CN114075623B - Resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst - Google Patents

Abstract

The invention provides a resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalysts. Belongs to the technical field of metallurgy. The method comprises the following steps: deoiling, first-stage dissolution, crystallization, second-stage dissolution, crystallization and separation. The invention adopts a two-stage dissolution process to realize the separation and recovery of vanadium, molybdenum, nickel, cobalt and aluminum, and the dissolution rate of vanadium is 90-97%, the dissolution rate of molybdenum is 95-98%, the dissolution rate of cobalt is 50-60% and the dissolution rate of aluminum is 85-90%. The grade of cobalt in the cobalt-rich slag can reach 30 percent, the grade of nickel in the nickel-rich slag can reach more than 15 percent, and the obtained hydrated sodium aluminate with the purity of 60-80 percent can be used as an intermediate material for producing aluminum hydroxide, thereby realizing the resource utilization of the vanadium-containing waste petroleum catalyst; the invention adopts a hydrometallurgy flow, has mild process and can realize the circulation of the medium.

Description

Resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst

Technical Field

The invention belongs to the technical field of metallurgy, and particularly relates to a resource utilization method for two-stage extraction of a vanadium-containing waste petroleum catalyst.

Background

In modern industrial production, the role of the catalyst is more and more important, and the catalyst is widely applied to the oil refining industry, the chemical industry and the metallurgical industry. The spent catalyst is produced by about 50-70 ten thousand tons all over the world, wherein the vanadium content is very high, and part of the catalyst also contains a certain amount of cobalt, aluminum, nickel, molybdenum and the like, so the metal recovery in the catalyst is significant from the two aspects of resource utilization and environmental protection.

Hydrodesulfurization (HDS) catalysts are widely used in the petroleum refining and chemical industries today, and the components of HDS catalysts mainly include: molybdenum, cobalt and a carrier alumina. During use, the deposition of vanadium and nickel metals from the feedstock can gradually deactivate the HDS catalyst, resulting in the emission of large quantities of spent catalyst, which can cause environmental pollution and loss of some useful metals.

CN105274344A discloses a method for recovering vanadium and molybdenum from waste petroleum catalysts, which realizes the recovery of vanadium and molybdenum metals in the waste petroleum catalysts through the processes of empty burning, ball-removing, ball-milling, soda roasting, water leaching, aluminum removal, vanadium precipitation and molybdenum ion exchange enrichment.

CN111321296A discloses a method for recovering vanadium and nickel from waste petroleum catalyst, which extracts vanadium and nickel metals from the waste petroleum catalyst through the steps of roasting, vacuum volatilization, dissolving and purifying and the like. The method for recovering vanadium and nickel from the waste petroleum catalyst provided by the invention utilizes the difference of saturated vapor pressure of each component in the waste catalyst under different temperature conditions to carry out vacuum separation, and the component is easier to volatilize when the saturated vapor pressure of the component is higher at the same temperature. Controlling certain temperature and vacuum degree, leading the component with large steam pressure to preferentially volatilize and the component with small steam pressure to remain in the slag, thereby realizing the purpose of separating certain component. At present, vacuum volatilization is mostly used in a binary metal system and is relatively easy to realize, but is not applied to a system in which a waste catalyst contains multiple metals such as vanadium, aluminum, nickel, molybdenum and the like, and the control difficulty is high. In order to avoid mutual interference among the components and improve the direct yield and the product quality, the invention needs unique equipment design besides controlling the temperature and the vacuum degree to achieve the optimal matching of all conditions and realize the step-by-step recovery of all metal components, the required conditions are harsh, the process is complicated, and only two metals of vanadium and nickel can be recovered.

The recovery method in the scheme has the problems of long flow, high cost, low recovery rate of valuable metals and waste in the recovery process. Therefore, it is necessary to develop a method for recycling vanadium-containing waste petroleum catalysts, which has the advantages of high recovery rate of effective components, low cost, simple process flow, recyclable media and capability of recovering various metals.

Disclosure of Invention

The invention aims to provide a resource utilization method for two-stage extraction of a vanadium-containing waste petroleum catalyst, in particular to a novel method for pretreating vanadium extraction tailings of the vanadium-containing waste petroleum catalyst by a low-temperature high-alkali system with industrial operability, so as to solve the defect that the vanadium extraction tailings of the multi-component vanadium-containing waste petroleum catalyst cannot be comprehensively utilized.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst, which comprises the following steps:

(1) First-stage dissolution: mixing the deoiled vanadium-containing waste petroleum catalyst with a first alkali liquor, and carrying out a dissolution reaction to obtain an alkali solution containing vanadate and molybdate and residues;

(2) Secondary dissolution: mixing the residue obtained in step (1) with a second alkaline solution, and performing dissolution reaction at a temperature of 200 deg.C or higher, such as 200 deg.C, 210 deg.C, 220 deg.C, 230 deg.C, 240 deg.C, 250 deg.C or 260 deg.C, to obtain an alkaline solution containing cobaltate and aluminate and a nickel-rich residue.

The two-stage extraction and resource utilization method of the vanadium-containing waste petroleum catalyst adopts a two-stage dissolution process, vanadium and molybdenum are separated and recovered in the first stage, and cobalt and aluminum are further dissolved out in the second stage by adjusting factors such as dissolution temperature, pressure and the like, so that the separation and recovery of various metal elements are realized. Compared with the first-stage extraction, the method has the advantages that the separation of multiple elements in the system is easier to realize through independent regulation, vanadium and molybdenum can be separated independently in a low-alkali area, aluminum and cobalt can be separated independently in a high-alkali area, and the reaction media of two stages are self-circulated, so that the complicated separation procedures when multiple elements coexist are reduced.

Preferably, the primary dissolution pressure in the step (1) is normal pressure.

Preferably, the dissolution temperature in the step (1) is 60 to 100 ℃, for example, 60 ℃, 70 ℃, 80 ℃, 90 ℃ or 100 ℃.

According to the invention, the first-stage dissolution temperature is adopted, the deoiled vanadium-containing waste petroleum catalyst is mixed with the first alkali liquor, and dissolution is carried out under the normal pressure condition, so that the dissolution of vanadium and molybdenum is facilitated, the dissolution rate of vanadium and molybdenum is improved, when the first-stage dissolution temperature is lower than 60 ℃, the co-dissolution of aluminum can be caused when the first-stage dissolution temperature is higher than 100 ℃, and the selective dissolution of vanadium and molybdenum can not be realized.

Preferably, the time of the dissolution reaction in the step (1) is 30 to 120min, such as 30min, 40min, 50min, 60min, 70min, 80min, 90min, 100min, 110min or 120min.

Preferably, the first alkali solution in step (1) is sodium hydroxide solution.

Preferably, the first alkali solution used in the dissolution reaction in the step (1) has a mass concentration of 10% to 40%, for example, 10%, 15%, 20%, 25%, 30%, 35%, or 40%.

The alkali mass concentration of the first-stage dissolution reaction is limited to be within the range, so that the dissolution of vanadium and molybdenum is facilitated, and the dissolution rate is improved.

Preferably, in the step (2), the ratio of the mass of the alkali in the second alkaline solution to the mass of the residue is 1.5 to 3, for example, 1.5.

In the present invention, the ratio of the mass of the alkali to the mass of the residue in the secondary dissolution is limited to the above range, which is advantageous for sufficient dissolution of cobalt and aluminum and improves the dissolution rate.

Preferably, the second alkali solution in step (2) is sodium hydroxide solution.

Preferably, the mass concentration of the second alkali solution in the step (2) is 50 to 70%, such as 50%, 55%, 60%, 65%, 70% or the like.

The mass concentration of the second alkali liquor is limited within the range, so that the dissolution of aluminum and cobalt is facilitated, and the dissolution rate is improved.

Preferably, the time for the dissolution reaction in the step (2) is 1 to 6 hours, for example, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, or 6 hours.

Preferably, the pressure of the secondary dissolution in the step (2) is 0.3 to 1MPa, such as 0.4MPa, 0.5MPa, 0.6MPa, 0.7MPa, 0.8MPa or 0.9 MPa.

The pressure in the secondary dissolution is more than or equal to 0.2Mpa, and more preferably 0.3-1 Mpa.

Preferably, the step (2) further comprises washing the residue with water before mixing the residue with the second alkaline solution.

Preferably, the step (2) further comprises washing the nickel-rich slag with water.

Preferably, the water washing includes a primary water washing and a secondary water washing.

Preferably, the detergent for the primary water washing and/or the secondary water washing is water.

Preferably, the washing liquid obtained by the secondary washing is used as a detergent for the primary washing.

Preferably, the deoiling method in the step (1) comprises the step of subjecting the vanadium-containing waste petroleum catalyst to combustion treatment.

Preferably, the temperature of the combustion treatment is 500 to 600 ℃, for example 500 ℃, 510 ℃, 520 ℃, 530 ℃, 540 ℃, 550 ℃, 560 ℃, 570 ℃, 580 ℃, 590 ℃, 600 ℃ or the like.

The invention carries out deoiling treatment on the vanadium-containing waste petroleum catalyst to remove organic matters containing carbon and sulfur.

Preferably, the resource utilization method further comprises the step of cooling and crystallizing the alkali solution containing vanadate and molybdate obtained in the step (1) to obtain mixed crystals of vanadate and molybdate.

Preferably, the temperature of the temperature-reducing crystallization is reduced to 25 to 45 ℃, such as 25 ℃, 27 ℃, 29 ℃, 31 ℃, 33 ℃, 35 ℃, 37 ℃, 39 ℃, 41 ℃, 43 ℃ or 45 ℃ and the like.

The crystallization is carried out at the temperature, so that the mixed crystals of vanadate and molybdate can be effectively separated from the solution, and the required vanadate and molybdate crystals can be furthest crystallized before other impurities are not separated out.

Preferably, the resource utilization method further comprises the steps of dissolving the mixed crystal of vanadate and molybdate with water to obtain a vanadium-containing solution, adjusting the pH value, and adding ammonium salt to obtain ammonium metavanadate and a vanadium precipitation mother solution.

Preferably, the adjusted pH is 7.9 to 8.1, such as 7.9, 7.95, 8.0, 8.05 or 8.1, etc.

The invention can completely dissolve the mixed crystal of vanadate and molybdate at the pH value and does not separate out molybdic acid precipitate.

Preferably, the method of adjusting the pH comprises adding sulfuric acid.

Preferably, the ammonium salt comprises ammonium sulfate and/or ammonium chloride.

Preferably, the resource utilization method further comprises the steps of carrying out ion exchange adsorption on the vanadium precipitation mother liquor, and resolving by using sodium hydroxide to obtain a resolving solution.

Preferably, the resolving solution is used for adjusting the pH of the vanadium-containing solution.

Preferably, the resource utilization method further comprises the steps of extracting the vanadium precipitation mother liquor or the vanadium precipitation mother liquor subjected to ion exchange adsorption by using N263, and adjusting the pH value to obtain molybdic acid precipitate;

preferably, the resource utilization method further comprises the step of standing and aging the alkali liquor containing the cobaltate and the aluminate or adding an oxidant to obtain the alkali liquor containing the cobaltate and the cobalt-rich slag.

Preferably, when the mass concentration of the alkali liquor containing the cobaltate and the aluminate is less than 300g/L, a standing aging method is adopted to obtain the alkali liquor containing the aluminate and cobalt-rich slag.

Preferably, when the mass concentration of the alkali liquor containing cobaltate and aluminate is more than or equal to 300g/L, adding an oxidant to obtain an alkali liquor containing the cobaltate and cobalt-rich slag.

Preferably, the oxidizing agent comprises hydrogen peroxide and/or sodium peroxide.

Preferably, the resource utilization method further comprises the steps of concentrating the alkaline solution containing the aluminate, cooling and crystallizing to obtain aluminate crystals and crystallization mother liquor.

Preferably, the concentration is terminated until the mass concentration of the alkali liquor in the solution is 650-900 g/L, such as 650g/L, 700g/L, 750g/L, 800g/L, 850g/L or 900g/L, etc., preferably 680g/L.

The method can maximally precipitate aluminate contained in the solution by concentrating the aluminate-containing alkali solution to the mass concentration, and facilitates the circulation of the subsequent crystallization mother solution to the secondary dissolution process for the dissolution of cobalt and aluminum, thereby realizing the recycling of the dissolution medium.

Preferably, the resource utilization method further comprises mixing the crystallization mother liquor with a second alkali liquor for the dissolution reaction in the step (2).

As a preferred technical scheme, the two-stage extraction and resource utilization method of the vanadium-containing waste petroleum catalyst comprises the following steps:

(a) Deoiling: burning the vanadium-containing waste petroleum catalyst at 500-600 ℃;

(b) First-stage dissolution: mixing the deoiled vanadium-containing waste petroleum catalyst in the step (a) with a sodium hydroxide solution, and carrying out a dissolution reaction for 30-120 min under the conditions that the pressure is normal pressure, the temperature is 60-100 ℃, and the mass concentration of alkali liquor is 10-40% to obtain alkali solution and residue containing sodium vanadate and sodium molybdate;

(c) Vanadium molybdenum crystallization: cooling the alkali solution containing sodium vanadate and sodium molybdate in the step (b) to 25-45 ℃ for crystallization to obtain mixed crystals of sodium vanadate and sodium molybdate;

(d) And (3) separating vanadium: dissolving the mixed crystal of sodium vanadate and sodium molybdate in the step (c) to obtain a vanadium-containing solution, adjusting the pH to 7.9-8.1, adding ammonium sulfate and/or ammonium chloride, precipitating to generate ammonium metavanadate and vanadium precipitation mother liquor, carrying out ion exchange adsorption on the vanadium precipitation mother liquor, and analyzing sodium hydroxide to obtain an analysis solution for adjusting the pH of the vanadium-containing solution;

(e) Separating molybdenum: extracting the vanadium precipitation mother liquor subjected to ion exchange adsorption, and adjusting the pH value to obtain molybdic acid precipitate;

(f) Secondary dissolution: mixing the residue obtained in the step (b) with a sodium hydroxide solution with the mass concentration of 50-70%, wherein the mass ratio of the sodium hydroxide to the residue is 1.5-3, and carrying out a dissolution reaction under the conditions that the pressure is 0.3-1 MPa and the temperature is more than or equal to 200 ℃ to obtain an alkali liquor containing cobaltate and aluminate and a nickel-rich residue;

(g) Separating cobalt: standing and aging the alkali liquor containing sodium cobaltate and sodium aluminate or adding an oxidant to obtain an alkali solution containing sodium aluminate and cobalt-rich slag;

(h) Separating aluminum: concentrating an alkali solution containing sodium aluminate, cooling and crystallizing to obtain sodium aluminate crystals and a crystallization mother liquor; the crystallization mother liquor is returned to the step (f) for secondary dissolution.

Compared with the prior art, the invention has the following beneficial effects:

(1) The invention adopts two-stage dissolution, and effectively realizes the separation and recovery of vanadium, molybdenum, nickel, cobalt and aluminum.

(2) In the two-stage dissolution, the dissolution rate of vanadium in the first-stage dissolution is 90-97%, and the dissolution rate of molybdenum is 95-98%; the leaching rate of cobalt in the secondary leaching is 50-60%, the leaching rate of aluminum is 85-90%, and the grade of nickel in the nickel-rich slag can reach more than 15%.

(3) The invention adopts the flow of hydrometallurgy, and the process is mild.

Drawings

FIG. 1 is a flow chart of the two-stage extraction resource utilization method of the vanadium-containing waste petroleum catalyst provided by the invention.

Detailed Description

The technical solution of the present invention is further explained by the following embodiments. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

The invention is further illustrated by the following examples in conjunction with the accompanying drawings.

The flow schematic diagram of the two-stage extraction resource utilization method of the vanadium-containing waste petroleum catalyst is shown in figure 1, and as can be seen from figure 1, the resource utilization method comprises the following steps:

(a) Deoiling: carrying out combustion treatment on the vanadium-containing waste petroleum catalyst;

(b) First-stage dissolution: mixing the deoiled vanadium-containing waste petroleum catalyst in the step (a) with a sodium hydroxide solution, carrying out a dissolution reaction for 30-120 min under the conditions that the pressure is normal pressure, the temperature is 60-100 ℃, and the mass concentration of alkali liquor is 10-40%, and carrying out liquid-solid separation to obtain alkali solution (dissolution liquid) containing sodium vanadate and sodium molybdate and residue (No. 1 tailings);

(c) Vanadium molybdenum crystallization: cooling the alkali solution containing sodium vanadate and sodium molybdate in the step (b) to 25-45 ℃ for crystallization to obtain mixed crystals of sodium vanadate and sodium molybdate and crystallization mother liquor, wherein the crystallization mother liquor is used for primary dissolution;

(d) And (3) separating vanadium: dissolving the mixed crystal of sodium vanadate and sodium molybdate in the step (c) to obtain a vanadium-containing solution, adjusting the pH to 7.9-8.1, adding ammonium sulfate and/or ammonium chloride, and precipitating to generate ammonium metavanadate and a vanadium precipitation mother solution;

(e) And (3) molybdenum separation: extracting the vanadium precipitation mother liquor, and adjusting the pH value (back extraction) to obtain molybdic acid precipitate;

(f) Secondary dissolution: washing the residue obtained in the step (b) with water, mixing the washed residue with a sodium hydroxide solution with the mass concentration of 50-70%, wherein the mass ratio of the sodium hydroxide to the residue is 1.5-3;

(g) Separating cobalt: standing and aging the alkali liquor containing cobaltate and aluminate or adding an oxidant to resolve cobalt to obtain an alkali solution containing the cobaltate and cobalt-rich slag;

(h) Separating aluminum: concentrating the alkaline solution containing aluminate, cooling, crystallizing, and performing liquid-solid separation to obtain aluminate crystals and crystallized mother liquor, wherein the crystallized mother liquor is used for secondary dissolution.

The main components of the used catalysts obtained by burning and deoiling the vanadium-containing used petroleum catalysts used in the following examples and comparative examples are shown in table 1:

TABLE 1 elemental composition/wt% of spent catalyst

	Al	Ca	Co	Fe	Mg	Mo	Ni	P	Si	V	C	S
													Catalyst and process for producing the same	22.66	0.40	0.63	0.95	0.28	7.38	3.67	0.74	2.15	7.64	0.29	1.89

Example 1

A resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst comprises the following steps:

(a) First-stage dissolution: weighing 100g of the deoiled waste catalyst, mixing with a sodium hydroxide solution with the mass concentration of 40%, adding into a reaction kettle together, and carrying out dissolution at the temperature of 100 ℃, for 30min and under the normal pressure; obtaining a dissolution liquid and residues; wherein the dissolution rate of vanadium is 95.2 percent, and the dissolution rate of molybdenum is 96.1 percent;

(b) Vanadium molybdenum crystallization: cooling the dissolution liquid obtained in the step (a) to 45 ℃ for crystallization, and performing vacuum filtration separation to obtain mixed crystals containing sodium vanadate and sodium molybdate;

(c) And (3) separating vanadium: dissolving the mixed crystal obtained in the step (b) by hot water to obtain vanadium-containing liquid, adjusting the pH value to 8 by sulfuric acid, adding ammonium sulfate to precipitate most of vanadium, and generating ammonium metavanadate and vanadium precipitation mother liquor; the purity of the obtained sodium metavanadate is 98.2 percent;

(d) Separating molybdenum: extracting the vanadium precipitation mother liquor obtained in the step (c) by adopting N263, and then adjusting the pH value to obtain a molybdic acid precipitate; the molybdic acid has a purity of 98.8%;

(e) Secondary dissolution: mixing the residue obtained in the step (a) with a sodium hydroxide solution, wherein the addition amount of sodium hydroxide is 3 times of the mass of the residue, the mass concentration of the sodium hydroxide solution is 70%, the dissolution temperature is 260 ℃, the pressure is 1MPa, and the dissolution time is 2h; wherein, the dissolution rate of cobalt is 60 percent, and the dissolution rate of aluminum is 89.3 percent; diluting to alkali mass concentration of 250g/L, and filtering to obtain nickel-rich slag and a leaching solution, wherein the nickel content in the nickel-rich slag is 15.1%;

(f) Separating cobalt: standing the dissolved liquid obtained in the step (e) for 10 hours to obtain cobalt hydroxide precipitate, and filtering to obtain cobalt-rich slag and a sodium aluminate solution, wherein the cobalt-rich slag contains 28% of cobalt;

(g) Separating aluminum: evaporating and concentrating the sodium aluminate solution obtained in the step (f) to 680g/L, cooling to 80 ℃ for sodium aluminate crystallization, and performing liquid-solid separation to obtain sodium aluminate crystals and crystallization mother liquor; the purity of the sodium aluminate obtained was 83.7%.

Example 2

A resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst comprises the following steps:

(a) First-stage dissolution: weighing 100g of the deoiled waste catalyst, mixing with a 30% sodium hydroxide solution, adding into a reaction kettle together, and dissolving at 80 ℃, 60min and normal pressure; obtaining a dissolution liquid and residues; wherein the dissolution rate of vanadium is 93.5 percent, and the dissolution rate of molybdenum is 95.2 percent;

(b) Vanadium molybdenum crystallization: cooling the dissolution liquid obtained in the step (a) to 40 ℃ for crystallization, and performing vacuum filtration separation to obtain mixed crystals containing sodium vanadate and sodium molybdate;

(c) And (3) separating vanadium: dissolving the mixed crystal obtained in the step (b) by hot water to obtain vanadium-containing liquid, adjusting the pH value to 8 by sulfuric acid, adding ammonium sulfate to precipitate most of vanadium, and generating ammonium metavanadate and vanadium precipitation mother liquor; the purity of the obtained sodium metavanadate is 98.4 percent;

(d) And (3) molybdenum separation: extracting the vanadium precipitation mother liquor obtained in the step (c) by adopting N263, and then adjusting the pH value to obtain a molybdic acid precipitate; the molybdic acid has a purity of 98.9%;

(e) Secondary dissolution: mixing the residue obtained in the step (a) with a sodium hydroxide solution, wherein the addition amount of the sodium hydroxide is 3 times of the mass of the residue, the mass concentration of the sodium hydroxide solution is 60%, the dissolution temperature is 240 ℃, the pressure is 0.8MPa, and the dissolution time is 3h. The dissolution rate of cobalt is 58.6%, and the dissolution rate of aluminum is 87.2%. Diluting to alkali mass concentration of 350g/L, and filtering to obtain nickel-rich slag and a leaching solution, wherein the nickel content of the nickel-rich slag is 14.1%;

(f) Separating cobalt: adding hydrogen peroxide into the dissolution liquid obtained in the step (e) according to 0.1 percent of the dissolution liquid to obtain cobalt hydroxide precipitate, and filtering to obtain cobalt-rich slag and a sodium aluminate solution, wherein the cobalt-rich slag contains 27.6 percent of cobalt;

(g) Separating aluminum: and (f) evaporating and concentrating the sodium aluminate solution obtained in the step (f) to 700g/L, cooling to 80 ℃ for sodium aluminate crystallization, and performing liquid-solid separation to obtain sodium aluminate crystals and crystallization mother liquor, wherein the purity of the obtained sodium aluminate is 82.7%.

Example 3

A resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst comprises the following steps:

(a) First-stage dissolution: weighing 100g of the deoiled waste catalyst, mixing with a sodium hydroxide solution with the mass concentration of 20%, adding into a reaction kettle together, and carrying out dissolution at the temperature of 60 ℃, for 120min and under normal pressure; obtaining a dissolution liquid and residues. Wherein the dissolution rate of vanadium is 93.2 percent, and the dissolution rate of molybdenum is 95.1 percent;

(b) Vanadium molybdenum crystallization: cooling the dissolution liquid obtained in the step (a) to 45 ℃ for crystallization, and performing vacuum filtration separation to obtain mixed crystals containing sodium vanadate and sodium molybdate;

(c) Separating vanadium: dissolving the mixed crystal obtained in the step (b) by hot water to obtain vanadium-containing liquid, adjusting the pH value to 8 by sulfuric acid, adding ammonium sulfate to precipitate most of vanadium, and generating ammonium metavanadate and vanadium precipitation mother liquor; the purity of the obtained sodium metavanadate is 98.5 percent;

(d) And (3) molybdenum separation: extracting the vanadium precipitation mother liquor obtained in the step (c) by adopting N263, and then adjusting the pH value to obtain molybdenum acid precipitate, wherein the purity of the obtained molybdic acid is 98.6%;

(e) Secondary dissolution: mixing the residue obtained in the step (a) with a sodium hydroxide solution, wherein the addition amount of the sodium hydroxide is 2 times of the mass of the residue, the mass concentration of the sodium hydroxide solution is 50%, the dissolution temperature is 220 ℃, the pressure is 0.6MPa, and the dissolution time is 2h. Wherein, the dissolution rate of cobalt is 54.6 percent, and the dissolution rate of aluminum is 83.3 percent. Diluting to alkali mass concentration of 280g/L, and filtering to obtain nickel-rich slag and a leaching solution, wherein nickel in the nickel-rich slag is 12.6%;

(f) Separating cobalt: standing the dissolving liquid obtained in the step (e) for 12 hours to obtain cobalt hydroxide precipitate, and filtering to obtain cobalt-rich slag and a sodium aluminate solution, wherein the cobalt content of the obtained cobalt-rich slag is 26.7%;

(g) Separating aluminum: and (f) evaporating and concentrating the sodium aluminate solution obtained in the step (f) to 680g/L, cooling to 80 ℃ for sodium aluminate crystallization, and performing liquid-solid separation to obtain sodium aluminate crystals and crystallization mother liquor, wherein the purity of the obtained sodium aluminate is 81.6%.

Example 4

A resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst comprises the following steps:

(a) First-stage dissolution: weighing 100g of the deoiled waste catalyst, mixing with 10% sodium hydroxide by mass concentration, adding into a reaction kettle together, and carrying out dissolution at 70 ℃, for 120min and under normal pressure; obtaining a dissolution liquid and residues. Wherein the dissolution rate of vanadium is 93.2 percent, and the dissolution rate of molybdenum is 95.1 percent;

(b) Vanadium molybdenum crystallization: cooling the dissolution liquid obtained in the step (a) to 45 ℃ for crystallization, and performing vacuum filtration separation to obtain mixed crystals containing sodium vanadate and sodium molybdate;

(c) And (3) separating vanadium: dissolving the mixed crystal obtained in the step (b) by hot water to obtain vanadium-containing liquid, adjusting the pH value to 8 by sulfuric acid, adding ammonium sulfate to precipitate most of vanadium, and generating ammonium metavanadate and vanadium precipitation mother liquor; the purity of the obtained sodium metavanadate is 98.5 percent;

(d) And (3) molybdenum separation: extracting the vanadium precipitation mother liquor obtained in the step (c) by adopting N263, and then adjusting the pH value to obtain a molybdic acid precipitate; the molybdic acid has a purity of 98.6%;

(e) Secondary dissolution: mixing the residue obtained in the step (a) with a sodium hydroxide solution, wherein the addition amount of the sodium hydroxide is 1.5 times of the mass of the residue, the mass concentration of the sodium hydroxide solution is 70%, the dissolution temperature is 260 ℃, the pressure is 1MPa, and the dissolution time is 2h. The dissolution rate of cobalt is 58.7%, and the dissolution rate of aluminum is 88.3%. Diluting to alkali mass concentration of 250g/L, and filtering to obtain nickel-rich slag and a leaching solution, wherein 13.9% of nickel is contained in the nickel-rich slag;

(f) Separating cobalt: standing the dissolution liquid obtained in the step (e) for 10 hours to obtain cobalt hydroxide precipitate, and filtering to obtain cobalt-rich slag and a sodium aluminate solution, wherein the cobalt content of the cobalt-rich slag is 30.2%;

(g) Separating aluminum: and (f) evaporating and concentrating the sodium aluminate solution obtained in the step (f) to 680g/L, cooling to 80 ℃ for sodium aluminate crystallization, and performing liquid-solid separation to obtain sodium aluminate crystals and crystallization mother liquor, wherein the purity of the obtained sodium aluminate is 82.9%.

Example 5

This example differs from example 1 only in that in the secondary dissolution in step (e), the sodium hydroxide solution mass concentration is 50%, and other parameters and conditions are exactly the same as those in example 1.

In the second-stage leaching of this example, the leaching rate of cobalt was 52.2%, the leaching rate of aluminum was 85.4%, the nickel content in the nickel-rich slag was 11.9%, and the cobalt content in the cobalt-rich slag was 26.2%.

Example 6

This example differs from example 1 only in that in the secondary dissolution in step (e), the sodium hydroxide concentration by mass is 45% and the other parameters and conditions are exactly the same as those in example 1.

In the second-stage leaching of this example, the leaching rate of cobalt is 38.4%, the leaching rate of aluminum is 70.2%, the nickel-rich slag contains 9.8% of nickel, and the cobalt-rich slag contains 20.4% of cobalt.

Example 7

This example differs from example 1 only in that in the secondary dissolution in step (e), the sodium hydroxide concentration by mass is 75%, and the other parameters and conditions are exactly the same as those in example 1.

In the second-stage leaching of this example, the leaching rate of cobalt is 56.2%, the leaching rate of aluminum is 85.4%, the nickel content of the nickel-rich slag is 11.6%, and the cobalt content of the cobalt-rich slag is 24.2%.

Example 8

This example differs from example 1 only in that in the secondary digestion in step (e), the digestion temperature is 200 ℃ and other parameters and conditions are exactly the same as in example 1.

In the second-stage leaching of this example, the leaching rate of cobalt was 51.8%, the leaching rate of aluminum was 83.1%, the nickel-rich slag contained 12.3% of nickel, and the cobalt-rich slag contained 23.7% of cobalt.

Example 9

This comparative example differs from example 1 only in that in the step (e) secondary dissolution, the dissolution temperature is 280 ℃ and other parameters and conditions are exactly the same as those in example 1.

The dissolution rate of cobalt obtained in the secondary dissolution of the comparative example is 59.6%, the dissolution rate of aluminum is 89.2%, nickel content of nickel-rich slag is 15.0%, and cobalt content of cobalt-rich slag is 28.0%.

Comparative example 1

This comparative example differs from example 1 only in that in the secondary dissolution of step (e), the dissolution temperature is 180 ℃ and other parameters and conditions are exactly the same as in example 1.

The leaching rate of cobalt obtained in the second-stage leaching of the comparative example is 45.2%, the leaching rate of aluminum is 75.3%, nickel content of nickel-rich slag is 10.2%, and cobalt content of cobalt-rich slag is 22.4%.

Comparative example 2

This comparative example differs from example 1 only in that in the first stage dissolution of step (a), the reaction temperature is 40 ℃ and other parameters and conditions are exactly the same as those in example 1.

The dissolution rate of vanadium obtained in the first-stage dissolution of the comparative example is 67.3%, the dissolution rate of molybdenum is 69.4%, the dissolution rate of cobalt is 60%, the dissolution rate of aluminum is 89.3%, nickel content in nickel-rich slag is 13.8%, and cobalt content in cobalt-rich slag is 24.6%.

And (3) performance testing:

the metal yields separated and recovered by the two-stage extraction resource utilization method for the vanadium-containing waste petroleum catalyst in the above examples and comparative examples are shown in table 2:

TABLE 2

From the above table, the two-stage dissolution method of the invention realizes the resource recovery of vanadium, molybdenum, cobalt, aluminum and nickel, and has high dissolution rate; the defect that the vanadium extraction tailings of the multi-component vanadium-containing waste petroleum catalyst cannot be comprehensively utilized is overcome; the leaching rate of vanadium is 90-97%, that of molybdenum is 95-98%, that of cobalt is 50-60%, and that of aluminum is 85-90%. The grade of cobalt in the cobalt-rich slag can reach 30 percent, and the grade of nickel in the nickel-rich slag can reach more than 15 percent, so that the resource utilization of the waste petroleum catalyst is realized; the two-stage dissolution process realizes the recycling of the dissolution medium; the crystallization mother liquor of sodium vanadate and sodium molybdate can be used for primary dissolution, and the crystallization mother liquor of sodium aluminate can be used for secondary dissolution, so that the process cost is reduced.

And as can be seen from comparison of examples 6-7 with examples 1 and 5, the mass concentration of the sodium hydroxide for secondary dissolution is preferably 50% -70%; the secondary dissolution process keeps the alkali mass concentration, so that higher dissolution rate is obtained, when the alkali mass concentration is higher than 70%, the solution viscosity is higher, the requirement on equipment materials is too high, and meanwhile, the equipment is lost due to too high alkali mass concentration, so that large-scale industrial application is difficult to realize.

Comparing examples 1, 8 and 9 with comparative example 1, it can be seen that the dissolution temperature of the secondary dissolution of the present invention is 200-260 ℃, the dissolution effect is significantly reduced when the dissolution temperature is too low, and a good dissolution rate can be obtained at a higher reaction temperature, but the requirements of solution equipment materials are high, and the selection of suitable equipment is difficult.

It can be seen from comparison of example 1 and comparative example 2 that the first order dissolution temperature is lower than 50 deg.c, the dissolution effect is poor.

The applicant declares that the above description is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are within the scope and disclosure of the present invention.

Claims (26)

1. A resource utilization method for two-stage extraction of vanadium-containing waste petroleum catalyst is characterized by comprising the following steps:

(1) First-stage dissolution: mixing the deoiled vanadium-containing waste petroleum catalyst with a first alkali liquor, and carrying out a dissolution reaction to obtain an alkali solution containing vanadate and molybdate and residues; the first alkali liquor in the step (1) is a sodium hydroxide solution; the deoiling method in the step (1) comprises the steps of carrying out combustion treatment on the vanadium-containing waste petroleum catalyst; the temperature of the combustion treatment is 500-600 ℃;

the resource utilization method also comprises the step of cooling and crystallizing the alkali solution containing vanadate and molybdate obtained in the step (1) to obtain mixed crystals of vanadate and molybdate; the temperature of the cooling crystallization is reduced to 25-45 ℃; the resource utilization method also comprises the steps of dissolving the mixed crystal of vanadate and molybdate to obtain a vanadium-containing solution, adjusting the pH value, and adding ammonium salt to obtain ammonium metavanadate and a vanadium precipitation mother solution;

the V content in the vanadium-containing waste petroleum catalyst is 7.64wt%;

(2) Secondary dissolution: mixing the residue obtained in the step (1) with a second alkali liquor, and carrying out dissolution reaction at a temperature of more than or equal to 200 ℃ to obtain an alkali liquor containing cobaltate and aluminate and nickel-rich slag;

the mass concentration of the first alkali liquor used in the dissolution reaction in the step (1) is 10-40%, the primary dissolution pressure is normal pressure, the mass concentration of the second alkali liquor in the step (2) is 50-70%, and the secondary dissolution pressure is 0.3-0.9 Mpa;

the dissolution rate of vanadium in the first-stage dissolution is 90-97%, and the dissolution rate of molybdenum is 95-98%; the leaching rate of cobalt in the secondary leaching is 50-60%, the leaching rate of aluminum is 85-90%, and the grade of nickel in the nickel-rich slag can reach more than 15%.

2. The resource utilization method according to claim 1, wherein the temperature of the dissolution reaction in the step (1) is 60 to 100 ℃.

3. The resource utilization method according to claim 1, wherein the time for the dissolution reaction in the step (1) is 30 to 120min.

4. A resource utilization method according to claim 1, wherein a ratio of the mass of the alkali in the second alkaline solution to the mass of the residue in the step (2) is 1.5 to 3.

5. A resource utilization method according to claim 1, wherein in the step (2), the second alkali solution is sodium hydroxide solution.

6. The resource utilization method according to claim 1, wherein the time for the dissolution reaction in the step (2) is 1 to 6 hours.

7. A resource utilization method as claimed in claim 1, wherein the temperature of the secondary dissolution in the step (2) is 200 to 260 ℃.

8. A resource utilization method as claimed in claim 1, wherein the step (2) further includes washing the residue with water before mixing the residue with the second alkaline solution.

9. A resource utilization method as claimed in claim 1, wherein the step (2) further comprises washing the nickel-rich slag with water.

10. A resource utilization method as claimed in claim 9, wherein the water washing includes a primary water washing and a secondary water washing.

11. A resource utilization method as claimed in claim 10, wherein the detergent for the primary water washing and/or the secondary water washing is water.

12. The resource utilization method according to claim 10, wherein a washing liquid obtained by the secondary washing is used as a detergent for the primary washing.

13. The method for resource utilization according to claim 1, wherein the pH is adjusted to 7.9 to 8.1.

14. The resource utilization method according to claim 1, wherein the method for adjusting the pH includes adding sulfuric acid.

15. A resource utilization method according to claim 1, wherein the ammonium salt includes ammonium sulfate and/or ammonium chloride.

16. A resource utilization method as claimed in claim 1, further comprising the steps of subjecting the vanadium precipitation mother liquor to ion exchange adsorption, and resolving with sodium hydroxide to obtain a resolving solution.

17. A resource utilization method according to claim 16, wherein the desorption solution is used for adjusting the pH of the vanadium-containing solution.

18. The resource utilization method according to claim 16, further comprising the steps of extracting the vanadium precipitation mother liquor or the vanadium precipitation mother liquor subjected to ion exchange adsorption with N263, and adjusting the pH value to obtain molybdic acid precipitate.

19. The resource utilization method according to claim 1, further comprising standing and aging the alkali solution containing cobaltate and aluminate or adding an oxidant to obtain an aluminate-containing alkali solution and cobalt-rich slag.

20. The resource utilization method of claim 1, wherein the mass concentration of the alkali solution containing cobaltate and aluminate is less than 300g/L, and the alkali solution containing cobaltate and cobalt-rich slag are obtained by adopting a standing aging method.

21. The resource utilization method according to claim 1, wherein the mass concentration of the alkali solution containing cobaltate and aluminate is more than or equal to 300g/L, and an oxidant is added to obtain the alkali solution containing the cobaltate and the cobalt-rich slag.

22. A resource utilization method as claimed in claim 21, wherein the oxidizing agent includes hydrogen peroxide and/or sodium peroxide.

23. The resource utilization method according to claim 19, further comprising the steps of concentrating the aluminate-containing alkali solution, cooling and crystallizing to obtain aluminate crystals and a crystallization mother liquor.

24. A resource utilization method as claimed in claim 23, wherein the concentration is terminated until the mass concentration of the alkali solution in the solution is 650-900 g/L.

25. A resource utilization method according to claim 23, further comprising mixing the crystallization mother liquor with a second alkali liquor for the dissolution reaction in the step (2).

26. The resource utilization method according to claim 1, comprising the steps of:

(a) Deoiling: burning the vanadium-containing waste petroleum catalyst at 500-600 ℃;

(b) First-stage dissolution: mixing the deoiled vanadium-containing waste petroleum catalyst in the step (a) with a sodium hydroxide solution, and carrying out a dissolution reaction for 30-120 min under the conditions that the pressure is normal pressure, the temperature is 60-100 ℃, and the mass concentration of alkali liquor is 10-40% to obtain alkali solution and residue containing sodium vanadate and sodium molybdate;

(c) Vanadium molybdenum crystallization: cooling the alkali solution containing sodium vanadate and sodium molybdate in the step (b) to 25-45 ℃ for crystallization to obtain mixed crystals of sodium vanadate and sodium molybdate;

(d) And (3) separating vanadium: dissolving the mixed crystal of sodium vanadate and sodium molybdate in the step (c) to obtain a vanadium-containing solution, adjusting the pH to 7.9-8.1, adding ammonium sulfate and/or ammonium chloride, precipitating to generate ammonium metavanadate and vanadium precipitation mother liquor, carrying out ion exchange adsorption on the vanadium precipitation mother liquor, and analyzing sodium hydroxide to obtain an analysis solution for adjusting the pH of the vanadium-containing solution;

(e) Separating molybdenum: extracting the vanadium precipitation mother liquor subjected to ion exchange adsorption, and adjusting the pH value to obtain molybdic acid precipitate;

(f) Secondary dissolution: mixing the residue obtained in the step (b) with a sodium hydroxide solution with the mass concentration of 50-70%, wherein the mass ratio of the sodium hydroxide to the residue is 1.5-3, and carrying out a dissolution reaction under the conditions that the pressure is 0.3-1 MPa and the temperature is more than or equal to 200 ℃ to obtain an alkali liquor containing cobaltate and aluminate and a nickel-rich residue;

(g) Separating cobalt: standing and aging the alkali liquor containing sodium cobaltate and sodium aluminate or adding an oxidant to obtain an alkali solution containing sodium aluminate and cobalt-rich slag;

(h) Separating aluminum: concentrating, cooling and crystallizing an alkali solution containing sodium aluminate to obtain sodium aluminate crystals and a crystallization mother liquor; the crystallization mother liquor is returned to the step (f) for secondary dissolution.

Images