AU2019310838B2

AU2019310838B2 - Method for homogeneous precipitation separation of nickel, cobalt and manganese from laterite nickel ore acid leaching solution

Info

Publication number: AU2019310838B2
Application number: AU2019310838A
Authority: AU
Inventors: Yongqiang Chen; Yong DAN; Changhao JIN; Baozhong MA; Chengyan Wang; Lin Zhao; Peng Zhao
Original assignee: Sichuan Shunying Power Battery Material Co Ltd
Current assignee: Sichuan Shunying Power Battery Material Co Ltd
Priority date: 2018-07-24
Filing date: 2019-06-24
Publication date: 2022-03-10
Anticipated expiration: 2039-06-24
Also published as: CN109022823A; CU24672B1; AU2019310838A1; CN109022823B; CU20200059A7; PH12020551383A1; WO2020019918A1

Abstract

Disclosed is a method for the homogeneous precipitation separation of nickel, cobalt and manganese from a laterite nickel ore acid leaching solution, wherein the present invention belongs to the technical field of the comprehensive utilization of complex multi-metal resources. The method comprises: formulating a sodium hydroxide solution or finely ground calcium oxide or magnesium oxide into a slurry as a precipitating agent; conveying the precipitating agent to a homogeneous reactor via a pipe provided with a rate control device and installing a refiner at an outlet end to refine the precipitating agent; conveying an acid solution containing nickel, cobalt and manganese to the homogeneous reactor via a pipe provided with a rate control device and installing an atomizer at an outlet end to atomize the acid solution, wherein the controlled rate atomized nickel-cobalt-manganic acid solution and the rate-control refined precipitating agent are homogeneously reacted in the homogeneous reactor to obtain a post-reaction slurry; and filtering the post-reaction slurry to obtain a liquid remaining after nickel-cobalt precipitation and a sand-like nickel-cobalt-manganese residue. The method has a simple process, a high operability, a low cost and convenient industrial production, can realize high-efficiency separation of nickel, cobalt and manganese from a laterite nickel ore acid leaching liquid, and has broad application prospects.

Description

Specification

Method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution

Technical Field The present invention relates to the technical field of comprehensive utilization of complex polymetallic resources, and in particular to a method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution.

Background Art Nickel is an important strategic material, and is mainly used in producing stainless steel, alloy steel, special alloy and the like. Nickel ore resources are divided into two types, i.e., nickel sulfide ore and nickel oxide ore, wherein the rock mass of the nickel oxide ore appears to be red because iron in the ore is oxidized due to weathering, and thus the nickel oxide ore is also known as laterite-nickel ore. Nowadays, since the need for nickel in the market is increasing, and nickel sulfide ore resources with high grade of nickel are gradually depleted, the extraction of nickel from the laterite-nickel ore attracts more and more attentions. At present, a wet process for refining a laterite-nickel ore mainly includes an atmospheric pressure acid leaching process and a pressurized acid leaching process. In either process, nickel finally occurs in the laterite-nickel ore acid leaching solution. After removing iron and aluminum from the laterite-nickel ore acid leaching solution, valuable metals of nickel, cobalt and manganese are mainly enriched in the leaching solution, and can be recovered by a precipitation method. However, in existed methods, the speeds of the precipitation and the filtration are low, and the precipitation residue obtained after filtration has a relatively large water content, with a certain amount of magnesium entrained, directly resulting in increased loss rates of nickel, cobalt and manganese. In view of the shortcomings existed in the above process for precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore solution with iron and aluminum removed, new technologies suitable for neutralizing and precipitating nickel, cobalt and manganese have been investigated recently. CN Patent No. CN101525690 discloses a method for separating and recovering nickel, cobalt, magnesium, iron and silicon from a laterite-nickel ore. In the technical solution thereof, nickel carbonate is precipitated with magnesite powder, and the solution obtained after precipitation is concentrated and crystallized to obtain magnesium sulfate heptahydrate. However, this method does not take the problem of comprehensive recovery of cobalt and manganese into consideration, leading to low recovery of valuable metals. CN Patent No. CN1O1323908 discloses a method for recovering cobalt and nickel from a manganese-cobalt residue. In the technical solution thereof, the manganese-cobalt residue is cured with sulfuric acid to obtain a cobalt-nickel solution, then cobalt and nickel are deeply purified and separated by extraction according to a conventional process. The process is complex, the cobalt-nickel residue obtained after filtration has a relatively high water content, and the recovery of manganese is not taken into consideration. CN Patent No. CN102268537A discloses a method for extracting cobalt and nickel from a laterite-nickel ore. In the technical solution thereof, nickel and cobalt are converted into nickel hydroxide and cobalt hydroxide through alkali neutralization, or converted into nickel sulfide and cobalt sulfide through sulfide precipitation, or the aqueous solution is directly used for electrolysis to produce metal nickel or metal cobalt. This method has a drawback that some magnesium hydroxide will be entrained in the resultant nickel hydroxide and cobalt hydroxide. CN Patent No. CN101338374 discloses a method for extracting nickel and cobalt from a laterite-nickel ore. After removing iron from the laterite-nickel ore acid leaching solution, a sulfide precipitant is added, and the precipitation results in a nickel-cobalt rich sulfide. However, magnesium sulfide slightly soluble in water will still be entrained in the precipitate, and thus the subsequent purification procedure is difficult. In summary, in the above existed technologies, modifications on the process for extracting nickel, cobalt and manganese from a laterite-nickel ore solution with iron and aluminum removed still have disadvantages such as strict process conditions, low metal recovery, and difficult subsequent purification process due to ease of entraining metal magnesium, and cannot well achieve separation and recovery of valuable elements of nickel, cobalt and manganese in the laterite-nickel ore.

Summary In order to solve the technical problems occurred in the above existed technologies, the present invention provides a method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution. An object of the present invention is to efficiently separate nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution with iron and aluminum deeply removed. The object is achieved by a "precipitant preparation - precipitant refining at a controlled speed atomization of an acid solution containing nickel, cobalt and manganese at a controlled speed - homogeneous system reaction - separation by filtration" technical route, wherein the precipitation rates of both nickel and cobalt reach 99% or more, and the precipitation rate of manganese is more than 85%, thereby well achieving the separation and recovery of nickel, cobalt and manganese. The process flow is simple and the production cost is low, so the method is convenient for industrialization promotion. A method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution, comprising: Step I: precipitant preparation: using a slurry formulated by adding a proportion of water to calcium oxide/magnesium oxide and mixing them homogeneously, or a sodium hydroxide aqueous solution with a concentration as a precipitant for nickel, cobalt and manganese; Step II: precipitant refining at a controlled speed: delivering the precipitant to a homogeneous reactor through a pipe having a speed control device, with a refining device mounted at an outlet end, in order to add the precipitant refined at a controlled speed into the reactor; Step III: atomization of an acid solution containing nickel, cobalt and manganese at a controlled speed: delivering the acid solution containing nickel, cobalt and manganese to the homogeneous reactor through a pipe having a speed control device, with an atomizer mounted at an outlet end, in order to add the acid solution containing nickel, cobalt and manganese atomized at a controlled speed into the reactor; Step IV: homogeneous system reaction: adding the material of Step II and the solution of Step III into the reactor, heating and stirring them, and adjusting a pH to a constant value to form a homogeneous system, to convert nickel, cobalt and manganese into a precipitate; and Step V: separation by filtration: separating a slurry obtained after the neutralization and precipitation in Step IV by filtration to obtain a solution with nickel, cobalt and manganese removed and a sand-like nickel-cobalt-manganese residue, wherein the filtration speed is increased by 10-20 times as compared to a conventional method.

Further, the precipitant formulated has a concentration of 10%-40% CaO/MgO for the slurry, or 50-150 g/L for the NaOH solution, wherein both calcium oxide and magnesium oxide have a particle size of less than 74 tm after fine grinding. Further, an adding speed of the precipitant in Step II is strictly controlled according to requirement for reaction, and the precipitant refining is achieved by mounting the refining device at the outlet end, wherein the refining device is a porous sprayer and has a pore diameter of 100-150 pm. Further, the acid solution containing nickel, cobalt and manganese treated comprises 2-8 g/L of Ni, 0.3-3 g/L of Co, 2-8 g/L of Mn, 0.5-5 g/L of Ca, 1-20 g/L of Mg, and an anion in the solution being one or more selected from NO3, Cl or SO42 Further, an adding speed of the acid solution containing nickel, cobalt and manganese treated in Step III is strictly controlled according to requirement for reaction, and the atomization of the laterite-nickel ore solution with iron and aluminum removed is achieved by mounting the atomizer at the outlet end. Further, for the homogeneous system reaction in Step IV, the pH is controlled in a range of 6.8-8.3 and maintained constant at a certain value, and further, a reaction temperature is 30-80°C, a reaction time is 0.5-3 h, and a stirring speed is 50-200 rpm, wherein the temperature is kept stable during the reaction. It can be seen from the above technical solutions provided in the present invention that the present invention provides a method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution. By using a "precipitant preparation - precipitant refining at a controlled speed - atomization of an acid solution containing nickel, cobalt and manganese at a controlled speed - homogeneous system reaction - separation by filtration" process route, the object of separating and purifying nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution is achieved. The process flow is simple, the equipment investment is low, and the operation is convenient, so the method can be put into industrial production in large scale. The merit of the present invention lies in that the precipitant and the acid solution containing nickel, cobalt and manganese are added through refining and atomization respectively, and the adding speeds thereof are strictly controlled according to the molar ratio of materials required for the precipitation reaction, so as to control the reaction system to maintain constant at a certain pH, thereby achieving a homogeneous system reaction. As compared to the existed technologies, the method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution provided in the present invention at least has the following advantages. (1) The nickel-cobalt residue obtained by a homogeneous system precipitation method appears to be sand-like, while the nickel-cobalt residue obtained by a conventional precipitation method appears to be colloidal, such that the present technology has an ore slurry filtration speed increased by 10-20 times as compared to a conventional precipitation method, and is convenient for industrial production. (2) The water content of the residue obtained after filtration is reduced from original about 60% to 30% or less, greatly reducing the amount of magnesium entrained in the residue. (3) By using charging modes of atomization and refining, a homogeneous system reaction is achieved, which can prevent the reaction system from being partially too alkaline, thereby reducing the entrainment of magnesium.

Brief Description of Drawings In order to more clearly describe technical solutions of embodiments of the present invention, drawing(s) to be used in describing the embodiments will be briefly introduced below. Obviously, the drawing(s) as described below is/are only some of the embodiments of the present invention. An ordinary person skilled in the art can also obtain other drawings according to the drawing(s) without any inventive effort. Fig. 1 show the method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore solution with iron and aluminum removed provided in an embodiment of the present invention.

Detailed Description The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the drawing(s) of the embodiments. Obviously, the embodiments as described are only a portion of, but not all of, the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by an ordinary person skilled in the art without any inventive effort fall within the protection scope of the present invention. In order to more clearly exhibit the technical solutions provided in the present invention and the technical effects produced, the method provided in the present invention will be described in detail below by way of specific examples. Example 1 As shown in Fig. 1, the method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution comprises the following steps. 100 kg of calcium oxide was formulated, and 400 kg of water was added thereto. The mixture was fully stirred uniformly to produce a calcium oxide emulsion as a precipitant. The precipitant has a slurry concentration of 20%, was delivered through a pipe having a speed control device, and was added into a homogeneous reactor through a refining device at an outlet end. Meanwhile, an acid solution containing nickel, cobalt and manganese was also delivered through a pipe having a speed control device, and added into the homogeneous reactor through an atomizer at an outlet end. The acid solution containing nickel, cobalt and manganese atomized at a controlled speed and the precipitant refined at a controlled speed were homogeneously reacted in the homogeneous reactor. The pH of the homogeneous system reaction was 6.8, the reaction temperature was 30°C, the reaction time was 3 h, and the stirring speed was 100 rpm. The pH and temperature were kept constant during the reaction. According to requirement for the reaction, the adding speeds of the acid solution containing nickel, cobalt and manganese and the precipitant were strictly controlled, to keep the reaction system balanced and stable. Finally, the post-reaction slurry was delivered to a filter through a pipe for filtration to obtain a solution with nickel, cobalt and manganese removed and a sand-like nickel-cobalt-manganese residue. The precipitation rates of nickel and cobalt were 99.6% and 99.2% respectively, and the precipitation rate of manganese was 85.6%. Example 2 The method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution comprises the following steps. 200 kg of calcium oxide was formulated, and 450 kg of water was added thereto. The mixture was fully stirred uniformly to produce a calcium oxide emulsion as a precipitant. The precipitant has a slurry concentration of 30.7%, was delivered through a pipe having a speed control device, and was added into a homogeneous reactor through a refining device at an outlet end. Meanwhile, an acid solution containing nickel, cobalt and manganese was also delivered through a pipe having a speed control device, and added into the homogeneous reactor through an atomizer at an outlet end. The acid solution containing nickel, cobalt and manganese atomized at a controlled speed and the precipitant refined at a controlled speed were homogeneously reacted in the homogeneous reactor. The pH of the homogeneous system reaction was 7.2, the reaction temperature was 50°C, the reaction time was 3 h, and the stirring speed was 120 rpm. The pH and temperature were kept constant during the reaction. According to requirement for the reaction, the adding speeds of the acid solution containing nickel, cobalt and manganese and the precipitant were strictly controlled, to keep the reaction system balanced and stable. Finally, the post-reaction slurry was delivered to a filter through a pipe for filtration to obtain a solution with nickel, cobalt and manganese removed and a sand-like nickel-cobalt-manganese residue. The precipitation rates of nickel and cobalt were 99.2% and 99.4% respectively, and the precipitation rate of manganese was 87.3%. Example 3 The method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution comprises the following steps. 80 g/L sodium hydroxide aqueous solution was formulated as a precipitant. The precipitant was delivered through a pipe having a speed control device, and was added into a homogeneous reactor through a refining device at an outlet end. Meanwhile, an acid solution containing nickel, cobalt and manganese was also delivered through a pipe having a speed control device, and added into the homogeneous reactor through an atomizer at an outlet end. The acid solution containing nickel, cobalt and manganese atomized at a controlled speed and the precipitant refined at a controlled speed were homogeneously reacted in the homogeneous reactor. The pH of the homogeneous system reaction was 8.0, the reaction temperature was 60°C, the reaction time was 2 h, and the stirring speed was 150 rpm. The pH and temperature were kept constant during the reaction. According to requirement for the reaction, the adding speeds of the acid solution containing nickel, cobalt and manganese and the precipitant were strictly controlled, to keep the reaction system balanced and stable. Finally, the post-reaction slurry was delivered to a filter through a pipe for filtration to obtain a solution with nickel, cobalt and manganese removed and a sand-like nickel-cobalt-manganese residue. The precipitation rates of nickel and cobalt were 99.2% and 99.4% respectively, and the precipitation rate of manganese was 87.3%. Example 4 The method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution comprises the following steps. 200 kg of magnesium oxide was formulated, and 450 kg of water was added thereto. The mixture was fully stirred uniformly to produce a calcium oxide emulsion as a precipitant. The precipitant has a slurry concentration of 30.7%, was delivered through a pipe having a speed control device, and was added into a homogeneous reactor through a refining device at an outlet end. Meanwhile, an acid solution containing nickel, cobalt and manganese was also delivered through a pipe having a speed control device, and added into the homogeneous reactor through an atomizer at an outlet end. The acid solution containing nickel, cobalt and manganese atomized at a controlled speed and the precipitant refined at a controlled speed were homogeneously reacted in the homogeneous reactor. The pH of the homogeneous system reaction was 7.0, the reaction temperature was 60°C, the reaction time was 2.5 h, and the stirring speed was 50 rpm. The pH and temperature were kept constant during the reaction. According to requirement for the reaction, the adding speeds of the acid solution containing nickel, cobalt and manganese and the precipitant were strictly controlled, to keep the reaction system balanced and stable. Finally, the post-reaction slurry was delivered to a filter through a pipe for filtration to obtain a solution with nickel, cobalt and manganese removed and a sand-like nickel-cobalt-manganese residue. The precipitation rates of nickel and cobalt were 99.7% and 99.1% respectively, and the precipitation rate of manganese was 85.6%. Example 5 The method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution comprises the following steps. 100kg of magnesium oxide was formulated, and 300kg of water was added thereto. The mixture was fully stirred uniformly to produce a calcium oxide emulsion as a precipitant. The precipitant has a slurry concentration of 25%, was delivered through a pipe having a speed control device, and was added into a homogeneous reactor through a refining device at an outlet end. Meanwhile, an acid solution containing nickel, cobalt and manganese was also delivered through a pipe having a speed control device, and added into the homogeneous reactor through an atomizer at an outlet end. The acid solution containing nickel, cobalt and manganese atomized at a controlled speed and the precipitant refined at a controlled speed were homogeneously reacted in the homogeneous reactor. The pH of the homogeneous system reaction was 8.3, the reaction temperature was 80°C, the reaction time was 3 h, and the stirring speed was 200 rpm. The pH and temperature were kept constant during the reaction. According to requirement for the reaction, the adding speeds of the acid solution containing nickel, cobalt and manganese and the precipitant were strictly controlled, to keep the reaction system balanced and stable. Finally, the post-reaction slurry was delivered to a filter through a pipe for filtration to obtain a solution with nickel, cobalt and manganese removed and a sand-like nickel-cobalt-manganese residue. The precipitation rates of nickel and cobalt were 99.4% and 99.7% respectively, and the precipitation rate of manganese was 87.2%. In conclusion, the present invention well achieves precipitation separation of nickel, cobalt and manganese from the laterite-nickel ore acid leaching solution. The foregoings are particular embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Variations or replacement, which can be readily envisaged by those skilled in the art within the technical scope as disclosed in the present invention, should fall within the protection scope of the present invention. Therefore, the protection scope of the present invention is defined by the protection scopes of the appended claims.

Claims

1. A method for homogeneous precipitation separation of nickel, cobalt and manganese from a laterite-nickel ore acid leaching solution, characterized by comprising: Step I: precipitant preparation: using a slurry formulated by adding a proportion of water to calcium oxide/magnesium oxide and mixing them homogeneously, or a sodium hydroxide aqueous solution with a concentration as a precipitant for nickel, cobalt and manganese; the precipitant formulated has a concentration of 10%-40% CaO/MgO for the slurry, or 50-150 g/L for the NaOH solution, wherein both calcium oxide and magnesium oxide have a particle size of less than 74 pm after fine grinding;

Step II: precipitant refining at a controlled speed: delivering the precipitant to a homogeneous reactor through a pipe having a speed control device, with a refining device mounted at an outlet end, in order to add the precipitant refined at a controlled speed into the reactor; the adding speed of the precipitant is strictly controlled according to requirement for reaction, and the precipitant refining is achieved by mounting the refining device at the outlet end, wherein the refining device is a porous sprayer and has a pore diameter of 100-150 pm; Step III: atomization of an acid solution containing nickel, cobalt and manganese at a controlled speed: delivering the acid solution containing nickel, cobalt and manganese to the homogeneous reactor through a pipe having a speed control device, with an atomizer mounted at an outlet end, in order to add the acid solution containing nickel, cobalt and manganese atomized at a controlled speed into the reactor; the acid solution containing nickel, cobalt and manganese treated comprises: 2-8 g/L of Ni, 0.3-3 g/L of Co, 2-8 g/L of Mn, 0.5-5 g/L of Ca, 1-20 g/L of Mg, and an anion in the solution being one or more selected from NO3-, Cl- or S0 4 2 -; an adding speed of the acid solution containing nickel, cobalt and manganese treated is strictly controlled according to requirement for reaction, and the atomization of the laterite-nickel ore solution with iron and aluminum removed is achieved by mounting the atomizer at the outlet end. Step IV: homogeneous system reaction: adding the material of Step II and the solution of Step III into the reactor, heating and stirring them, and adjusting the pH is controlled in a range of 6.8-8.3 and maintained constant at a certain value to form a homogeneous system, to convert nickel, cobalt and manganese into a precipitate; wherein, a reaction temperature is 30 800C, a reaction time is 0.5-3 h, and a stirring speed is 50-200 rpm, wherein the temperature is kept stable during the reaction; Step V: separation by filtration: separating a slurry obtained after the neutralization and precipitation in Step IV by filtration to obtain a solution with nickel, cobalt and manganese removed and a sand-like nickel-cobalt manganese residue.