CN113293293A

CN113293293A - Method for recovering nickel and cobalt from laterite-nickel ore by resin adsorption method

Info

Publication number: CN113293293A
Application number: CN202110580846.7A
Authority: CN
Inventors: 林洁媛; 孙宁磊; 刘诚; 曹敏; 刘苏宁; 李勇; 丁剑; 彭建华
Original assignee: China ENFI Engineering Corp
Current assignee: China ENFI Engineering Corp
Priority date: 2021-05-26
Filing date: 2021-05-26
Publication date: 2021-08-24
Anticipated expiration: 2041-05-26
Also published as: CN113293293B

Abstract

The invention provides a method for recovering nickel and cobalt from laterite-nickel ore by a resin adsorption method. The method comprises the following steps: step S1, carrying out acid leaching, preneutralization and iron and aluminum removal neutralization on the laterite-nickel ore in sequence to obtain neutralized ore pulp; step S2, adjusting the solid content of the neutralized ore pulp to obtain the pretreated ore pulp with the solid content of below 30%; step S3, performing resin adsorption treatment and screening separation on the pretreated ore pulp by using resin to obtain adsorbed resin and lean ore pulp, wherein the adsorbed resin contains nickel-cobalt ions and impurity metal ions; step S4, washing impurity metal ions in the adsorbed resin by using a washing liquid to obtain washed resin; and step S5, desorbing the nickel and cobalt ions in the washed resin by using a desorption solution to obtain a nickel and cobalt mixed solution and the desorbed resin. The treatment method does not need to load an impurity removal extraction system after desorption, thereby saving the equipment investment and the effect of an extracting agent and reducing the recovery cost of nickel and cobalt.

Description

Method for recovering nickel and cobalt from laterite-nickel ore by resin adsorption method

Technical Field

The invention relates to the technical field of laterite-nickel ore processing, in particular to a method for recovering nickel and cobalt from laterite-nickel ore by a resin adsorption method.

Background

For laterite-nickel ore with relatively low nickel content, a pressure acid leaching wet smelting process is mainly adopted at present. In addition to nickel and cobalt, iron, aluminum, magnesium, manganese, zinc and other impurity metals enter the leaching solution in a large amount in the process of pressure acid leaching. In the current industrial project, a step-by-step chemical precipitation method is mostly adopted for pre-impurity removal and nickel and cobalt pre-enrichment, then an extraction method is used for deeply removing impurities to obtain a nickel solution and a cobalt solution, and finally nickel and cobalt products are prepared. However, the stepwise chemical precipitation method requires repeated solid-liquid separation, and particularly, after the step of removing iron and aluminum by neutralization, iron precipitates easily form a colloid, which makes solid-liquid separation difficult. And the problem that part of nickel and cobalt is lost along with the loss of a liquid phase is difficult to avoid by the conventional solid-liquid separation solution.

The resin adsorption technology is always considered as a metallurgical technology with a great application prospect because of the advantages of high selectivity, relative easiness in separating resin from a liquid phase and the like. The technology originates from smelting of uranium molybdenum ore, a leaching agent and ion exchange resin are added together to be mixed with calcine, the mixture is leached while being absorbed, then the resin is screened out and is desorbed for subsequent treatment, and the like.

US6350420B1 discloses a process for the recovery of nickel and cobalt from a nickel oxide containing ore leach slurry using ion exchange resins. The nickel-containing ore is leached with mineral acid to dissolve the metal. The obtained leached ore pulp is contacted with pyridyl ion exchange resin after the steps of pre-neutralization, neutralization for removing iron and aluminum, copper removal, reduction for hexavalent chromium and the like, and the ion exchange resin selectively loads nickel and cobalt from the ore pulp. The resin was separated by sieving and then desorbed with an acidic solution. After desorption, the resin is returned to the adsorption unit for recycling. The nickel and cobalt in the desorption solution can be separated by a known method such as extraction.

Chinese patent CN101974685B provides a process for extracting nickel and cobalt from laterite ore by using resin-in-pulp adsorption technology. Directly mixing ore pulp subjected to pressure leaching and neutralization iron removal with a sodium type strong-acid cation exchange resin, putting the mixture into a leaching tank, adsorbing nickel and cobalt by the resin, washing the sieved resin with water to obtain slurry, desorbing the slurry with 2-15% sulfuric acid or hydrochloric acid, and extracting and deeply removing impurities from a desorption solution to prepare nickel and cobalt products.

Therefore, in the prior art, the neutralized ore pulp is generally mixed with resin for adsorption, then the mixture is sieved, the obtained loaded resin is directly desorbed by inorganic acid with the concentration of more than 2 percent, and the desorbed resin is returned to the adsorption process for use. The solid content of the pulp is usually high after leaching and neutralization by adding a neutralizing agent, so the rate of target metal ions transferring from the pulp liquid phase to the resin phase is usually slow when the resin is mixed with the pulp. Secondly, even though each commercial functional ion exchange resin has high selectivity to nickel and cobalt, it is difficult to ensure that impurity ions are not co-adsorbed during the adsorption process. In fact, the liquid phase of the neutralized ore pulp of the laterite-nickel ore has high manganese, magnesium and other ions, and has certain affinity with most of nickel-extracting resins at present, so that co-adsorption can occur in the nickel-cobalt adsorption process to a great extent. Therefore, the loaded resin is directly desorbed by acid, and the desorption liquid generally contains impurity metals with certain concentration except nickel and cobalt, mainly magnesium and manganese, and the nickel and cobalt mixed solution can be obtained through a larger extraction and impurity removal system in the subsequent process.

Disclosure of Invention

The invention mainly aims to provide a method for recovering nickel and cobalt from laterite-nickel ore by a resin adsorption method, so as to solve the problem that a complex extraction and impurity removal system is required after adsorption when nickel and cobalt in laterite-nickel ore are recovered by the resin adsorption method in the prior art.

In order to achieve the above objects, according to one aspect of the present invention, there is provided a method for recovering nickel cobalt from a lateritic nickel ore by a resin adsorption method, the method including: step S1, carrying out acid leaching, preneutralization and iron and aluminum removal neutralization on the laterite-nickel ore in sequence to obtain neutralized ore pulp; step S2, adjusting the solid content of the neutralized ore pulp to obtain the pretreated ore pulp with the solid content of below 30%; step S3, performing resin adsorption treatment and screening separation on the pretreated ore pulp by using resin to obtain adsorbed resin and lean ore pulp, wherein the adsorbed resin contains nickel-cobalt ions and impurity metal ions; step S4, washing impurity metal ions in the adsorbed resin by using a washing liquid to obtain washed resin; step S5, desorbing nickel and cobalt ions in the washed resin by using a desorption solution to obtain a nickel and cobalt mixed solution and a desorbed resin; and optionally, returning the desorbed resin to the step S3 for recycling in a step S6.

Further, the resin is IDA resin, and the impurity metal ions include Mn²⁺、Ca²⁺、Mg²⁺And Zn²⁺。

Further, the washing liquid is an acid solution with the pH value of 2-3.5, and the acid solution is selected from one or more of sulfuric acid, hydrochloric acid and nitric acid.

Further, the washing liquid is a cobalt solution with the pH value not less than 3, the cobalt solution is selected from any one or more of cobalt sulfate, cobalt chloride and cobalt nitrate, and the concentration of the cobalt solution is preferably 0.1-10 g/L.

Further, the ratio of the washing liquid to the adsorbed resin is 2: 1-20: 1.

Further, the desorption liquid is n_H ⁺0.01-3.1 mol/L acid solution, wherein the acid solution is one or more selected from sulfuric acid, hydrochloric acid and nitric acid.

Further, the ratio of the desorption solution to the washed resin is 2: 1-20: 1.

Further, the step S2 includes: and (3) adjusting the solid content of the neutralized ore pulp by adopting dilution or partial solid-liquid separation treatment to obtain the pretreated ore pulp with the solid content of below 30%.

Further, the step S4, the step S5 and the step S6 are each independently performed by stirring, cocurrent flow, cross-current flow or countercurrent flow.

Further, the step S1 includes: and (3) carrying out acid leaching, pre-neutralization, hexavalent chromium reduction and iron and aluminum neutralization on the laterite-nickel ore in sequence to obtain neutralized ore pulp.

By applying the technical scheme of the invention, the neutralized ore pulp of the laterite-nickel ore is treated to a proper adsorption condition, and Ni, Co, Mn, Mg and the like in the ore pulp are adsorbed to the resin from the ore pulp by utilizing the affinity of metal ions and functional groups on the resin. Then the resin is washed by a washing liquid to remove Mn on the resin²⁺Mg²⁺Impurity ions. And desorbing the washed resin to obtain the nickel-cobalt solution with ultralow impurity content. The desorbed resin can be returned to the resin adsorption step for reuse. The method utilizes the washing liquid to wash the resin after adsorption, so that impurities can be effectively removed, and the obtained desorption liquid is the nickel-cobalt solution which can be directly subjected to a nickel-cobalt separation process without extraction and impurity removal. In conclusion, the treatment method does not need to load an impurity removal extraction system after desorption, so that the equipment investment and the effect of an extracting agent are saved, and the nickel and cobalt recovery cost is reduced.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

As described in the background of the present application, in the prior art process for extracting nickel and cobalt by using a resin adsorption method, the desorption solution obtained by the process still needs to be subjected to a large-scale extraction and impurity removal system, which is tedious in process and high in cost.

In an exemplary embodiment of the present application, there is provided a method of recovering nickel cobalt from lateritic nickel ore by a resin adsorption method, the method comprising: step S1, carrying out acid leaching, preneutralization and iron and aluminum removal neutralization on the laterite-nickel ore in sequence to obtain neutralized ore pulp; step S2, adjusting the solid content of the neutralized ore pulp to obtain pretreated ore pulp with the solid content of below 30%; step S3, performing resin adsorption treatment on the pretreated ore pulp by using resin, and then screening and separating to obtain adsorbed resin and lean ore pulp, wherein the adsorbed resin contains nickel-cobalt ions and impurity metal ions; step S4, washing impurity metal ions in the adsorbed resin by using a washing liquid to obtain washed resin; step S5, desorbing nickel and cobalt ions in the washed resin by using a desorption solution to obtain a nickel and cobalt mixed solution and a desorbed resin; and optionally, returning the desorbed resin to the step S3 for recycling in a step S6.

According to the treatment method, neutralized ore pulp of the laterite-nickel ore is obtained by adopting a conventional mode in the field, then the ore pulp is treated to a proper adsorption condition, and Ni, Co, Mn, Mg and the like in the ore pulp are adsorbed to resin from the ore pulp by utilizing the affinity of metal ions and functional groups on the resin. Then the resin is washed by a washing liquid to remove Mn on the resin²⁺Mg²⁺Impurity ions. And desorbing the washed resin to obtain the nickel-cobalt solution with ultralow impurity content. The desorbed resin can be returned to the resin adsorption step for reuse. The method utilizes the washing liquid to wash the resin after adsorption, so that impurities can be effectively removed, and the obtained desorption liquid is the nickel-cobalt solution which can be directly subjected to a nickel-cobalt separation process without extraction and impurity removal. In conclusion, the treatment method does not need to load an impurity removal extraction system after desorption, so that the equipment investment and the effect of an extracting agent are saved, and the nickel and cobalt recovery cost is reduced.

The operations of step S1 can be referred to in the prior art, and are not described herein. Due to H⁺The affinity with the functional groups of the resin is strong, so that a large number of functional groups and H are prevented in the adsorption process of the resin⁺And (3) combining to reduce the utilization rate of the resin in unit volume, and preferably selecting the pH value of the neutralized ore pulp to be 3.7-4.3.

In order to ensure that functional groups on the resin can be combined with various metal ions in the laterite-nickel ore pulp, particularly Ni²⁺And Co²⁺Has strong affinity, so that metal ions can be replaced from the ore pulp as much as possible to improve the replacement efficiency of the resin per unit volume, the resin is preferably IDA resin, and the impurity metal ions comprise Mn²⁺、Ca²⁺And Mg²⁺. As the IDA resin, Langshan 207IDA resin, Rohm Hass IRC748 IDA resin, blantt S930, etc. can be used.

The chemical reaction that occurs during resin washing is a displacement reaction of cations in the wash liquor with cations on the resin phase. The order of affinity of the resin functional groups for each cation is: h⁺＞Ni²⁺＞Co²⁺＞Mn²⁺＞＞Ca²⁺＞Mg²⁺From the order of affinity, it can be seen that the acidic solution can remove the impurity metal ions that are poorly bound to the resin. But due to H⁺Has higher affinity with resin functional groups than Ni²⁺And Co²⁺Therefore, part of Ni will be also generated during the washing process²⁺And Co²⁺Washed away, resulting in loss of Ni and Co. Therefore, the washing liquid is preferably an acid solution with the pH value of 2-3.5, and the acid solution is selected from one or more of sulfuric acid, hydrochloric acid and nitric acid. By controlling the pH of the acid solution, i.e. H⁺The concentration is ensured to remove impurity metals and simultaneously reduce the loss of Ni and Co as much as possible.

As mentioned above, the chemical reaction occurring during the resin washing process is a displacement reaction of cations in the washing liquid with cations on the resin phase, and the mechanism of the displacement reaction is based on the order of affinity of the resin functional groups for each cation, i.e.: h⁺＞Ni²⁺＞Co²⁺＞Mn²⁺＞＞Ca²⁺＞Mg²⁺. Thus, in addition to the weak acid scrubbing solution mentioned above, Co may be used²⁺The washing liquid is used for washing the adsorbed resin, and Co is weaker than nickel in affinity with functional groups of the resin, but stronger than manganese, calcium, magnesium and the like, so that impurity metals such as manganese and the like are easily replaced by the cobalt, but nickel is not easily replaced, and the loss rate of the nickel in the washing process is reduced while the impurity metals are removed. In addition, the Co solution can also improve the utilization rate of the resin per unit volume compared with the weak acid washing solution, because the impurity metal such as manganese is replaced by hydrogen when washing is carried out by the weak acid, the functional group of the resin is not utilized when the resin is desorbed by the strong acid subsequently, and the cobalt solution is used as the washing solution to remove the impurities such as manganese from the resinWhen the cobalt is replaced, the cobalt which is one of the target metals is further adsorbed to the resin, and the cobalt on the part of functional groups can enter into desorption liquid during subsequent desorption, so that the utilization rate of the resin in unit volume is improved.

Due to H⁺Has higher affinity with the resin functional group, so H in Co solution should be controlled⁺The washing solution is preferably a cobalt solution with pH not less than 3, and the cobalt solution is selected from any one or more of cobalt sulfate, cobalt chloride and cobalt nitrate. The cobalt solution preferably has a concentration of 0.1 to 10g/L, for example, 0.5g/L, 1.0g/L, 4g/L, 7g/L, etc., and if the concentration is too low, cobalt in the liquid phase is not easily adsorbed to the resin and the impurity metal is replaced, and if the concentration is too high, cobalt loss may be too high.

In a preferred embodiment, the ratio of the washing liquid to the resin after adsorption is 2:1 to 20:1, and may be, for example, 5:1, 8:1, 12:1, 15:1, 18:1, or the like. The quantity of washing liquid is too little, can lead to the impurity metal can't get rid of totally, and the quantity of washing liquid is too many, is the acid solution when the washing liquid probably causes the loss of Ni and Co to can waste reagent, consequently further inject the purification effect and the efficiency of promotion technology are made to the proportion of washing liquid and absorption back resin.

Due to H⁺The affinity with the functional group of the resin is stronger than that of Ni²⁺And Co²⁺Thus, it is preferred that the stripping liquid is n_H ⁺The acid solution may be, for example, 0.05mol/L, 0.1mol/L, 0.5mol/L, 1mol/L, 2mol/L, or the like, in an amount of 0.01 to 3.1 mol/L. Having the above-mentioned H⁺The acid solution with the concentration can desorb Ni and Co on the resin to obtain a nickel-cobalt solution with higher purity; the acid solution is selected from one or more of sulfuric acid, hydrochloric acid and nitric acid.

In one embodiment, the ratio of the desorption solution to the washed resin is preferably 2:1 to 20:1, and may be, for example, 5:1, 8:1, 12:1, 15:1, 18:1, or the like. By controlling the proportion of the desorption solution to the washed resin, the cost can be reduced, and the Ni and Co on the resin can be ensured to be desorbed into the solution. In another embodiment of the present application, in order to achieve the effect of reducing the solid content better, step S2 preferably includes: and (3) adjusting the solid content of the neutralized ore pulp by adopting dilution or partial solid-liquid separation treatment to obtain the pretreated ore pulp with the solid content of below 30%.

The solid content of the neutralized ore pulp is reduced by diluting or partially separating solid and liquid, so that the activity of metal ions in the neutralized ore pulp can be improved, the transfer rate of target metal ions from a liquid phase to resin is accelerated, and the resin adsorption efficiency is improved. The dilution is carried out by taking water as a diluent, and partial solid-liquid separation is carried out by separating out solids with the particle size of more than 180 mu m by adopting a conventional method.

The contacting manner of the materials in the steps S3, S4 and S5 is direct contact, and the contacting can be in a column type or trough type device, and in order to improve the reaction speed and efficiency of each step in the process, preferably, the steps S3, S4 and S5 are independently completed by stirring, cocurrent flow, cross current flow or countercurrent flow.

Part of the laterite-nickel ores have high hexavalent chromium content, so that pretreatment needs to be performed on the laterite-nickel ores, and the step S1 includes: and (3) carrying out acid leaching, pre-neutralization, hexavalent chromium reduction and iron and aluminum neutralization on the laterite-nickel ore in sequence to obtain neutralized ore pulp.

The lean ore pulp obtained in the process can be sent to a tailing treatment system, and the nickel-cobalt mixed solution can be separated from the nickel and the cobalt by a method known in the industry and used for preparing nickel and cobalt products.

The following examples are provided to further illustrate the benefits of the present application.

Example 1

1. The method comprises the steps of sequentially carrying out normal-pressure acid leaching treatment on the laterite-nickel ore, pre-neutralizing, reducing hexavalent chromium, neutralizing, removing iron and aluminum and the like to obtain neutralized ore pulp with the pH of 3.8, adding water to adjust the solid content of the neutralized ore pulp to be 15%, and obtaining pretreated ore pulp, wherein the content of each element in the pretreated ore pulp is shown in table 1.

TABLE 1

Ni(mg/L)	Co(mg/L)	Al(mg/L)	Fe(mg/L)	Cr(mg/L)
					2373.7	353.9	93.6	18.6	66.3
Mg(mg/L)	Na(mg/L)	Mn(mg/L)	Zn(mg/L)	Cu(mg/L)
					1174.7	490.3	1223.3	67	4.9

2. The pretreated pulp is contacted with IDA resin (Lansheng 207), and the volume ratio of the pretreated pulp to the IDA resin is 10: 1. After pretreatment, nickel and cobalt in the slurry phase of the ore are adsorbed on the resin, and the adsorption rate of the nickel and cobalt is higher than 99%. The contacting is carried out in a column apparatus in a cross-flow manner.

3. And (4) after adsorption, screening and separating the resin and the ore pulp to obtain the resin after adsorption and the lean ore pulp.

4. And (3) taking 10g/L cobalt sulfate solution with pH of 5 as washing liquid to contact with the resin after adsorption, wherein the volume ratio of the washing liquid to the resin after adsorption is 5: 1. The contacting was carried out in a column apparatus in countercurrent to obtain the washed resin.

5. By n_H ⁺Sulfuric acid of 3.1mol/L is used as desorption liquid to be contacted with the washed resin, and the volume ratio of the desorption liquid to the resin is 20: 1. The contact is completed in a column type device in a countercurrent mode to obtain nickel-cobalt mixed liquor and desorbed resin, wherein the contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed liquor are all lower than 0.5mg/L, and the nickel-cobalt desorption rate is higher than 99%.

6. The desorbed resin is regenerated and returned to the adsorption process for reuse.

Example 2

1. The method comprises the following steps of sequentially carrying out pressure acid leaching treatment on the laterite-nickel ore, carrying out procedures of pre-neutralization, hexavalent chromium reduction, neutralization iron and aluminum removal and the like to obtain neutralized ore pulp with the pH value of 4.0, carrying out partial solid-liquid separation on the neutralized ore pulp, separating solid particles with the particle size of more than or equal to 18 mu m from the ore pulp, wherein the solid content of the separated ore pulp is 25%, so as to obtain pretreated ore pulp, and the content of each element in the pretreated ore pulp is shown in Table 1.

TABLE 2

Ni(mg/L)	Co(mg/L)	Al(mg/L)	Fe(mg/L)	Cr(mg/L)
					8500	920	2600	307.4	1990
Mg(mg/L)	Ca(mg/L)	Mn(mg/L)	Zn(mg/L)	Cu(mg/L)
					9620	40	5080	163	34

2. And (3) contacting the pretreated ore pulp with IDA resin (Lansheng 207), wherein the volume ratio of the pretreated ore pulp to the IDA resin is 5: 1. After pretreatment, nickel and cobalt in the slurry phase of the ore are adsorbed on the resin, and the adsorption rate of the nickel and cobalt is higher than 99%. The contacting is accomplished in a trough-type apparatus in a co-current manner.

4. And (3) taking 1g/L cobalt nitrate solution with pH of 4 as a washing solution to contact the adsorbed resin, wherein the volume ratio of the washing solution to the resin is 3: 1. The contacting is done in a tank type apparatus in a cross-flow fashion to obtain the washed resin.

5. By n_H ⁺Nitric acid of 1.5mol/L is used as desorption liquid to contact with the washed IDA resin, and the volume ratio of the desorption liquid to the resin is 15: 1. The contact is completed in a groove type device in a cross flow mode to obtain a nickel-cobalt mixed solution and desorbed resin, wherein the contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution are all lower than 0.5mg/L, and the nickel-cobalt desorption rate is all higher than 99%.

Example 3

Sequentially carrying out normal-pressure acid leaching treatment, pre-neutralizing, hexavalent chromium reduction, iron and aluminum removal and other processes on the laterite-nickel ore to obtain neutralized ore pulp with the pH value of 4.1, adding water to adjust the solid content of the neutralized ore pulp to be 30% to obtain pretreated ore pulp, wherein the content of each element in the pretreated ore pulp is shown in table 1.

TABLE 3

Ni(mg/L)	Co(mg/L)	Al(mg/L)	Fe(mg/L)	Cr(mg/L)
					4250	460	1300	153.7	995
Mg(mg/L)	Ca(mg/L)	Mn(mg/L)	Zn(mg/L)	Cu(mg/L)
					4810	20	2540	81.5	17

2. And (3) contacting the pretreated ore pulp with IDA resin (Lansheng 207), wherein the volume ratio of the pretreated ore pulp to the IDA resin is 8: 1. after pretreatment, nickel and cobalt in the slurry phase of the ore are adsorbed on the resin, and the adsorption rate of the nickel and cobalt is higher than 99%. The contacting is carried out in a countercurrent manner in a column apparatus.

4. And (3) contacting 0.001g/L cobalt chloride solution with pH of 4.5 as a washing solution with the resin after adsorption, wherein the volume ratio of the washing solution to the resin after adsorption is 20: 1. The contacting was carried out in a column apparatus in countercurrent to obtain the washed resin.

5. By n_H ⁺Hydrochloric acid of 2mol/L is used as desorption liquid to be contacted with the washed IDA resin, and the volume ratio of the desorption liquid to the resin is 10: 1. The contact is completed in a column type device in a parallel flow mode to obtain a nickel-cobalt mixed solution and desorbed resin, wherein the contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution are all lower than 0.5mg/L, and the nickel-cobalt desorption rate is all higher than 99%.

Example 4

1. The method comprises the steps of sequentially carrying out normal-pressure acid leaching treatment on laterite-nickel ore, pre-neutralizing, hexavalent chromium reduction, neutralizing, iron and aluminum removal and the like to obtain neutralized ore pulp, adjusting the pH value of the end point of the ore pulp to be 4.0, carrying out partial solid-liquid separation on the neutralized ore pulp, separating solid particles larger than or equal to 18 mu m in the ore pulp, wherein the solid content of the separated ore pulp is 25%, so that the pretreated ore pulp is obtained, and the content of each element in the pretreated ore pulp is shown in table 1.

TABLE 4

2. And (3) contacting the pretreated ore pulp with IDA resin (Lansheng 207), wherein the volume ratio of the pretreated ore pulp to the IDA resin is 4: 1. after pretreatment, nickel and cobalt in the slurry phase of the ore are adsorbed on the resin, and the adsorption rate of the nickel and cobalt is higher than 99%. The contacting is accomplished in a trough-type apparatus in a co-current manner.

3. And separating the resin from the ore pulp after adsorption to obtain the resin after adsorption and the lean ore pulp.

4. And (3) contacting the adsorbed resin with a washing solution to wash impurity metals such as manganese, zinc and the like from the resin, and separating to obtain the washed resin. The washing solution is hydrochloric acid with pH 2, and the volume ratio of the washing solution to the resin is 5: 1. The contacting is carried out in a countercurrent manner in a column apparatus.

5. And (3) contacting the washed resin with desorption liquid, desorbing nickel and cobalt from the resin, and separating to obtain nickel and cobalt mixed liquid and the desorbed resin. The stripping liquid is n_H ⁺1mol/L hydrochloric acid, and the volume ratio of the washing liquid to the resin is 20: 1. The contacting is carried out in a countercurrent manner in a column apparatus. The contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution are all lower than 0.5mg/L, and the desorption rate of nickel-cobalt is higher than 99%.

Example 5

1. The method comprises the steps of sequentially carrying out normal-pressure acid leaching treatment on the laterite-nickel ore, pre-neutralizing, reducing hexavalent chromium, neutralizing, removing iron and aluminum and the like to obtain neutralized ore pulp with the pH of 4.1, adding water to adjust the solid content of the neutralized ore pulp to be 30%, and obtaining pretreated ore pulp, wherein the content of each element in the pretreated ore pulp is shown in table 1.

TABLE 5

2. And (3) contacting the diluted ore pulp with IDA resin (Lansheng 207), wherein the volume ratio of the pretreated ore pulp to the IDA resin is 10: 1. nickel and cobalt, magnesium, manganese, zinc and calcium in the slurry phase of the pretreated ore are adsorbed on the resin, the adsorption is balanced within 5 hours, and the adsorption rate of the nickel and cobalt is higher than 99 percent. The contact is accomplished in a tank type apparatus with agitation.

4. And (3) contacting the adsorbed resin with a washing solution to wash impurity metals such as manganese, zinc and the like from the resin, and separating to obtain the washed resin. The washing solution was sulfuric acid with pH 3, and the volume ratio of washing solution to resin was 15: 1. The contacting is carried out in a column apparatus in a cross-flow manner.

5. And (3) contacting the washed resin with desorption liquid, desorbing nickel and cobalt from the resin, and separating to obtain nickel and cobalt mixed liquid and the desorbed resin. The stripping liquid is n_H ⁺2mol/L sulfuric acid, and the volume ratio of the desorption solution to the resin is 3: 1. The contact is completed in a column type device in a parallel flow mode to obtain a nickel-cobalt mixed solution, wherein the contents of manganese, magnesium, calcium and zinc are all lower than 0.5mg/L, and the desorption rate of nickel and cobalt is higher than 99%.

Example 6

The difference from example 1 is that in step 2, the volume ratio of the pretreated pulp to the IDA resin is 2: 1.

After the step 2, the nickel and cobalt adsorption rate is higher than 99%. After the step 5, the contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution are all lower than 0.5mg/L, and the desorption rate of nickel-cobalt is all higher than 99%.

Example 7

The difference from example 1 is that in step 2, the volume ratio of the pretreated pulp to the IDA resin is 20: 1.

Example 8

The difference from example 1 is that in step 4, a 10g/L cobalt sulfate solution having a pH of 2 was contacted with the resin after adsorption as a washing solution, and the volume ratio of the washing solution to the resin after adsorption was 5: 1.

After the step 5, the contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution are all lower than 0.5mg/L, and the desorption rate of nickel-cobalt is all higher than 99%.

Example 9

The difference from example 1 is that in step 4, 10g/L cobalt sulfate solution with pH 5 is used as washing liquid to contact with the resin after adsorption, and the volume ratio of the washing liquid to the resin after adsorption is 1: 1.

After the step 5, the content of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution is 20-50 mg/L, 20-50 mg/L and 20-50 mg/L, and the desorption rate of nickel-cobalt is higher than 99%.

Example 10

The difference from example 1 is that in step 5, n is used_H ⁺Sulfuric acid of 0.001mol/L is used as desorption liquid to be contacted with the washed resin, and the volume ratio of the desorption liquid to the resin is 20: 1.

After the step 5, the contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution are all lower than 0.5mg/L, and the desorption rate of nickel-cobalt is 40-80%.

Example 11

The difference from example 1 is that in step 5, n is used_H ⁺Sulfuric acid of 3.1mol/L is used as desorption liquid to be contacted with the washed resin, and the volume ratio of the desorption liquid to the resin is 2: 1.

After the step 5, the contents of manganese, magnesium, calcium and zinc in the nickel-cobalt mixed solution are all lower than 0.5mg/L, and the desorption rate of nickel-cobalt is 99%.

Example 12

The difference from example 1 is that in step 5, n is used_H ⁺Sulfuric acid of 3.1mol/L is used as desorption liquid to be contacted with the washed resin, and the volume ratio of the desorption liquid to the resin is 1: 1.

Example 13

The difference from example 4 is that in step 4, the pH of the hydrochloric acid washing solution is 3.5, and the volume ratio of the washing solution to the resin is 5: 1.

Example 14

The difference from example 4 is that in step 4, the pH of the hydrochloric acid washing solution is 4.5, and the volume ratio of the washing solution to the resin is 5: 1.

After the step 5, the content of manganese in the nickel-cobalt mixed solution is 20-100 mg/L, the content of magnesium is 20-100 mg/L, the content of calcium is 20-100 mg/L, the content of zinc is 20-100 mg/L, and the desorption rate of nickel-cobalt is higher than 99%.

Example 15

The difference from example 4 is that in step 4, the pH of the hydrochloric acid washing solution is 2, and the volume ratio of the washing solution to the resin is 2: 1.

Example 16

The difference from example 4 is that in step 4, the pH of the hydrochloric acid washing solution is 2, and the volume ratio of the washing solution to the resin is 20: 1.

Example 17

The difference from example 4 is that in step 4, the pH of the hydrochloric acid washing solution is 2, and the volume ratio of the washing solution to the resin is 1: 1.

Example 18

The difference from example 1 is that the concentration of the cobalt sulfate solution in step 4 was 0.01 g/L.

Example 19

The difference from example 1 is that in step 5, n is used_H ⁺And (3) taking 0.01mol/L sulfuric acid as desorption solution to contact with the washed resin, wherein the volume ratio of the desorption solution to the resin is 20: 1.

Comparative example 1

The difference from the example 1 is that after the neutralization by adding water, the solid content of the ore pulp is 40 percent, and the pretreated ore pulp is obtained, wherein the content of each element in the pretreated ore pulp is shown in the table 6. After the step 2, the nickel-cobalt adsorption rate is about 40-80%.

TABLE 6

Ni(mg/L)	Co(mg/L)	Al(mg/L)	Fe(mg/L)	Cr(mg/L)
					7104.8	769.0	2173.2	256.9	1663.4
Mg(mg/L)	Na(mg/L)	Mn(mg/L)	Zn(mg/L)	Cu(mg/L)
					8041.0	33.4	4246.2	136.2	28.4

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

according to the treatment method, neutralized ore pulp of the laterite-nickel ore is obtained by adopting a conventional mode in the field, then the ore pulp is treated to a proper adsorption condition, and Ni, Co, Mn, Mg and the like in the ore pulp are adsorbed to resin from the ore pulp by utilizing the affinity of metal ions and functional groups on the resin. Then the resin is washed by a washing liquid to remove Mn on the resin²⁺Mg²⁺Impurity ions. Desorbing the washed resinAnd treating to obtain the nickel-cobalt solution with ultralow impurity content. The desorbed resin can be returned to the resin adsorption step for reuse. The method utilizes the washing liquid to wash the resin after adsorption, so that impurities can be effectively removed, and the obtained desorption liquid is the nickel-cobalt solution which can be directly subjected to a nickel-cobalt separation process without extraction and impurity removal. In conclusion, the treatment method does not need a loaded extraction system after desorption, thereby saving the equipment investment and the effect of the extractant and reducing the recovery cost of nickel and cobalt.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for recovering nickel and cobalt from laterite-nickel ore by a resin adsorption method, which is characterized by comprising the following steps:

step S1, carrying out acid leaching, preneutralization and iron and aluminum removal neutralization on the laterite-nickel ore in sequence to obtain neutralized ore pulp;

step S2, adjusting the solid content of the neutralized ore pulp to obtain pretreated ore pulp with the solid content of below 30%;

step S3, performing resin adsorption treatment and screening separation on the pretreated ore pulp by using the resin to obtain adsorbed resin and lean ore pulp, wherein the adsorbed resin contains nickel-cobalt ions and impurity metal ions;

step S4, washing impurity metal ions in the adsorbed resin by using a washing liquid to obtain washed resin;

step S5, desorbing nickel and cobalt ions in the washed resin by using a desorption solution to obtain a nickel and cobalt mixed solution and a desorbed resin; and

optionally, in step S6, the desorbed resin is returned to step S3 for recycling.

2. Root of herbaceous plantThe method of claim 1, wherein the resin is an IDA resin and the impurity metal ions comprise Mn²⁺、Ca²⁺、Mg²⁺And Zn²⁺。

3. The method according to claim 1, wherein the washing solution is an acid solution with a pH of 2-3.5, and the acid solution is selected from any one or more of sulfuric acid, hydrochloric acid and nitric acid.

4. The method according to claim 1, wherein the washing solution is a cobalt solution with pH being not less than 3, the cobalt solution is selected from any one or more of cobalt sulfate, cobalt chloride and cobalt nitrate, and the concentration of the cobalt solution is preferably 0.1-10 g/L.

5. The method according to claim 3 or 4, wherein the ratio of the washing liquid to the adsorbed resin is 2:1 to 20: 1.

6. The method of claim 1, wherein the desorption liquid is n_H ⁺0.01-3.1 mol/L acid solution, wherein the acid solution is selected from one or more of sulfuric acid, hydrochloric acid and nitric acid.

7. The method according to claim 6, wherein the ratio of the desorption solution to the washed resin is 2:1 to 20: 1.

8. The method according to any one of claims 1 to 7, wherein the step S2 includes:

and (3) adjusting the solid content of the neutralized ore pulp by adopting dilution or partial solid-liquid separation treatment to obtain the pretreated ore pulp with the solid content of below 30%.

9. The method of claim 1, wherein the step S4, the step S5, and the step S6 are each independently performed by stirring, co-current flow, cross-current flow, or counter-current flow.

10. The method according to claim 1, wherein the step S1 includes:

and (3) carrying out acid leaching, pre-neutralization, hexavalent chromium reduction and iron and aluminum neutralization on the laterite-nickel ore in sequence to obtain neutralized ore pulp.