Method for preparing manganese-containing oxidizing agent from laterite-nickel ore hydrometallurgy barren liquor and application of manganese-containing oxidizing agent

Abstract

The invention discloses a method for preparing a manganese-containing oxidizing agent from laterite-nickel ore hydrometallurgy barren liquor and application of the manganese-containing oxidizing agent, and relates to the technical field of laterite-nickel ore hydrometallurgy. The method for preparing the manganese-containing oxidizing agent from the laterite-nickel ore wet smelting barren liquor comprises the steps that S1, the oxidizing agent and a neutralizing agent are added into the laterite-nickel ore wet smelting barren liquor, an oxidation manganese precipitation reaction is carried out, and manganese precipitation ore pulp is obtained; and S2, carrying out solid-liquid separation on the manganese precipitation ore pulp to obtain the manganese-containing oxidizing agent. The laterite-nickel ore hydrometallurgy barren liquor is treated through the method, the precipitation rate of Mn is high, the content of Mn < 2 + > in discharged waste water is reduced, the content of Mn < 4 + > in the oxidizing agent is high, and the oxidizing property is good.

Description

Technical Field

[0001] The invention relates to the technical field of laterite nickel ore hydrometallurgy, and in particular to a method for preparing a manganese-containing oxidant by using barren liquid from laterite nickel ore hydrometallurgy and application thereof. Background Art

[0002] Laterite nickel ore is an ore containing nickel, iron and other metals, mainly distributed in tropical and subtropical regions. Laterite nickel ore hydrometallurgy is a chemical process for extracting nickel from laterite nickel ore, which generally includes ore dressing pulping, high-pressure acid leaching, pre-neutralization, CCD countercurrent washing, neutralization and iron and aluminum removal, one-stage nickel and cobalt precipitation, two-stage nickel and cobalt precipitation and other processes. After the hydrometallurgy is completed, in addition to nickel precipitate, liquid separation will also be obtained. The liquid separation generally contains manganese ions. If it is not treated, it will pollute the environment on the one hand and cause waste of resources on the other hand. At present, the manganese remaining in the liquid after the second-stage nickel and cobalt precipitation is usually precipitated into the tailings in the tailings neutralization process, resulting in all of it being wasted. Summary of the invention

[0003] The main purpose of the present invention is to provide a method for preparing a manganese-containing oxidant by using lean liquid from laterite nickel ore hydrometallurgy and its application, so as to solve the problem of serious waste of manganese resources in lean liquid from laterite nickel ore hydrometallurgy.

[0004] In order to solve the above technical problems, according to a first aspect of the present invention, a method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore is provided, the method comprising:

[0005] S1, adding an oxidant and a neutralizer to the barren liquid of laterite nickel ore hydrometallurgy to carry out an oxidation and manganese precipitation reaction to obtain a manganese precipitation slurry; the oxidant comprises SO2 and O2;

[0006] S2, performing solid-liquid separation on the manganese precipitated slurry to obtain a manganese-containing oxidant.

[0007] Furthermore, the volume ratio of SO2 and O2 is (1-10):(19-21); the volume ratio of laterite nickel ore hydrometallurgical lean liquid and O2 is 1:(0.1-15).

[0008] Further, the neutralizing agent includes at least one of NaOH, Na2CO3, NaHCO3, KOH, K2CO3, KHCO3, CaO, Ca(OH)2, CaCO3, MgO, Mg(OH)2, and MgCO3.

[0009] Furthermore, the pH value of the oxidation-precipitation manganese reaction is 4.0-9.0.

[0010] Furthermore, the temperature of the oxidation precipitation manganese reaction is 30° C. to 90° C., and the time of the oxidation precipitation manganese reaction is 1 h to 10 h.

[0011] Furthermore, in S2, solid-liquid separation is performed by thickening.

[0012] Furthermore, in S2, after solid-liquid separation, underflow slurry is obtained, and the underflow slurry is filter-filtered to obtain a manganese-containing oxidant.

[0013] Furthermore, in the barren liquor of laterite nickel ore hydrometallurgy, the concentration of Mn is 0.1 g / L to 10 g / L, the concentration of Ni is lower than 1.0 g / L, the concentration of Co is lower than 0.3 g / L, and the concentration of Mg is lower than 15 g / L.

[0014] Furthermore, the barren liquid from the laterite nickel ore hydrometallurgy is one or both of a separation liquid obtained after the first stage of nickel-cobalt precipitation and a separation liquid obtained after the second stage of nickel-cobalt precipitation.

[0015] According to a second aspect of the present invention, there is provided an application of a manganese-containing oxidant prepared by the method of the first aspect of the present invention in a laterite nickel ore hydrometallurgy process, wherein the laterite nickel ore hydrometallurgy process comprises high-pressure acid leaching, pre-neutralization, neutralization to remove iron and aluminum, a first-stage nickel-cobalt precipitation, and a second-stage nickel-cobalt precipitation, and the manganese-containing oxidant is used in the high-pressure acid leaching and / or pre-neutralization step.

[0016] Furthermore, the manganese-containing oxidant is used in the high-pressure acid leaching step. In the high-pressure acid leaching step, the dry mass ratio of the manganese-containing oxidant to the laterite nickel ore is (0.01-5):100.

[0017] Furthermore, the acid-ore ratio is 200kg / t to 500kg / t.

[0018] Furthermore, the reaction temperature is 240°C to 280°C.

[0019] Furthermore, the reaction time is 0.5h to 2h.

[0020] Furthermore, the reaction pressure is 4 MPa to 6 MPa.

[0021] By applying the technical scheme of the present invention, the manganese element in the wet smelting barren liquor of laterite nickel ore can be effectively recovered by oxidizing and precipitating manganese with an oxidant and a neutralizer, and the Mn in the obtained manganese-containing oxidant is 4+ It has a high content and good oxidizability, and is suitable for use in the high-pressure acid leaching and pre-neutralization process of hydrometallurgy. It can effectively reduce the Fe content in the high-pressure acid leaching liquid and the pre-neutralization liquid. 2+ content. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The flowchart of preparing a manganese-containing oxidant by hydrometallurgical smelting of barren liquid from laterite nickel ore in the examples. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0024] As described in the background technology, the existing laterite nickel ore hydrometallurgy process produces waste liquid, which contains high content of non-ferrous metal ions such as manganese ions. If it is directly discharged without treatment, it will pollute the environment on the one hand and waste resources on the other hand. In order to solve the above technical problems, in a typical embodiment of the present invention, a method for preparing a manganese-containing oxidant from a laterite nickel ore hydrometallurgy lean liquid is provided, and the preparation process is as follows: Figure 1 As shown, including:

[0025] S1, adding an oxidant and a neutralizer to the barren liquid of laterite nickel ore hydrometallurgy to carry out an oxidation and manganese precipitation reaction to obtain a manganese precipitation slurry; the oxidant comprises SO2 and O2;

[0026] S2, performing solid-liquid separation on the manganese precipitated slurry to obtain a manganese-containing oxidant.

[0027] Laterite nickel ore is an ore containing nickel, iron, cobalt, silicon, magnesium, manganese and other elements. It is widely used, mainly in the manufacture of stainless steel, alloy steel, nickel-based alloys, nickel-hydrogen batteries, catalysts, magnetic materials, etc. It plays an important role in the fields of aerospace, electronics, chemical industry and energy. The output of laterite nickel ore accounts for the highest proportion of the total output of nickel ore. Its smelting methods include hydrometallurgy and pyrometallurgy. Hydrometallurgy includes high-pressure acid leaching and ammonia leaching, and pyrometallurgy includes direct reduction and electric furnace smelting. In the hydrometallurgy process, high-pressure acid leaching is the most widely used method with relatively low energy consumption.

[0028] The high-pressure acid leaching method generally includes the following steps: ore dressing and pulping, high-pressure acid leaching, pre-neutralization, CCD countercurrent washing, neutralization and iron and aluminum removal, first-stage nickel and cobalt precipitation, and second-stage nickel and cobalt precipitation. Each step is described in detail:

[0029] Ore dressing and pulping: Wash the laterite nickel ore, make pulp and ball mill to achieve the appropriate particle size to improve leaching efficiency;

[0030] High-pressure acid leaching: Mix the laterite nickel ore slurry with sulfuric acid, react under high temperature and high pressure, dissolve metals such as nickel and cobalt into the solution, and obtain a high-pressure acid leaching solution;

[0031] Pre-neutralization: neutralize the high pressure acid leaching solution with a neutralizer such as limestone, and neutralize the residual acid in the high pressure acid leaching solution with a neutralizer;

[0032] CCD countercurrent washing: solid-liquid separation is performed through CCD countercurrent washing to obtain CCD countercurrent washing leachate and leach residue;

[0033] Neutralization and iron and aluminum removal: refers to adding a neutralizer to adjust the pH value of the CCD countercurrent washing leachate to remove Fe and Al as well as impurities such as Si and Cr in the solution. If there is Fe in the solution 2+ , additional oxidants need to be added to oxidize to Fe 3+ Hydrolyze and precipitate, and obtain neutralized iron and aluminum-removed liquid and iron-aluminum slag after solid-liquid separation;

[0034] One-stage nickel-cobalt precipitation: refers to mixing the neutralized iron and aluminum removal solution with an alkaline reagent such as sodium hydroxide, adjusting the pH value to 7.0-7.6 for one-stage nickel-cobalt precipitation. The obtained nickel-cobalt precipitate can be directly processed into nickel-cobalt hydroxide (MHP) products, and the obtained one-stage nickel-cobalt precipitation solution enters the next process;

[0035] The second stage nickel-cobalt precipitation refers to mixing the first stage nickel-cobalt precipitation liquid with lime milk, adjusting the pH value to 7.6-8.2, and performing the second stage nickel-cobalt precipitation. After solid-liquid separation, the nickel-cobalt precipitate and the second stage nickel-cobalt precipitation liquid are obtained. The nickel-cobalt precipitate is returned to the pre-neutralization stage for treatment to improve the recovery rate of Ni and Co.

[0036] After the first stage or second stage nickel-cobalt precipitation is completed, the content of Ni and Co metal ions in the obtained separation liquid will be reduced, which can be called laterite nickel ore hydrometallurgical lean liquid.

[0037] The present invention simultaneously adds an oxidant and a neutralizer to the laterite nickel ore wet smelting barren liquor, so that the divalent manganese ions in the wet smelting barren liquor can be oxidized into high-valent manganese ions, and the recovered product can be further used as an oxidant in the wet smelting process of the laterite nickel ore through further solid-liquid separation, thereby realizing the recycling of resources, and also can reduce the content of non-ferrous metal ions in the laterite nickel ore wet smelting barren liquor, thereby being environmentally friendly.

[0038] In some embodiments, the volume ratio of SO2 and O2 is (1-10):(19-21), specifically 1:19, 1:20, 1:21, 10:19, 10:20, 10:21, or other values ​​within the range, which are not particularly limited herein.

[0039] The volume ratio of SO2 and O2 has a great influence on the oxidation efficiency. Generally, when the two exist at the same time, SO2 acts as a reducing agent and O2 acts as an oxidant. However, for the laterite nickel ore hydrometallurgical lean liquor of the present invention, the oxidation efficiency of O2 can be improved by adding SO2 and controlling the volume ratio of SO2 and O2 within the above range. Compared with single O2, the content of high-valent manganese in the manganese-containing oxidant prepared by the present invention is higher.

[0040] In some embodiments, O2 is derived from at least one of pure oxygen, air, and a mixture of oxygen and an inert gas; SO2 is derived from at least one of pure sulfur dioxide, flue gas containing sulfur dioxide, and a mixture of sulfur dioxide and an inert gas.

[0041] In some embodiments, the volume ratio of the laterite nickel ore hydrometallurgical lean solution to O2 is 1:(0.1-15). By controlling the volume ratio of the laterite nickel ore hydrometallurgical lean solution to the oxidant within the above range, the oxidation effect of the metal ions can be significantly improved, and the low-valent manganese ions can be converted into high-valent manganese ions.

[0042] In some embodiments, the neutralizing agent includes at least one of NaOH, Na2CO3, NaHCO3, KOH, K2CO3, KHCO3, CaO, Ca(OH)2, CaCO3, MgO, Mg(OH)2, MgCO3.

[0043] The above-mentioned neutralizing agent can react with sulfuric acid or nitric acid to generate a soluble salt, which will not significantly affect the composition of the manganese-containing oxidant, that is, it is helpful to obtain a high-purity high-valent manganese oxide material.

[0044] In some embodiments, the pH value of the oxidative manganese precipitation reaction is 4.0-9.0, specifically 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, etc., or other values ​​within the range, and no other limitation is made herein.

[0045] Controlling the pH value of the oxidation precipitation reaction can increase the precipitation rate of Mn and help increase the Mn content in the precipitate. 4+ The proportion of oxide materials can be improved, thereby improving the oxidizability of the obtained oxide materials and expanding their application range.

[0046] In some embodiments, the temperature of the manganese precipitation oxidation reaction is 30°C to 90°C, specifically 30°C, 40°C, 45°C, 60°C, 80°C, 90°C, etc., or other values ​​within the range, which are not specifically limited herein; the manganese precipitation oxidation reaction time is 1h to 10h, specifically 1h, 3h, 5h, 8h, 10h, etc., or other values ​​within the range, which are not specifically limited herein.

[0047] The temperature of the oxidation precipitation reaction is controlled within the above range, and the oxidation efficiency and precipitation rate are high, and the content of high-valent manganese in the obtained precipitate is high. The reaction time of oxidation precipitation is based on the Mn content in the lean solution of laterite nickel ore hydrometallurgy. 2+ For the lean solution of laterite nickel ore hydrometallurgy, controlling the oxidation manganese precipitation reaction time within the above range can make the Mn precipitation rate reach more than 99%, and the recovery rate is higher.

[0048] In some embodiments, in S2, solid-liquid separation is performed by thickening. Thickening can increase the concentration of solid particles and reduce the amount of liquid in subsequent processing. After thickening, the solid particles are easier to dry and filter, which helps to improve the recovery rate. It is generally processed by a thickener or a sedimentation tank.

[0049] In some embodiments, in S2, after solid-liquid separation, underflow slurry is obtained, and the underflow slurry is filter-filtered to obtain a manganese-containing oxidant.

[0050] Filter pressing can further improve the solid-liquid separation efficiency and increase the purity and quality of solid particles in the slurry.

[0051] In some embodiments, in the barren liquor of laterite nickel ore hydrometallurgy, the concentration of Mn is 0.1 g / L to 10 g / L, the concentration of Ni is lower than 1.0 g / L, the concentration of Co is lower than 0.3 g / L, and the concentration of Mg is lower than 15 g / L.

[0052] The above-mentioned laterite nickel ore wet smelting barren liquor is treated to obtain a manganese-containing oxidant with a higher content of high-valent manganese, which is more suitable for recycling as an oxidant.

[0053] In another typical embodiment of the present invention, there is provided an application of the manganese-containing oxidant in the above embodiment in a hydrometallurgical process of laterite nickel ore, wherein the hydrometallurgy comprises high-pressure acid leaching, pre-neutralization, neutralization to remove iron and aluminum, a first-stage nickel-cobalt precipitation, and a second-stage nickel-cobalt precipitation step, and the manganese-containing oxidant is used in the high-pressure acid leaching and / or pre-neutralization step.

[0054] The use of the manganese-containing oxidant in the high pressure acid leaching step can directly convert Fe 2+ Oxidized to Fe2O3, compared with the traditional high-pressure acid leaching method, the iron content in the acid leaching solution will be significantly reduced. In addition, compared with the oxidation or precipitation treatment of the acid leaching solution, the oxidation effect is better, Fe 2+ The removal efficiency is high. Traditional oxidation and precipitation to remove Fe 2+ The method is to convert it into iron hydroxide, but iron hydroxide generally exists in the form of colloid, and the particles are small, which is difficult to separate. In the high-pressure acid leaching step, the manganese-containing oxidant in the above embodiment of the present invention is used to directly convert Fe 2+ Converted into Fe2O3 solid, Fe 2+ The removal rate is high and the separation is simple. In addition, the cost of oxidant auxiliary materials can be significantly reduced by extracting oxides from the barren liquor of laterite nickel ore hydrometallurgy and applying them in the hydrometallurgy process.

[0055] When used in the high-pressure acid leaching step, the dry mass ratio of the manganese-containing oxidant to the laterite nickel ore is (0.01-5):100; in the dry basis of the laterite nickel ore, the mass content of Ni is 0.5%-2%, the mass content of Co is 0.05%-0.2%, the mass content of Fe is 20%-50%, the mass content of Al is 1%-10%, the mass content of Mn is 0.5%-1.5%, and the mass content of Mg is 0.1%-10%.

[0056] By controlling the mass ratio of the manganese-containing oxidant and the laterite nickel ore, most of the Fe in the laterite nickel ore can be converted into Fe2O3 solid and separated.

[0057] In some embodiments, the acid-ore ratio in the high-pressure acid leaching step is 200kg / t to 500kg / t, the acid is sulfuric acid or nitric acid, and the mass concentration of sulfuric acid or nitric acid is 96%-99%; the ore is a dry basis of laterite nickel ore, and the laterite nickel ore is generally made into a slurry with a solid mass concentration of about 40% and then subjected to high-pressure acid leaching.

[0058] The acid-ore ratio is controlled in order to extract as much metal as possible from laterite nickel ore into the solution for subsequent separation and recovery.

[0059] In some embodiments, the reaction temperature in the high-pressure acid leaching step is 240° C. to 280° C., the reaction time is 0.5 h to 2 h, and the reaction pressure is 4 MPa to 6 MPa.

[0060] The high pressure acid leaching conditions are controlled to increase the Fe 2+ The efficiency of conversion into Fe2O3 solid is improved, thereby improving the removal rate of Fe.

[0061] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0062] The laterite nickel ore hydrometallurgical barren liquid used in the embodiments and comparative examples is the separated liquid obtained after solid-liquid separation of the first-stage nickel-cobalt precipitation or the second-stage nickel-cobalt precipitation, and its composition is as follows:

[0063] Lean solution A: Mn: 2.3 g / L, Ni: 0.01 g / L, Co: 0.01 g / L, Mg: 6.5 g / L.

[0064] Lean solution B: Mn: 2.8 g / L, Ni: 0.5 g / L, Co: 0.3 g / L, Mg: 7.1 g / L.

[0065] Laterite nickel ore: The selected laterite nickel ore is from a laterite nickel ore in West Asia, Indonesia, with a Ni content of 1.21%, a Co content of 0.11%, a Fe content of 39.4%, an Al content of 4.08%, a Mn content of 0.78% and a Mg content of 1.86%.

[0066] Example 1

[0067] An embodiment of the method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore of the present invention comprises the following steps:

[0068] S1, introducing a mixed gas of air and SO2 into the lean liquid A at 60°C, the volume ratio of the lean liquid A to the mixed gas is 1:12, the volume ratio of SO2 to O2 in the mixed gas is 1:10.29, and adding a neutralizing agent NaOH at the same time, controlling the pH value of the reaction system to 8.0, and the reaction time is 3h to obtain a manganese precipitate slurry;

[0069] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0070] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate, which is a manganese-containing oxidant.

[0071] Example 2

[0072] An embodiment of the method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore of the present invention comprises the following steps:

[0073] S1, a mixed gas of air and SO2 is introduced into the lean liquid B at 60°C, the volume ratio of the lean liquid B to the mixed gas is 1:15, the volume ratio of SO2 to O2 in the mixed gas is 1:10.29, and a neutralizing agent Ca(OH)2 is added at the same time, the pH value of the reaction system is controlled to 7.8, the reaction time is 3h, and a manganese precipitate slurry is obtained;

[0074] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0075] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate, which is a manganese-containing oxidant.

[0076] Example 3

[0077] An embodiment of the method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore of the present invention comprises the following steps:

[0078] S1, a mixed gas of air and SO2 is introduced into the lean liquid A at 60°C, the volume ratio of the lean liquid A to the mixed gas is 1:12, the volume ratio of SO2 to O2 in the mixed gas is 1:4, and a neutralizing agent NaOH is added at the same time, the pH value of the reaction system is controlled to 7.0, the reaction time is 3h, and a manganese precipitate slurry is obtained;

[0079] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0080] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate, which is a manganese-containing oxidant.

[0081] Example 4

[0082] An embodiment of the method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore of the present invention comprises the following steps:

[0083] S1, introducing a mixed gas of air and SO2 into the lean liquid A at 60°C, the volume ratio of the lean liquid A to the mixed gas is 1:12, the volume ratio of SO2 to O2 in the mixed gas is 1:15, and adding a neutralizing agent NaOH at the same time, controlling the pH value of the reaction system to 7.3, the reaction time is 3h, and obtaining a manganese precipitate slurry;

[0084] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0085] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate, which is a manganese-containing oxidant.

[0086] Example 5

[0087] An embodiment of the method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore of the present invention comprises the following steps:

[0088] S1, introducing a mixed gas of air and SO2 into the lean liquid A at 60°C, the volume ratio of the lean liquid A to the mixed gas is 1:12, the volume ratio of SO2 to O2 in the mixed gas is 1:1.5, and adding a neutralizing agent NaOH at the same time, controlling the pH value of the reaction system to 8.0, and the reaction time is 3h to obtain a manganese precipitate slurry;

[0089] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0090] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate, which is a manganese-containing oxidant.

[0091] Example 6

[0092] An embodiment of the method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore of the present invention comprises the following steps:

[0093] S1, introducing a mixed gas of air and SO2 into the lean liquid A at 60°C, the volume ratio of the lean liquid A to the mixed gas is 1:12, the volume ratio of SO2 to O2 in the mixed gas is 1:25, and at the same time adding a neutralizing agent NaOH, controlling the pH value of the reaction system to 8.0, and the reaction time is 3h to obtain a manganese precipitate slurry;

[0094] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0095] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate, which is a manganese-containing oxidant.

[0096] Comparative Example 1

[0097] A method for treating barren liquid from laterite nickel ore hydrometallurgy, the method comprising the following steps:

[0098] S1, adding a neutralizing agent Ca(OH)2 to the lean solution B at 60°C, controlling the pH value of the reaction system to 7.8, and the reaction time to 3h to obtain a manganese precipitate slurry;

[0099] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0100] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate.

[0101] Comparative Example 2

[0102] An embodiment of a method for preparing a manganese-containing oxidant by hydrometallurgical smelting of barren liquid from laterite nickel ore, the method comprising the following steps:

[0103] S1, introducing air into the lean solution B at 60°C, the volume ratio of the lean solution B to air being 1:15, adding a neutralizing agent Ca(OH)2, controlling the pH value of the reaction system to 7.8, and the reaction time being 3h to obtain a manganese precipitate slurry;

[0104] S2, thickening the manganese precipitate slurry to obtain an underflow slurry;

[0105] S3, filter pressing the underflow slurry to obtain a filter cake containing manganese precipitate, which is a manganese-containing oxidant.

[0106] Performance Testing

[0107] The filter cakes obtained in Examples 1 to 6 and Comparative Examples 1 to 2 were subjected to performance tests. The test methods are as follows. The test results are shown in Table 1.

[0108] Mn precipitation rate: The Mn precipitation rate is calculated by testing the content of manganese ions in the lean solution of laterite nickel ore hydrometallurgy and the content of manganese ions in the concentrated liquid through ICP testing;

[0109] Mn in precipitated slag 4+ / Mn mass percentage: ① Use ICP to test the total Mn content in the precipitated slag; ② Use sulfuric acid solution to quantitatively acid dissolve the precipitated slag, and use ICP to test the Mn dissolution amount, and calculate the proportion of Mn dissolved in the manganese precipitated slag. The Mn that cannot be acid-dissolved in the precipitated slag can be regarded as Mn 4+ , the Mn content in the precipitate can be obtained by using the difference method 4+ / Mn mass percentage.

[0110] Table 1

[0111]

[0112] As shown in Table 1, the precipitation rate of Mn is high when the method described in the embodiment of the present invention is used to treat the barren liquid of laterite nickel ore hydrometallurgy. 4+ / Mn has a high mass ratio, and has good oxidation and precipitation effects; in Comparative Example 1, no oxidant is introduced, and its precipitation effect is poor, and in Comparative Example 2, no SO2 is introduced, and its precipitation rate is also significantly lower than that of the embodiment, and Mn 4+ / Mn accounts for a lower proportion. This result shows that the precipitation effect can be significantly improved by simultaneously introducing an oxidant and adding a neutralizer.

[0113] Application Example 1

[0114] The application of the manganese-containing oxidant of the present invention in the hydrometallurgical process of laterite nickel ore is as follows:

[0115] The manganese-containing oxidant prepared in Example 1, a laterite nickel ore slurry with a solid mass concentration of 40%, and sulfuric acid with a mass concentration of 98% were added to a high-pressure reactor, the dry basis mass ratio of the manganese-containing oxidant to the laterite nickel ore was controlled to be 0.5:100, the acid-ore ratio was 280 kg / t, the reaction pressure was 4.6 MPa, and the reaction was carried out at 255° C. for 1 h to obtain a leaching solution.

[0116] Application Example 2

[0117] The application of the manganese-containing oxidant of the present invention in the hydrometallurgical process of laterite nickel ore is as follows:

[0118] The manganese-containing oxidant prepared in Example 1, a laterite nickel ore slurry with a solid mass concentration of 40%, and sulfuric acid with a mass concentration of 98% were added to a high-pressure reactor, the dry basis mass ratio of the manganese-containing oxidant and the laterite nickel ore was controlled to be 1.0:100, the acid-ore ratio was 280 kg / t ore, the reaction pressure was 4.6 MPa, and the reaction was carried out at 255° C. for 1 h to obtain a leaching solution.

[0119] Application Example 3

[0120] The application of the manganese-containing oxidant of the present invention in the hydrometallurgical process of laterite nickel ore is as follows:

[0121] The manganese-containing oxidant prepared in Example 1, a laterite nickel ore slurry with a solid mass concentration of 40%, and sulfuric acid with a mass concentration of 98% were added to a high-pressure reactor, the dry mass ratio of the manganese-containing oxidant to the laterite nickel ore was controlled to be 1.5:100, the acid-ore ratio was 280 kg / t ore, the reaction pressure was 4.6 MPa, and the reaction was carried out at 255° C. for 1.0 h to obtain a leaching solution.

[0122] Application Example 4

[0123] The application of the manganese-containing oxidant of the present invention in the hydrometallurgical process of laterite nickel ore is as follows:

[0124] The manganese-containing oxidant prepared in Example 1, a laterite nickel ore slurry with a solid mass concentration of 40%, and sulfuric acid with a mass concentration of 98% were added to a high-pressure reactor, the dry mass ratio of the manganese-containing oxidant to the laterite nickel ore was controlled to be 0.1:100, the acid-ore ratio was 280 kg / t ore, the reaction pressure was 4.6 MPa, and the reaction was carried out at 255° C. for 1.0 h to obtain a leaching solution.

[0125] Application Example 5

[0126] The application of the manganese-containing oxidant of the present invention in the hydrometallurgical process of laterite nickel ore is as follows:

[0127] The manganese-containing oxidant prepared in Example 1, a laterite nickel ore slurry with a solid mass concentration of 40% and sulfuric acid with a mass concentration of 98% were added to a high-pressure reactor, the dry basis mass ratio of the manganese-containing oxidant and the laterite nickel ore was controlled to be 6.0:100, the acid-ore ratio was 280 kg / t ore, the reaction pressure was 4.6 MPa, and the reaction was carried out at 255° C. for 1.0 h to obtain a leaching solution.

[0128] Application Example 6

[0129] The application of manganese-containing oxidant in the hydrometallurgical process of laterite nickel ore is as follows:

[0130] S1, adding a laterite nickel ore slurry with a solid mass concentration of 40% and a sulfuric acid with a mass concentration of 98% into a high-pressure reactor, with an acid-ore ratio of 280kg / t and a reaction pressure of 4.6MPa, reacting at 255°C for 1.0h to obtain a leachate;

[0131] S2, adding the manganese-containing oxidant prepared in Example 2 to the leachate, controlling the mass ratio of the dry mass of the manganese-containing oxidant to the mass ratio of the solid in the leachate to be 3.0:100, adding a neutralizing agent limestone to control the reaction pH value to 2.0, reacting at 95° C. for 3 hours, and obtaining a neutralized liquid.

[0132] Application Comparative Example 1

[0133] S1, adding laterite nickel ore slurry with a solid mass concentration of 40% and sulfuric acid with a mass concentration of 98% into a high-pressure reactor, with an acid-ore ratio of 280kg / t and a reaction pressure of 4.6MPa, reacting at 255°C for 1.0h to obtain a leaching solution.

[0134] Performance Testing

[0135] Potassium dichromate chemical titration method and ICP detection method were used to detect Fe in the leachate of application examples 1 to 6 and the reaction solution of comparative example 1. 2+ and the total amount of Fe, Cr 6+ The test was conducted by colorimetry and the test results are recorded in Table 2.

[0136] Table 2

[0137]

[0138] It can be seen from the results of comparative example 1 that if the manganese-containing oxidant is not added in the high-pressure acid leaching, the Fe 2+ It can be seen from Application Examples 1, 2, and 3 that the addition of the oxidant obtained in Example 1 to the high-pressure acid leaching reduces the total Fe concentration in the leaching solution and the Fe 2+ Although the manganese-containing oxidant is added in Application Example 4, the amount of added is insufficient, resulting in Fe 2+ The oxidation effect is poor. Application Example 5 The total concentration of Fe in the leachate and the Fe 2+ The concentration is low, but due to the excessive addition of the manganese-containing oxidant, Cr 6+ ,Cr 6+ Pollute the environment and endanger human health. Reducing agents need to be added in the neutralization and impurity removal process to remove them. Cr should be avoided as much as possible during the leaching process. 6+ Application Example 6: Adding the manganese-containing oxidant obtained in Example 2 to the leachate after high-pressure acid leaching, that is, adding it to the pre-neutralization stage, can also reduce the Fe in the leachate. 2+ The content of manganese-containing oxidant in the present invention is 0.0447 W / m, but it fails to reduce the total Fe content in the leachate. It is necessary to add additional neutralizing agents such as limestone to increase the pH for hydrolysis and iron removal, which will increase the amount of iron slag. In comparison, its oxidation effect in the high-pressure acid leaching process is better. Therefore, the application of the manganese-containing oxidant in the hydrometallurgical process of laterite nickel ore has sufficient advantages over the traditional oxidation iron removal process.

[0139] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those described herein, for example.

[0140] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a manganese-containing oxidant by hydrometallurgical smelting of barren liquid from laterite nickel ore, characterized in that: include: S1, adding an oxidant and a neutralizer to the barren liquid of laterite nickel ore hydrometallurgy to carry out an oxidation manganese precipitation reaction to obtain a manganese precipitation slurry, wherein the oxidant comprises SO2 and O2; S2, performing solid-liquid separation on the manganese precipitated slurry to obtain the manganese-containing oxidant.

2. The method for preparing a manganese-containing oxidant by hydrometallurgical smelting of barren liquid from laterite nickel ore according to claim 1, characterized in that: The volume ratio of the SO2 to the O2 is (1-10):(19-21); the volume ratio of the laterite nickel ore hydrometallurgical lean liquid to the O2 is 1:(0.1-15).

3. The method for preparing a manganese-containing oxidant by hydrometallurgical smelting of barren liquid from laterite nickel ore according to claim 1, characterized in that: The neutralizing agent includes at least one of NaOH, Na2CO3, NaHCO3, KOH, K2CO3, KHCO3, CaO, Ca(OH)2, CaCO3, MgO, Mg(OH)2, and MgCO3.

4. The method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore according to any one of claims 1 to 3, characterized in that: The pH value of the oxidation-precipitation manganese reaction is 4.0-9.

0.

5. The method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore according to claim 4, characterized in that: The temperature of the oxidation manganese precipitation reaction is 30° C. to 90° C., and the time of the oxidation manganese precipitation reaction is 1 h to 10 h.

6. The method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore according to any one of claims 1 to 3, characterized in that: In the S2, solid-liquid separation is performed by thickening; and / or, in the S2, after solid-liquid separation, underflow slurry is obtained, and the underflow slurry is filter-filtered to obtain the manganese-containing oxidant.

7. The method for preparing a manganese-containing oxidant by hydrometallurgical smelting barren liquid of laterite nickel ore according to any one of claims 1 to 3, characterized in that: In the laterite nickel ore wet smelting lean solution, the concentration of Mn is 0.1 g / L to 10 g / L, the concentration of Ni is lower than 1.0 g / L, the concentration of Co is lower than 0.3 g / L, and the concentration of Mg is lower than 15 g / L.

8. Application of a manganese-containing oxidant in a laterite nickel ore hydrometallurgical process, characterized in that: The laterite nickel ore wet smelting process comprises high-pressure acid leaching, pre-neutralization, neutralization to remove iron and aluminum, one-stage nickel and cobalt precipitation, and two-stage nickel and cobalt precipitation. The manganese-containing oxidant is used in the high-pressure acid leaching and / or the pre-neutralization step; the manganese-containing oxidant is prepared by the method described in any one of claims 1 to 7. In the method, the laterite nickel ore wet smelting barren liquid is one or both of the separated liquid obtained after the one-stage nickel and cobalt precipitation and the separated liquid obtained after the two-stage nickel and cobalt precipitation.

9. The use according to claim 8, characterized in that: The manganese-containing oxidant is used in the high-pressure acid leaching step. In the high-pressure acid leaching step, the dry basis mass ratio of the manganese-containing oxidant to the laterite nickel ore is (0.01-5):100; in the dry basis of the laterite nickel ore, the mass content of Ni is 0.5%-2%, the mass content of Co is 0.05%-0.2%, the mass content of Fe is 20%-50%, the mass content of Al is 1%-10%, the mass content of Mn is 0.5%-1.5%, and the mass content of Mg is 0.1%-10%.

10. The use according to claim 9, characterized in that: The high pressure pickling step includes at least one of the following features: (1) Acid-ore ratio is 200kg / t~500kg / t; (2) The reaction temperature is 240°C to 280°C; (3) The reaction time is 0.5h to 2h; (4) The reaction pressure is 4 MPa to 6 MPa.

Images