KR100728795B1 - Nickel metal and process for producing the same - Google Patents

Abstract

The present invention relates to a method for producing nickel metal and to high purity nickel metal which can increase nickel oxide reduction efficiency and realize a reduction in energy and cost. The method includes performing a contact reaction between nickel oxide as a raw material and a reducing gas to produce nickel metal from nickel oxide, the contact reaction having stoichiometric coexistence of a very small amount of sodium-containing compound. Is carried out under. The content of sodium in the nickel metal produced by the above method is controlled to at most 0.13% by weight in the amount of sodium atoms based on the amount of nickel metal.

Nickel metal, nickel oxide, reduction

Description

Nickel metal and process for producing same

The present invention relates to a nickel metal and a method for producing the same. More specifically, the present invention relates to a method for producing nickel metal, which can produce nickel metal having a low content of sodium as an impurity and a highly efficient nickel metal at low cost.

Several methods of making metals by contacting solid metal oxides with a reducing gas have been proposed and in practice used. For example, ammonia, carbon monoxide, hydrogen or natural gas or propane gas containing them is used as the reducing gas.

The methods are useful in some cases, on the other hand, because of the various problems that inhibit the reduction reactions encountered in the manufacture of the metal, the intended metal cannot be produced effectively. For example, in the step of reducing iron oxide with a gas, a dense layer of metal iron is formed to reduce the reaction rate. Because of this phenomenon, a significant decrease in reaction rate sometimes occurs during the reaction. This phenomenon was discovered when nickel oxide was used as raw material.

A method for overcoming the disadvantages associated with the formation of a dense metal layer has been proposed. In this method, calcium oxide (CaO) is added. Investigations of the reduction reactions of wistite and nickel oxide have found that mixing of CaO enhances the reduction reaction. See, for example, Yoshiaki Iguchi, "Additional Effect of CaO or MgO on Reduction of Nickel Oxide Pellets." Journal of the Japan Institute of Metal, Vol. 46, No. 7, pp. According to 696-703 (1892), a CaO concentration of 1.5 mol% provides the maximum reduction rate.

This CaO concentration is 1.1% by weight of CaO based on the weight of nickel oxide and about 1% by weight ratio of calcium and product nickel. Given the production of nickel at commercial capacity, the addition of as much as 1% CaO is undesirable in terms of product quality as well as cost.

Methods of treating nickel oxide ore including adding certain compounds have been proposed in, for example, Japanese Patent Laid-Open Nos. 253520/1991 and 111840/1990. The amount (weight) of the additives used in the method exceeds 1% based on the target raw material. Therefore, even if the content of nickel in the light is 2.5% higher than the amount of conventional light, the amount of the additive is as high as 40% based on nickel. Thus, in these methods, the cost of the additive itself is enormous. In addition, the additives used are present in the product in significant amounts as impurities. For this reason, these methods are by no means effective.

In addition, in a conventional method for producing nickel metal, solid nickel oxide is melted, and in this state, it reacts with a reducing agent, and disadvantageously consumes a lot of energy.

It is therefore an object of the present invention to solve the above problems of the prior art and to provide a method for producing nickel metal at low cost with high efficiency. That is, it is an object of the present invention to provide a method for producing nickel metal, which significantly improves energy consumption and contributes to the improvement of the environment, by adding very small amounts of sodium to provide high purity nickel metal. It is possible to improve reaction steps that are prohibited and inefficient in the prior art.

The inventors have conducted extensive and intensive studies to achieve the above object, and as a result, have unexpectedly found that the above object can be achieved by adding a very small amount of sodium stoichiometrically to the subject nickel oxide. This has completed the present invention. In addition, the inventors have studied various additives that can enhance the reaction in a method for producing nickel metal from nickel oxide using a reducing agent. As a result, it was found that the reaction rate can be increased significantly by adding stoichiometrically very small amounts of sodium-containing additives.

According to one aspect of the invention, there is provided a method for producing a nickel metal comprising the step of performing a contact reaction between nickel oxide and a reducing gas as a raw material to produce a nickel metal from the nickel oxide, the contact reaction is chemical It is stoichiometrically carried out in the presence of relatively very small amounts of sodium-containing compounds.

In this preparation method, preferably, the amount of sodium-containing compound as coexistent material is 0.001% to 0.1% by weight in the amount of sodium atoms based on the amount of nickel oxide.

Also in the production process, preferably, the sodium-containing compound is selected from the group consisting of sodium carbonate, sodium hydroxide, sodium chloride, sodium hydrogen sulfite and sodium silicate (water glass).

In addition, in the production method, preferably, the reducing gas contains a material selected from hydrogen, carbon monoxide, ammonia and methanol.

In addition, in the production process, preferably, the nickel oxide is in the form having a diameter of at most 5 mm, more preferably at most 3 mm.

In addition, in the production method, preferably, the contact reaction between the nickel oxide and the reducing gas is performed at a temperature of 600 to 1000 ° C.

According to another aspect of the present invention, there is provided a nickel metal produced by the above production method, wherein the content of sodium in the nickel metal produced by the above method is at most 0.13 in the amount of sodium atoms based on the amount of the nickel metal. It is adjusted by weight%.

In this nickel metal, preferably, the content of sodium in the nickel metal produced by the method is controlled to at most 0.0025% by weight in the amount of sodium atoms based on the amount of the nickel metal.

According to the preparation method of the present invention, the production of nickel metal from nickel oxide by the contact reaction between nickel oxide and reducing gas is carried out in the presence of a relatively small amount of sodium-containing compound, thereby producing a high purity nickel metal having a low residual sodium content. Can be prepared.

In addition, the presence of very small amounts of sodium-containing compounds allows the reduction of nickel oxide to proceed quickly and satisfactorily. Thus, even when the treatment is carried out at a temperature below the temperature adopted in the prior art or at a treatment time shorter than the treatment time adopted in the prior art, high purity nickel metal can be produced in high yield.

Thus, the energy and cost for the production of nickel metal can be significantly reduced.

1 is a graph showing the weight loss of nickel oxide observed by the reduction reaction of the nickel oxide method of Example 1;

2 is a graph showing the weight loss of nickel oxide observed by the reduction reaction of the nickel oxide method of Comparative Example 1;

3 is a graph showing the weight loss of nickel oxide observed by the reduction reaction of the nickel oxide method of Example 2 and Comparative Example 2;

4 is a graph showing the weight loss of nickel oxide observed by the reduction reaction of the nickel oxide method of Example 3 and Comparative Example 3;

5 is a graph showing the weight loss of nickel oxide observed by the reduction reaction of the nickel oxide method of Example 4 and Comparative Example 4;

6 is a graph showing the weight loss of nickel oxide observed by the reduction reaction of the nickel oxide method of Example 5 and Comparative Example 5;

7 is a graph showing the weight loss of nickel oxide observed by the reduction reaction of the nickel oxide method of Example 6 and Comparative Example 6;

8 is a graph showing changes in the amount of CO gas and CO ₂ gas in the exhaust gas around the outlet of the fluidized bed of Example 7 and Comparative Example 7. FIG.

The present invention will be described in more detail.

Basic chemical reaction formulas for metals prepared from metal oxides

The production of the metal (M) from the metal oxide (MnOm) can be basically expressed by the following chemical reaction formula.

MnOm + C or H = nM + CO ₂ or H ₂ O

MnOm + CO = nM + CO ₂

Importance of the Invention

In the production process according to the above scheme, various reaction disorders occur and often make the method ineffective. In many cases, fossil fuels, for example, solid materials such as coal and coke, liquid materials such as fuel oil and diesel, and gaseous materials such as natural gas and hydrogen are used as reducing agents. Most of these materials contain carbon. This means that when the reaction is ineffective, the amount of carbon and hydrogen that remain unreacted increases. It should also be noted that in the reduction process, carbon dioxide is finally produced. Treatment of carbon dioxide and hydrogen-containing off-gases and carbon dioxide that remain unreacted is not easy and inexpensive. In addition, increasing the reaction temperature and extending the reaction time for the purpose of increasing the purity of the metal should be avoided in terms of energy consumption and cost.

Considering the recent global environmental issues, the effect of very effective reduction methods on environmental improvement is enormous. Under these circumstances, the present invention can improve the efficiency of the method for producing nickel metal. Therefore, the present invention is inexpensive and at the same time very advantageous for energy saving and environmental improvement.

Nickel oxide as raw material

In the present invention, nickel oxide may be any one as a raw material for use in producing nickel metal. In the present invention, for example, nickel oxide prepared from oxide nickel or nickel sulfide can be used.

Nickel oxide used in the present invention mainly consists of nickel (Ni) and oxygen (O) atoms, for example cobalt (Co), copper (Cu), iron (Fe) and other (eg magnesium (Mg)). ) May further contain atoms. The form and content of atoms other than nickel and oxygen may vary depending on the source of nickel oxide, the route to obtaining nickel oxide, and the method of preparation.

The shape and size of the nickel oxide may be appropriately selected in consideration of the specific content of the contact reaction between the nickel oxide and the reducing gas, the addition of the sodium-containing compound coexisting in the reduction reaction, and the characteristics and working characteristics of the embodiment and the reaction apparatus. Can be.

In the present invention, particulate nickel oxide having a particle diameter of at most 5 mm, preferably at most 3 mm can be used. In general, smaller diameter particles are more beneficial in terms of reaction rate. However, particles with excessively small particles can adversely increase the scattering loss of the particles. Thus, when the contact reaction between nickel oxide and the reducing gas is carried out in such a manner that the nickel oxide particles are placed in the reducing gas stream, the diameter of the nickel oxide particles is preferably 0.1 to 5 mm, particularly preferably 0.1 to 3 mm. On the other hand, when the contact reaction between nickel oxide and the reducing gas is carried out in such a manner that the fluidized bed is formed using particles containing nickel oxide and the contacting reaction is carried out in the fluidized bed, the diameter of the nickel oxide particles is 0.1 to 2 mm, preferably Preferably 0.1 to 1 mm.

<Reduction gas>

In the present invention, any reducing gas may be used as long as the reducing gas can reduce nickel oxide to nickel metal. For example, in the present invention, it is preferable to use a reducing gas containing at least one substance selected from the group consisting of hydrogen, carbon monoxide, ammonia and methanol. In the present invention, hydrogen and carbon monoxide are particularly preferred.

In the present invention, the reducing gas comprises (i) a pure gas consisting essentially of one reducing compound, (ii) a mixture of a plurality of reducing compounds, or (iii) one or a plurality of reducing compounds and one or a plurality of non-reducing compounds. It may be a configured gas. For example, natural gas and propane gas containing carbon monoxide and hydrogen can be used as reducing gas (iii) in the present invention and are preferred embodiments of the reducing gas.

In the present invention, the reducing gas must be a gas under temperature and pressure conditions during the contact reaction with nickel oxide. As long as this condition is satisfied, the reducing gas does not always need to be a gas when supplied to the reaction apparatus.

In this respect, compounds which significantly degrade the purity or grade of nickel metal due to inhibition of the reduction of nickel oxide or formation of metal nickel, reaction with the resulting nickel metal or retention in the resulting nickel metal, of the resulting nickel metal It should be noted that, for example, sulfur and chlorine are preferably not contained in the reducing gas, such as compounds that limit their use, properties, or the like that interfere with the durability and stable operation of the manufacturing apparatus.

Sodium-containing compound

In the present invention, any suitable sodium-containing compound may be used. Examples of preferred sodium-containing compounds in the present invention include sodium carbonate (so-called "soda water"), sodium hydroxide, sodium chloride, sodium bisulfite, sodium bicarbonate, sodium chlorate, bleach and sodium silicates (primarily Na ₂ O, SiO ₂ and H ₂ O). Is selected from the group consisting of Among these, sodium carbonate and sodium bicarbonate are preferable.

The sodium-containing compound is preferably added in a solution to facilitate the addition of the sodium-containing compound. Thus, the sodium-containing compound is preferably dissolved in water. In this case, the dispersibility of the additive for uniformly improving the reaction can be improved. If possible, the content of harmful elements such as sulfur and chlorine is minimized, and sodium-containing compounds preferably remove these harmful elements.

In the present invention, the required amount of the sodium-containing compound added is very small, and the addition of 0.002% by weight of the sodium-containing compound in the amount of sodium atoms relative to the amount of nickel oxide satisfies the intended effect. This effect can be obtained when the amount of the sodium-containing compound added is 0.001%. When the amount of the sodium-containing compound added is 0.001 to 0.01%, the sodium-containing compound has little or no effect on the quality of the nickel metal and neglects additives contained as impurities in the product. When there is no strict limit on the impurity, the amount of additive can increase to 0.05%. In addition, when there is no limit to the sodium contained in the product, the amount of sodium-containing compound added may be 0.1%. However, the addition of sodium-containing compounds in an amount exceeding 0.1% is not inexpensive and is undesirable in terms of quality.

Thus, in the present invention, the amount of sodium-containing compound based on sodium atoms is preferably 0.001% to 0.1% by weight, particularly preferably 0.002% to 0.005% by weight based on the amount of nickel oxide.

When the sodium-containing compound is a solid, preferably, in view of ensuring good contact between the nickel oxide and the reducing gas, the sodium-containing compound is for example particles of 0.1 to 5 mm, preferably 0.1 to 1 mm. Used in the form of fine powder with a diameter.

In this respect, compounds which significantly degrade the purity or grade of nickel metal due to inhibition of the reduction of nickel oxide or formation of metal nickel, reaction with the resulting nickel metal or retention in the resulting nickel metal, of the resulting nickel metal It should be noted that, for example, sulfur and chlorine are preferably not contained in the reducing gas, such as compounds that limit their use, properties, or the like that interfere with the durability and stable operation of the manufacturing apparatus.

<Processing condition>

The conditions under which the contact reaction between nickel oxide and the reducing gas is carried out to produce nickel metal from nickel oxide are, for example, the characteristics of nickel oxide, the form of the reducing gas, the form and properties of the sodium-containing compound coexisting in the reduction reaction, It may be appropriately determined in consideration of the reaction apparatus, the operating state of the reaction apparatus, and the required purity of the nickel metal produced.

The contact reaction between nickel oxide and the reducing gas can be carried out by the method in which the nickel oxide is located in the reducing gas stream or by the method in which the fluidized bed is formed using nickel oxide particles and the contact reaction between nickel oxide and the reducing gas is carried out in the fluidized bed. do.

The addition of the sodium-containing compound is most preferred for the catalytic reaction transition between nickel oxide and the reducing gas, and the required amount of the sodium-containing compound is premixed in the nickel oxide. However, optionally, after initiating the catalytic reaction between the nickel oxide and the reducing gas, the sodium-containing compound may be supplied to the catalytic reaction system.

A treatment temperature of 1000 ° C. satisfies the contact reaction between the nickel oxide and the reducing gas in the presence of the sodium-containing compound. The reaction proceeds effectively at temperatures of 900 ° C or 700 ° C. As long as the intended grade of the product nickel metal can be realized, the choice of temperature of 600 ° C. is possible even if the reaction rate is rather low. Therefore, in the present invention, it is preferable that the contact reaction between nickel oxide and the reducing gas can be carried out at a temperature of 600 ° C to 1000 ° C, particularly preferably 800 ° C to 1000 ° C. The treatment temperature may not always remain constant and may change during the treatment.

<Nickel metal>

In the process for producing nickel metal according to the invention, when very small amounts of sodium compounds are present in the reaction system, the reduction of nickel oxide proceeds quickly and satisfactorily. Thus, even when compared to the prior art, even when lower treatment temperatures or shorter treatment times are used, very high purity nickel metals with low residual sodium content can be produced in high yield. For example, according to the invention, high purity nickel metals having a sodium content of at most 0.01% by weight, in particular at most 0.0025% by weight can be produced.

In the case of other conventional nickel metals, these nickel metals can be produced on their own or for a variety of uses after appropriate post-treatment, for example, purification.

The reason why the unexpected improvement in the yield of nickel metal can be realized stoichiometrically by the addition of very small amounts of sodium is not yet fully understood.

However, this reason is considered as follows.

Example

Example  One

80 mg of nickel oxide was weighed out. 0.002% by weight of NaCO ₃ was added in the amount of sodium atoms based on the amount of nickel oxide and mixed with nickel oxide. The mixture was charged to a quartz crucible and the crucible was transferred to a TG (thermal-gravity analysis) apparatus that heated the components of the crucible to the desired temperatures (ie, 900 ° C, 800 ° C, 700 ° C and 600 ° C). Then, the reduction reaction of nickel oxide was performed while supplying hydrogen with reducing gas at a rate of 50 ml / min at the same temperature. After the reduction reaction, weight loss of nickel oxide occurs. Thus, the progress of the reaction can be observed on the basis of weight loss.

The results are shown in FIG.

After reacting for 60 minutes, each test sample was analyzed by electrolytic gravimetry for nickel, atomic absorption photometer for cobalt, copper and sodium and stable gas melt-infrared absorption photometer for oxygen.

Example  1, experimental conditions

Test sample: 80 mg of nickel oxide / 0.002% added NaCO ₃

Treatment temperature .: 900-600 ° C., Reducing gas: Hydrogen, Treatment time: 60 minutes

Comparative example  One

The reduction reaction of nickel oxide was carried out in the same manner as in Example 1 except that NaCO ₃ was not added.

The results are shown in FIG.

After 60 minutes of reaction, each test sample was analyzed in the same manner as in Example 1. As a result, the data shown in Table 1 were obtained.

Comparative example  1, experimental conditions

Test sample: 80 mg of nickel oxide / 0% NaCO ₃ added (not added)

Treatment temperature .: 900-600 ° C., Reducing gas: Hydrogen, Treatment time: 60 minutes

Ni Co Cu Fe O Na Etc Before the reaction 76.61 1.04 0.15 0.50 21.5 <0.001 0.20  Example 1      900 ℃ Reaction 800 ℃ Temperature 700 ℃ 600 ℃ 97.47 1.32 0.18 0.62 0.15 0.002 0.26 97.31 1.33 0.19 0.64 0.33 0.002 0.20 97.10 1.32 0.18 0.64 0.52 0.002 0.24 95.83 1.31 0.19 0.64 1.85 0.002 0.18  Comparative Example 1      900 ℃ Reaction 800 ℃ Temperature 700 ℃ 600 ℃ 93.05 1.26 0.18 0.59 4.67 <0.001 0.25 82.82 1.12 0.16 0.54 15.2 <0.001 0.16 88.63 1.20 0.17 0.58 9.22 <0.001 0.20 92.56 1.26 0.17 0.60 5.24 <0.001 0.17

                                                                (weight%)

Example  2 and Comparative example  2

80 mg of nickel oxide was weighed out. 0.002% by weight of NaCO ₃ was added in the amount of sodium atoms based on the amount of nickel oxide and mixed with nickel oxide. The mixture was charged to a quartz crucible and the crucible was transferred to a TG apparatus that heated the components of the crucible to 900 ° C. Then, the reduction reaction of nickel oxide was performed while supplying hydrogen with reducing gas at a rate of 50 ml / min at the same temperature. After the reduction reaction, weight loss of nickel oxide occurs.

The results are shown in FIG.

Separately, the reduction reaction of nickel oxide was carried out in the same manner as described above, except that NaCO ₃ was not added (Comparative Example 2). The results are shown in FIG.

After reacting for 60 minutes, each test sample was analyzed in the same manner as in Example 1. As a result, the data shown in Table 2 were obtained.

Example  2, experimental conditions

Test sample: 80 mg of nickel oxide / 0.002% added NaCO ₃

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Comparative example  2, experimental conditions

Test sample: 80 mg of nickel oxide / 0% NaCO ₃ added (not added)

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Ni Co Cu Fe O Na Etc Before the reaction 76.61 1.04 0.15 0.50 21.5 <0.001 0.20 Example 2 97.41 1.33 0.19 0.62 0.18 0.002 0.27 Comparative Example 2 88.95 1.21 0.17 0.58 8.89 <0.001 0.20

                                                                (weight%)

Example  3 and Comparative example  3

The reduction reaction of nickel oxide was carried out in the same manner as in Example 2, except that 0.003% by weight of NaOH was added in the amount of sodium atoms based on the amount of nickel oxide instead of NaCO ₃ used in Example 2. .

The results are shown in FIG.

Separately, the reduction reaction of nickel oxide was carried out in the same manner as described above, except that NaOH was not added (Comparative Example 3). The results are shown in FIG.

After reacting for 60 minutes, each test sample was analyzed in the same manner as in Example 2. As a result, the data shown in Table 3 were obtained.

Example  3, experimental conditions

Test sample: 80 mg of nickel oxide / 0.003% added NaOH

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Comparative example  3, experimental conditions

Test sample: 80 mg nickel oxide / 0% NaOH (not added)

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Ni Co Cu Fe O Na Etc Before the reaction 76.61 1.04 0.15 0.50 21.5 <0.001 0.20 Example 3 97.48 1.30 0.18 0.64 0.15 0.003 0.25 Comparative Example 3 88.25 1.20 0.17 0.60 9.57 <0.001 0.21

                                                                (weight%)

Example  4 and Comparative example  4

The reduction reaction of nickel oxide was carried out in the same manner as in Example 2, except that 0.003% by weight of NaCl was added in the amount of sodium atoms based on the amount of nickel oxide instead of NaCO ₃ used in Example 2. .

The results are shown in FIG.

Separately, the reduction reaction of nickel oxide was carried out in the same manner as described above, except that NaCl was not added (Comparative Example 4). The results are shown in FIG.

After reacting for 60 minutes, each test sample was analyzed in the same manner as in Example 2. As a result, the data shown in Table 4 were obtained.

Example  4, experimental conditions

Test sample: 80 mg of nickel oxide / 0.003% added NaCl

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Comparative example  4, experimental conditions

Test Sample: 80 mg of nickel oxide / 0% NaCl added

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Ni Co Cu Fe O Na Etc Before the reaction 76.61 1.04 0.15 0.50 21.5 <0.001 0.20 Example 3 97.51 1.29 0.18 0.64 0.16 0.003 0.22 Comparative Example 3 89.47 1.23 0.19 0.60 8.35 <0.001 0.16

                                                                (weight%)

Example  5 and Comparative example  5

Instead of NaCO ₃ used in Example 2 for the reduction of nickel oxide, sodium silicate containing 0.005% by weight of Na ₂ O, nSiO ₂ and xH ₂ O in an amount of sodium atoms based on the amount of nickel oxide It was carried out in the same manner as in Example 2 except for the addition.

The result was shown in FIG.

Separately, the reduction reaction of nickel oxide was carried out in the same manner as described above, except that sodium silicate was not added (Comparative Example 5). The result was shown in FIG.

After reacting for 60 minutes, each test sample was analyzed in the same manner as in Example 2. As a result, the data shown in Table 5 were obtained.

Example  5, experimental conditions

Test sample: 80 mg nickel oxide / 0.005% added sodium silicate

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Comparative example  5, experimental conditions

Test sample: 80 mg of nickel oxide / 0% added sodium silicate (not added)

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Ni Co Cu Fe O Na Etc Before the reaction 76.61 1.04 0.15 0.50 21.5 <0.001 0.20 Example 5 97.31 1.32 0.19 0.61 0.39 0.004 0.18 Comparative Example 5 89.30 1.18 0.17 0.58 8.54 <0.001 0.23

                                                                (weight%)

Example  6 and Comparative example  6

Example 2 except for the addition of 0.003% by weight of sodium hydrogen sulfite (NaHSO ₃ ) in the amount of sodium atoms based on the amount of nickel oxide, instead of NaCO ₃ used in Example 2 for the reduction reaction of nickel oxide. It was performed in the same manner as.

The result was shown in FIG.

Separately, the reduction reaction of nickel oxide was carried out in the same manner as described above, except that sodium hydrogen sulfite was not added (Comparative Example 6). The results are shown in FIG.

After reacting for 60 minutes, each test sample was analyzed in the same manner as in Example 2. As a result, the data shown in Table 6 were obtained.

Example  6, experimental conditions

Test Sample: 80 mg nickel oxide / 0.003% added sodium hydrogen sulfite

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Comparative example  6, experimental conditions

Test sample: 80 mg of nickel oxide / 0% added sodium hydrogen sulfite (not added)

Treatment temperature: 900 ° C., reducing gas: hydrogen, treatment time: 60 minutes

Ni Co Cu Fe O Na Etc Before the reaction 76.61 1.04 0.15 0.50 21.5 <0.001 0.20 Example 6 97.40 1.31 0.18 0.63 0.19 0.003 0.29 Comparative Example 6 89.43 1.21 0.19 0.58 8.41 <0.001 0.18

                                                                (weight%)

Example  7 and Comparative example  7

This example shows the use of the fluidized bed in the production of nickel metal.

600 g of nickel oxide was weighed out. 0.002% by weight of NaCO ₃ was added to the nickel oxide in an amount of sodium atoms based on the amount of nickel oxide and mixed. This mixture was filled into a stainless steel fluidizing device having a diameter of 60 mm. The fluidization apparatus was heated externally to the desired temperature and nitrogen gas was introduced through the bottom of the apparatus to form a fluidized bed. Reducing gas (propane gas) was added to the fluidized bed to cause a reduction reaction. After a predetermined treatment time, the heating and feeding of the reducing gas was stopped and the reaction system was cooled to room temperature while injecting nitrogen gas. The treated product was sampled and the sample was analyzed in the same manner as in Example 1 to observe the reduction process.

The change in the amount of CO gas and CO ₂ gas in the exhaust gas around the outlet of the fluidized bed is shown in FIG. 8.

Separately, the reduction reaction of nickel oxide was carried out in the same manner as described above, except that NaCO ₃ was not added (Comparative Example 7). The results are shown in FIG.

After 15 minutes of reaction, each test sample was analyzed in the same manner as in Example 1. As a result, the data shown in Table 7 were obtained.

Nickel oxide used in the fluidized bed had the following composition and particle size.

Nickel oxide grade (% by weight)

Ni Co Cu Fe O Etc 76.81 1.06 0.14 0.53 21.40 0.06

Particle size (% by weight) of nickel oxide

More than 820㎛ 820 to 420 μm 420 to 210 μm 210 to 105 µm 105㎛ or less 2 30 60 7 One

Processing conditions

Treatment temperature .: 900 ℃

Processing time: 15 minutes

Reducing gas: propane 0.66 NL / min

Fluid Bed: Nitrogen 1.4 Nm ³ / hour

Ni Co Cu Fe O Na Etc Before the reaction 76.81 1.06 0.14 0.53 21.40 <0.001 0.06 Example 7 97.36 1.33 0.18 0.74 0.18 0.002 0.20 Comparative Example 7 91.69 1.26 0.16 0.63 6.0 <0.001 0.26

                                                               (weight%)

In the context of the present invention

Claims (9)

Performing a catalytic reaction between nickel oxide as a raw material and a reducing gas selected from the group of hydrogen, carbon monoxide, ammonia and methanol to produce nickel metal from nickel oxide, the catalytic reaction comprising sodium carbonate, sodium hydroxide, Sodium-containing compounds selected from the group consisting of sodium chloride, sodium bisulfite, sodium bicarbonate, sodium chlorate, bleaching powder and sodium silicate coexist in an amount of 0.001% to 0.1% by weight of sodium atoms based on the amount of nickel oxide Process for producing nickel metal, which is carried out under. delete delete delete The method of claim 1, The nickel oxide is in the form having a diameter of at most 5mm. The method of claim 1, The contact reaction between the nickel oxide and the reducing gas is carried out at a temperature of 600 to 1000 ℃. delete The nickel content prepared by the method according to any one of claims 1, 5 and 6, wherein the content of sodium in the nickel metal produced by the method is in the amount of sodium atoms based on the amount of the nickel metal. Nickel metal controlled at most 0.0025% by weight. The method of claim 1, The nickel oxide is in the form having a diameter of at most 3mm.

Images