure environment (2MPa), which places high demands on equipment, is costly, and carries significant operational risks. In contrast, the method in this application utilizes sintering and roasting to recover aluminum and nickel, and can be done using atmospheric pressure equipment. The equipment is simple, and the operation process is simplified.

[0104] The implementation schemes of this application will be described in detail below with reference to specific embodiments. However, those skilled in the art will understand that the following embodiments are only for illustrating this application and should not be regarded as limiting the scope of this application. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used without specified manufacturers are all conventional products that can be purchased commercially.

[0105] Example 1

[0106] Waste hydrogenation catalyst was used as raw material. The raw material composition is shown in Table 1. Figure 2 The process flow shown is used for comprehensive recycling.

[0107] Table 1. Composition of Waste Hydrogenation Catalyst

[0108]

[0109] 1) Waste hydrogenation catalyst was collected and mixed with 16% sodium carbonate (mass ratio of waste hydrogenation catalyst to sodium carbonate 100:16). Sodium calcination was performed in a fluidized bed roaster at 1150℃ in an oxygen-enriched air atmosphere with an oxygen excess coefficient of 1.5 for 2.0 hours. The resulting calcined precipitate contained 0.08% carbon and 0.13% sulfur, with removal rates of 99.6% and 98.6%, respectively. The sulfur dioxide concentration in the flue gas was 3%. A wet flue gas sulfuric acid production process was used, resulting in high sulfur resource utilization.

[0110] Selective water leaching of calcined sand yielded a vanadium-molybdenum-containing leachate. The leaching temperature was controlled at 70℃, the liquid-to-solid ratio at 2.5:1 mL / g, the pH at 8.76, and the leaching time at 1.5 h. The leaching rates of vanadium and molybdenum reached 96.8% and 97.3%, respectively.

[0111] 2) Extraction and separation were carried out on the vanadium-molybdenum-containing leachate. The extractant, extraction aid, and diluent were methyltrioctylammonium chloride, n-octanol, and No. 260 solvent oil, respectively, with a volume ratio of 20:10:70. The volume ratio of the oil phase to the water phase was 5:1, and the extraction time was 3 min, resulting in a vanadium-molybdenum-containing organic phase. The extraction rates of vanadium and molybdenum were 99.5% and 99.6%, respectively.

[0112] A vanadium-molybdenum-containing organic phase was mixed with a 2.5 mol / L sodium hydroxide solution at a 1:1 oil-to-water volume ratio and stirred for vanadium back-extraction, yielding a vanadium back-extraction solution and a molybdenum-containing organic phase. The molybdenum-containing organic phase was then mixed with a 2 mol / L ammonium bicarbonate solution at a 1:1 oil-to-water volume ratio and stirred for molybdenum back-extraction, yielding a molybdenum back-extraction solution. Subsequently, ammonium salt precipitation of vanadium was performed on the sodium vanadate solution, achieving a purity of 99.5% for ammonium metavanadate. Acidification precipitation of molybdenum was then performed on the ammonium molybdate solution to obtain a high-purity ammonium molybdate product with a purity of 99.5%.

[0113] 3) Sodium hydroxide was added to the leaching residue for sintering. The amount of sodium hydroxide added was 0.75 times that of the leaching residue. The sintering temperature was 450℃, and the calcination time was 1 hour. The resulting calcined residue was leached with water to obtain water-leached residue and filtrate. The filtrate was used to produce aluminum hydroxide using a carbon separation process: CO2 was slowly introduced into the aluminum-containing filtrate at 70℃, and the pH of the solution was monitored to be 9.5. The temperature was maintained for 3.0 hours. After the temperature maintenance was completed, the solution was cooled to room temperature, and aluminum hydroxide was separated by filtration. The aluminum recovery rate was 87.22%. The water-leached residue was used to produce ferronickel using a reduction smelting process. The water-leached residue was mixed with calcium oxide and iron concentrate, and then reduced and smelted. The mass of calcium oxide accounted for 20% of the mass of the water-leached residue, and the mass of iron concentrate accounted for 30% of the mass of the water-leached residue. The smelting temperature was 1200℃, and the time was 1 hour. The resulting ferronickel alloy product contained 35.33% nickel, and the nickel recovery rate during the smelting process was 98.6%.

[0114] Example 2

[0115] The difference between Example 2 and Example 1 is that in step 1), the sodium calcination temperature is 1000°C. The rest is the same as in Example 1.

[0116] In Example 2, the carbon and sulfur contents of the calcined sand obtained after roasting were 0.32% and 1.06%, respectively, with carbon and sulfur removal rates of 98.2% and 89.0%, respectively. Under unchanged water leaching conditions, the leaching rates of vanadium and molybdenum reached 95.7% and 95.9%, respectively.

[0117] Example 3

[0118] The difference between Example 3 and Example 1 is that in step 1), the sodium calcination temperature is 1250°C. The rest is the same as in Example 1.

[0119] In Example 3, the carbon and sulfur contents of the calcined sand obtained after roasting were 0.05% and 0.09%, respectively, and the removal rates of carbon and sulfur were 99.7% and 99.1%, respectively. Under the same water leaching conditions, the leaching rates of vanadium and molybdenum reached 98.7% and 99.6%, respectively.

[0120] Example 4

[0121] The difference between Example 4 and Example 1 is that in step 2), the volume ratio of the extracted oil phase to the water phase is 1:2.

[0122] In Example 4, the extraction rates of vanadium and molybdenum were 81.2% and 75.6%, respectively.

[0123] Example 5

[0124] The difference between Example 5 and Example 1 is that in step 1), the sodium calcination temperature is 800°C. The rest is the same as in Example 1.

[0125] In Example 5, the carbon and sulfur contents in the calcined sand were 0.56% and 3.51%, respectively, and the removal rates of carbon and sulfur were 96.9% and 63.5%, respectively. Under the same water leaching conditions, the leaching rates of vanadium and molybdenum reached 91.1% and 92.6%, respectively.

[0126] The sodium roasting temperatures in Examples 1-3 and Example 5 are different. The leaching rates of vanadium and molybdenum in Example 5 are lower than those in Examples 1-3, indicating that the sodium roasting temperature in step 1) is preferably 1000℃~1250℃.

[0127] Comparative Example 1

[0128] The raw material composition of the waste hydrogenation catalyst used in Comparative Example 1 is the same as that in Example 1.

[0129] Comparative Example 1: The waste hydrogenation catalyst was comprehensively recovered using the traditional process flow of "de-oiling-sodium roasting-water leaching-ammonium salt precipitation of vanadium-acidification precipitation of molybdenum".

[0130] 1) Vacuum deoiling is used for the waste hydrogenation catalyst, followed by the addition of sodium carbonate and grinding. The amount of sodium carbonate added is 28% (the mass ratio of waste hydrogenation catalyst without vacuum deoiling to sodium carbonate is 100:28), and the grinding particle size is -200 mesh, accounting for 80%.

[0131] 2) The crushed and ground material was subjected to sodium roasting at 800℃ for 2 hours. The roasted sand obtained after roasting was selectively leached in water to obtain a vanadium-molybdenum leachate. The leaching temperature was controlled at 70℃, the liquid-to-solid ratio at 2.5, and the pH at 8.76. The leaching rates of vanadium and molybdenum reached 91.89% and 92.32%, respectively.

[0132] 3) For the vanadium-molybdenum leaching solution, vanadium was first precipitated with ammonium sulfate at an excess ratio of 1.2. The precipitation temperature was room temperature, and the precipitation time was 1 hour. The vanadium precipitation rate was 98%, and the molybdenum entrainment was 1%. The purity of the resulting ammonium metavanadate product was 98%. After vanadium precipitation, the solution was acidified to precipitate molybdenum, with a molybdenum precipitation rate of 90%. The tailings were treated with resin adsorption to remove molybdenum, with a total recovery rate of approximately 97%. The purity of the molybdic acid product was 95%.

[0133] 4) Water-leached residue is either subjected to pressurized alkaline leaching or sold directly as secondary hazardous waste, resulting in low resource utilization efficiency.

[0134] Compared to the examples, Comparative Example 1 exhibits lower vanadium and molybdenum leaching rates, and lower purity in the vanadium-containing and molybdenum-containing products. Furthermore, the examples also achieve aluminum and nickel recovery with higher aluminum and nickel recovery rates. This demonstrates that Comparative Example 1 is inferior to the examples.

[0135] Comparative Example 2

[0136] The raw material composition of the waste hydrogenation catalyst used in Comparative Example 2 is the same as that in Example 1.

[0137] Comparative Example 2 uses the traditional process of "de-oiling-sodium roasting-water leaching-ammonium salt precipitation of vanadium-acidification precipitation of molybdenum" to comprehensively recover the waste hydrogenation catalyst.

[0138] 1) Vacuum deoiling is used for waste hydrogenation catalyst, followed by the addition of sodium carbonate and grinding. The amount of sodium carbonate added is 30% (the mass ratio of waste hydrogenation catalyst without vacuum deoiling to sodium carbonate is 100:30), and the grinding particle size is -200 mesh, accounting for 80%.

[0139] 2) After crushing and grinding, the material is subjected to sodium roasting in a rotary kiln at a temperature of 800℃ for 2 hours. The sulfur removal rate during the roasting process is only 53%, and the remaining 47% of the sulfur is converted into sodium sulfate in the roasted sand, resulting in a sulfur dioxide concentration of only 1% in the flue gas. It cannot be used for acid production and can only be desulfurized by gypsum, resulting in low resource utilization.

[0140] The sulfur dioxide concentration in the flue gas of Comparative Example 2 was lower than that of the Example 1. The flue gas of the Example 1 could be used for acid production, demonstrating high sulfur resource utilization. However, the flue gas of Comparative Example 2 could not be used for acid production. This indicates that Comparative Example 2 was less effective than the Example 1.

[0141] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0142] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the foregoing claims, any of the claimed embodiments can be used in any combination. The information disclosed in this background section is intended only to enhance the understanding of the general background of this application and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

Claims

1. A method for short-process full-component gradient recovery of spent hydrogenation catalyst, characterized in that, The application relates to a method for extracting vanadium and molybdenum from waste hydrogenation catalysts. The waste hydrogenation catalyst is mixed with sodium carbonate, and is calcined in a suspension boiling calciner to obtain a calcined product; The calcined product is leached with water, and after solid-liquid separation, a leaching solution and a leaching residue are obtained; The leaching solution is extracted with an extractant, and a vanadium-molybdenum-containing organic phase and a raffinate are separated; the vanadium-molybdenum-containing organic phase is treated with a strong alkaline back-extracting agent and a weak alkaline back-extracting agent in sequence to obtain a vanadium back-extracting solution and a molybdenum back-extracting solution; the vanadium back-extracting solution is mixed with an ammonium salt to carry out vanadium precipitation treatment, and ammonium metavanadate is obtained; the molybdenum back-extracting solution is acidified to carry out molybdenum precipitation, and ammonium molybdate is obtained; The leaching residue is sintered with an alkaline substance, and the obtained calcine is leached with water to obtain a water leaching residue and a filtrate; the filtrate is treated to carry out aluminum precipitation, and an aluminum-containing product is obtained; the water leaching residue is mixed with calcium oxide and an iron-containing substance to carry out reduction smelting, and a nickel-iron alloy is obtained; The calcining temperature is 1000 DEG C to 1250 DEG C, the calcining atmosphere is a strong oxidizing atmosphere, the oxygen excess coefficient of the strong oxidizing atmosphere is 1.2 to 1.5, and the calcining time is 0.5 to 6.0 h; The strong alkaline back-extracting agent is a sodium hydroxide solution, the concentration of the strong alkaline back-extracting agent is 0.3 to 3 mol / L, the weak alkaline back-extracting agent is an ammonium bicarbonate solution, and the concentration of the weak alkaline back-extracting agent is 0.3 to 3 mol / L.

2. The method for total component cascade recovery of spent hydrogenation catalyst short process according to claim 1, characterized in that, The waste hydrogenation catalyst contains 1 to 16 wt% of V, 2 to 10 wt% of Mo, 1 to 6 wt% of Ni, 18 to 40 wt% of Al2O3, 8 to 15 wt% of S, 10 to 20 wt% of difficult-to-volatilize carbon, and 5 to 20 wt% of volatile hydrocarbon compounds, wherein the volatile hydrocarbon compounds contain hydrocarbon compounds and derivatives of the hydrocarbon compounds, and the derivatives of the hydrocarbon compounds contain nitrogen-containing hydrocarbon compounds.

3. The method for total component cascade recovery of spent hydrogenation catalyst short course according to claim 1, characterized in that, The mass ratio of the waste hydrogenation catalyst to sodium carbonate is 100:(5 to 20). The calcining process also produces flue gas, and the concentration of sulfur dioxide in the flue gas is 2.8 to 3.2%.

4. The method for total component cascade recovery of spent hydrogenation catalyst short course according to claim 1, characterized in that, When the calcined product is leached with water, the solid-liquid ratio of the leaching solution is (1.5 to 5.0):1 mL / g, the leaching temperature is 10 DEG C to 95 DEG C, and the leaching time is 0.3 to 3.0 h.

5. The method for total component cascade recovery of spent hydrogenation catalyst short course according to claim 1, characterized in that, The extractant contains a quaternary ammonium salt anion extractant, and the quaternary ammonium salt anion extractant contains at least one of methyltrioctylammonium chloride, trioctylmethylammonium bromide and tetrabutylammonium bromide. When the extraction is performed, the method further comprises adding an auxiliary extraction agent and a diluent to the extraction agent, the auxiliary extraction agent comprising at least one of n-octanol, iso-octanol and sec-octanol, the diluent comprising at least one of sulfonated kerosene and No. 260 solvent oil; the volume ratio of the extraction agent to the auxiliary extraction agent to the diluent being (15-35%):(5-15%):(50-80%); The volume ratio of the extracted oil phase to the water phase is 5:1-1:

2.

6. The method for total component grade recycling of spent hydrogenation catalyst short process according to claim 1, characterized in that, The volume ratio of the stripped vanadium-treated oil phase to the water phase is 5:1-1:

1.

7. The method for total component cascade recovery of spent hydrogenation catalyst short course according to claim 1, characterized in that, The volume ratio of the stripped molybdenum-treated oil phase to the water phase is 5:1-1:

1.

8. The method for total component cascade recovery of spent hydrogenation catalyst short course according to claim 1, characterized in that, The basic substance comprises at least one of sodium hydroxide, potassium hydroxide and sodium carbonate; The mass of the basic substance is 0.7-1.2 times the mass of the leaching residue; The sintering treatment temperature is 400-800℃; The sintering treatment time is 0.5-3.0h.

9. The process for total components cascade recovery from spent hydrogenation catalyst according to any one of claims 1-8, characterized by that, The mass of the calcium oxide is 10-30% of the mass of the water leaching residue; The iron-containing substance comprises iron concentrate powder; The mass of the iron-containing substance is 20-50% of the mass of the water leaching residue; The reduction smelting temperature is 1000-1300℃.

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