SINTERING-RESISTANT MATERIAL, AND PREPARATION METHOD AND USE THEREOF

Abstract

The present disclosure discloses a sintering-resistant material, and a preparation method and use thereof. The sintering-resistant material includes magnesium oxide, an anti-corrosive agent, an antioxidant, and a binder, where the anti-corrosive agent includes a barite powder and a porous graphite powder; the antioxidant includes aluminum carbide and an aluminum powder; the binder includes a metal chloride and a silica sol; and metals in the raw materials are all extracted from a hydrochloric acid leachate of an electric furnace slag. In the present disclosure, the preparation method of the present disclosure improves the resource utilization of the electric furnace slag. Magnesium and aluminum have the largest proportion among metal elements in the electric furnace slag, and thus magnesium oxide is used as the main material. In addition, other chloride salts leached out from the electric furnace slag by hydrochloric acid can be directly or indirectly used.

Claims

1. A sintering-resistant material, comprising the following raw materials: magnesium oxide, an anti-corrosive agent, an antioxidant, and a binder, wherein the anti-corrosive agent comprises a barite powder and a porous graphite powder; the antioxidant comprises aluminum carbide and an aluminum powder; and the binder comprises a metal chloride and a silica sol.

2. The sintering-resistant material according to claim 1, wherein the magnesium oxide, the anti-corrosive agent, the antioxidant, and the binder are at a mass ratio of (80-150):(1-15):(1-10):(0.1-10).

3. The sintering-resistant material according to claim 1, wherein a mass ratio of the barite powder to the porous graphite powder is (80-150):(1-10).

4. The sintering-resistant material according to claim 1, wherein a mass ratio of the aluminum carbide to the aluminum powder is (20-100):(1-30).

5. The sintering-resistant material according to claim 1, wherein a mass ratio of the metal chloride to the silica sol is 10:(1-5); and preferably, the metal chloride is one or more selected from the group consisting of iron chloride, chromium chloride, zinc chloride, cobalt chloride, and nickel chloride.

6. A preparation method of the sintering-resistant material according to claim 1, wherein metals in the raw materials are all extracted from an electric furnace slag, and the preparation method specifically comprises the following steps: mixing an electric furnace slag powder with hydrochloric acid for acid leaching, and conducting solid-liquid separation to obtain a leachate; evaporating hydrogen chloride from the leachate to obtain a chloride salt solution, adjusting the pH of the chloride salt solution with an alkali liquor to precipitate aluminum hydroxide and magnesium hydroxide separately, and evaporating a resulting chloride salt solution after the precipitation to obtain a chloride salt crystal; subjecting the magnesium hydroxide to dehydration at a high temperature to obtain the magnesium oxide; subjecting the chloride salt crystal to dehydration at a high temperature to obtain a metal chloride; and subjecting the aluminum hydroxide to a reaction with a reducing agent to obtain aluminum, and mixing the aluminum with powdered carbon to allow a reaction to obtain the antioxidant; mixing the barite powder and the porous graphite powder to obtain the anti-corrosive agent, and mixing the metal chloride with the silica sol to obtain the binder; and mixing the magnesium oxide, the anti-corrosive agent, the antioxidant, and the binder in proportion to obtain a mixture, pressing the mixture into a blank, and heating the blank in an inert atmosphere to obtain the sintering-resistant material.

7. The preparation method according to claim 6, wherein a solid-to-liquid ratio of the electric furnace slag powder to the hydrochloric acid is 10:(40-80) (g/mL); and preferably, the hydrochloric acid has a concentration of 8 mol/L to 12 mol/L.

8. The preparation method according to claim 6, wherein the aluminum hydroxide is precipitated out at a pH of 3.0 to 4.8; and the magnesium hydroxide is precipitated out at a pH of 9.0 to 10.5.

9. The preparation method according to claim 6, wherein the reducing agent is one or more selected from the group consisting of powdered carbon, pulverized coal, carbon monoxide, hydrogen, and hydrogen sulfide; and preferably, the reaction of the aluminum hydroxide with the reducing agent is conducted at 600° C. to 1,100° C.

10. Use of the sintering-resistant material according to claim 1 in the recycling of a scrapped power battery.

11. Use of the sintering-resistant material according to claim 2 in the recycling of a scrapped power battery.

12. Use of the sintering-resistant material according to claim 3 in the recycling of a scrapped power battery.

13. Use of the sintering-resistant material according to claim 4 in the recycling of a scrapped power battery.

14. Use of the sintering-resistant material according to claim 5 in the recycling of a scrapped power battery.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present disclosure is further described below with reference to accompanying drawings and examples.

[0036] FIG. 1 is a process flow diagram of Example 1 of the present disclosure; and

[0037] FIG. 2 is a scanning electron microscopy (SEM) image of the electric furnace slag in Example 1 of the present disclosure;

[0038] FIG. 3 is an SEM image of the sintering-resistant material of Example 1 of the present disclosure; and

[0039] FIG. 4 is an SEM image of the sintering-resistant material of Comparative Example 1 of the present disclosure.

DETAILED DESCRIPTION OF ILLUSTRATED EXAMPLES

[0040] The concepts and technical effects of the present disclosure are clearly and completely described below in conjunction with examples, so as to allow the objectives, features and effects of the present disclosure to be fully understood. Apparently, the described examples are merely some rather than all of the examples of the present disclosure. All other examples obtained by those skilled in the art based on the examples of the present disclosure without creative efforts should fall within the protection scope of the present disclosure.

Example 1

[0041] In this example, a sintering-resistant material was prepared. The sintering-resistant material was composed of magnesium oxide, an anti-corrosive agent, an antioxidant, and a binder in a mass ratio of 110:4.5:2.0:2.5. The anti-corrosive agent was composed of a barite powder and a porous graphite powder in a mass ratio of 110:7.5; the antioxidant was composed of aluminum carbide and an aluminum powder in a mass ratio of 35:3.7; and the binder was composed of a metal chloride and a silica sol in a mass ratio of 10:1.2, and the metal chloride included iron chloride, chromium chloride, zinc chloride, cobalt chloride, and nickel chloride. As shown in FIG. 1, a specific preparation process was as follows: [0042] (1) Leaching of an electric furnace slag powder: The electric furnace slag powder was mixed with 9.3 mol/L hydrochloric acid in a solid-to-liquid ratio of 10:55 (g/mL), and a resulting electric furnace slag slurry was stirred to allow a reaction for 36 min to obtain an acid-leaching slurry; and the acid-leaching slurry was cooled, washed twice with hot water at about 63° C. (where a volume ratio of the acid-leaching slurry to the hot water was 100:850 each time), and then subjected to suction filtration to obtain a leachate and an insoluble residue, where the insoluble residue was a silicon residue (silicon dioxide) and salts in the leachate were magnesium chloride, iron chloride, aluminum chloride, chromium chloride, zinc chloride, cobalt chloride, and nickel chloride. [0043] (2) Recovery of hydrolysates from the leachate: The leachate was delivered to an evaporation device, and hydrogen chloride was evaporated at about 90° C. until a volume of the leachate was reduced by about 280 ml/L to obtain a chloride salt solution; by adding a sodium hydroxide solution with a concentration of 0.15 mol/L, a pH of the chloride salt solution was first adjusted to 3.62 to recover an aluminum hydroxide precipitate and then adjusted to 9.57 to recover a magnesium hydroxide precipitate; and a resulting chloride salt solution was subjected to evaporation to obtain a chloride salt crystal. [0044] (3) Preparation of the composite antioxidant, the magnesium oxide, and the metal chloride: The magnesium hydroxide and the chloride salt crystal were separately subjected to dehydration at 245° C. for 32 min in a kiln to obtain anhydrous magnesium oxide and a metal chloride; and the aluminum hydroxide was reduced by powdered carbon at about 1,020° C. in a kiln to obtain aluminum, the aluminum was ball-milled into an aluminum powder and then mixed with an appropriate amount of powdered carbon, and a resulting mixture was subjected to a reaction for 240 min at about 860° C. in an argon atmosphere in a furnace to obtain the aluminum carbide-aluminum powder composite antioxidant, where a mass ratio of the aluminum carbide to the aluminum powder was 3:1. [0045] (4) Preparation of the anti-corrosive agent and the binder: The barite powder and the porous graphite powder were mixed in a drying mixer at a mass ratio of 110:7.5 to obtain the anti-corrosive agent, and the metal chloride and the silica sol were mixed at a mass ratio of 10:1.2 to obtain the binder. [0046] (5) Preparation of the sintering-resistant material: The anhydrous magnesium oxide, the anti-corrosive agent, the antioxidant, and the binder were mixed in a mixer at a mass ratio of 110:4.5:2.0:2.5 to obtain a mixture, where the materials were mixed specifically as follows: the magnesium oxide and the anti-corrosive agent were thoroughly mixed, then the antioxidant and the binder were added, and a resulting mixture was thoroughly mixed; the mixture was pressed into a blank in a pressing machine; and in a nitrogen atmosphere, the blank was heated to about 1,380° C. and kept at the temperature for 180 min in an electric induction furnace to obtain the sintering-resistant material. Referring to FIG. 2 and FIG. 3, they are a scanning electron microscopy (SEM) image of the electric furnace slag and an SEM image of the sintering-resistant material of Example 1 respectively.

Example 2

[0047] In this example, a sintering-resistant material was prepared. The sintering-resistant material was composed of magnesium oxide, an anti-corrosive agent, an antioxidant, and a binder in a mass ratio of 100:3.5:2.5:1.0. The anti-corrosive agent was composed of a barite powder and a porous graphite powder in a mass ratio of 100:7.5; the antioxidant was composed of aluminum carbide and an aluminum powder in a mass ratio of 33:6.1; and the binder was composed of a metal chloride and a silica sol in a mass ratio of 10:1.5, and the metal chloride included iron chloride, chromium chloride, zinc chloride, cobalt chloride, and nickel chloride. A specific preparation process was as follows: [0048] (1) Leaching of an electric furnace slag powder: The electric furnace slag powder was mixed with 9.5 mol/L hydrochloric acid in a solid-to-liquid ratio of 10:55 (g/mL), and a resulting electric furnace slag slurry was stirred to allow a reaction for 40 min to obtain an acid-leaching slurry; and the acid-leaching slurry was cooled, washed twice with hot water at about 75° C. (where a volume ratio of the acid-leaching slurry to the hot water was 100:860 each time), and then subjected to suction filtration to obtain a leachate and an insoluble residue, where the insoluble residue was a silicon residue (silicon dioxide) and salts in the leachate were magnesium chloride, iron chloride, aluminum chloride, chromium chloride, zinc chloride, cobalt chloride, and nickel chloride. [0049] (2) Recovery of hydrolysates from the leachate: The leachate was delivered to an evaporation device, and hydrogen chloride was evaporated at about 82° C. until a volume of the leachate was reduced by about 340 ml/L to obtain a chloride salt solution; by adding a sodium hydroxide solution with a concentration of 0.50 mol/L, a pH of the chloride salt solution was first adjusted to 3.87 to recover an aluminum hydroxide precipitate and then adjusted to 9.68 to recover a magnesium hydroxide precipitate; and a resulting chloride salt solution was subjected to evaporation to obtain a chloride salt crystal. [0050] (3) Preparation of the composite antioxidant, the magnesium oxide, and the metal chloride: The magnesium hydroxide and the chloride salt crystal were separately subjected to dehydration at 270° C. for 36 min in a drying oven to obtain anhydrous magnesium oxide and a metal chloride; and the aluminum hydroxide was reduced by pulverized coal at about 1,020° C. in a kiln to obtain aluminum, the aluminum was ball-milled into an aluminum powder and then mixed with an appropriate amount of powdered carbon, and a resulting mixture was subjected to a reaction for 300 min at about 980° C. in an argon atmosphere in a furnace to obtain the aluminum carbide-aluminum powder composite antioxidant, where a mass ratio of the aluminum carbide to the aluminum powder was 7:2. [0051] (4) Preparation of the anti-corrosive agent and the binder: The barite powder and the porous graphite powder were mixed in a drying mixer at a mass ratio of 100:7.5 to obtain the anti-corrosive agent, and the metal chloride and the silica sol were mixed at a mass ratio of 10:1.5 to obtain the binder. [0052] (5) Preparation of the sintering-resistant material: The anhydrous magnesium oxide, the anti-corrosive agent, the antioxidant, and the binder were mixed in a mixer at a mass ratio of 100:3.5:2.5:1.0 to obtain a mixture, where the materials were mixed specifically as follows: the magnesium oxide and the anti-corrosive agent were thoroughly mixed, then the antioxidant and the binder were added, and a resulting mixture was thoroughly mixed; the mixture was pressed into a blank in a pressing machine; and in a nitrogen atmosphere, the blank was heated to about 1,450° C. and kept at the temperature for 200 min in an electric induction furnace to obtain the sintering-resistant material.

Example 3

[0053] In this example, a sintering-resistant material was prepared. The sintering-resistant material was composed of magnesium oxide, an anti-corrosive agent, an antioxidant, and a binder in a mass ratio of 120:5.5:2.5:3.5. The anti-corrosive agent was composed of a barite powder and a porous graphite powder in a mass ratio of 120:7.5; the antioxidant was composed of aluminum carbide and an aluminum powder in a mass ratio of 48:14.5; and the binder was composed of a metal chloride and a silica sol in a mass ratio of 10:1.8, and the metal chloride included iron chloride, chromium chloride, zinc chloride, cobalt chloride, and nickel chloride. A specific preparation process was as follows: [0054] (1) Leaching of an electric furnace slag powder: The electric furnace slag powder was mixed with 9.3 mol/L hydrochloric acid in a solid-to-liquid ratio of 10:70 (g/mL), and a resulting electric furnace slag slurry was stirred to allow a reaction for 35 min to obtain an acid-leaching slurry; and the acid-leaching slurry was cooled, washed twice with hot water at about 88° C. (where a volume ratio of the acid-leaching slurry to the hot water was 100:920 each time), and then subjected to suction filtration to obtain a leachate and an insoluble residue, where the insoluble residue was a silicon residue (silicon dioxide) and salts in the leachate were magnesium chloride, iron chloride, aluminum chloride, chromium chloride, zinc chloride, cobalt chloride, and nickel chloride. [0055] (2) Recovery of hydrolysates from the leachate: The leachate was delivered to an evaporation device, and hydrogen chloride was evaporated at about 95° C. until a volume of the leachate was reduced by about 330 ml/L to obtain a chloride salt solution; by adding a sodium hydroxide solution with a concentration of 0.30 mol/L, a pH of the chloride salt solution was first adjusted to 3.83 to recover an aluminum hydroxide precipitate and then adjusted to 9.74 to recover a magnesium hydroxide precipitate; and a resulting chloride salt solution was subjected to evaporation to obtain a chloride salt crystal. [0056] (3) Preparation of the composite antioxidant, the magnesium oxide, and the metal chloride: The magnesium hydroxide and the chloride salt crystal were separately subjected to dehydration at 285° C. for 36 min in a drying oven to obtain anhydrous magnesium oxide and a metal chloride; and the aluminum hydroxide was reduced by pulverized coal at about 1,050° C. in a kiln to obtain aluminum, the aluminum was ball-milled into an aluminum powder and then mixed with an appropriate amount of powdered carbon, and a resulting mixture was subjected to a reaction for 360 min at about 1,345° C. in an argon atmosphere in a furnace to obtain the aluminum carbide-aluminum powder composite antioxidant, where a mass ratio of the aluminum carbide to the aluminum powder was 5:1. [0057] (4) Preparation of the anti-corrosive agent and the binder: The barite powder and the porous graphite powder were mixed in a drying mixer at a mass ratio of 120:7.5 to obtain the anti-corrosive agent, and the metal chloride and the silica sol were mixed at a mass ratio of 10:1.8 to obtain the binder. [0058] (5) Preparation of the sintering-resistant material: The anhydrous magnesium oxide, the anti-corrosive agent, the antioxidant, and the binder were mixed in a mixer at a mass ratio of 120:5.5:2.5:3.5 to obtain a mixture, where the materials were mixed specifically as follows: the magnesium oxide and the anti-corrosive agent were thoroughly mixed, then the antioxidant and the binder were added, and a resulting mixture was thoroughly mixed; the mixture was pressed into a blank in a pressing machine; and in a nitrogen atmosphere, the blank was heated to about 1,360° C. and kept at the temperature for 250 min in an electric induction furnace to obtain the sintering-resistant material.

Comparative Example 1

[0059] In this comparative example, a sintering-resistant material was prepared. In a preparation process of this comparative example, the silicon residue in step (1) was used instead of the magnesium oxide to prepare the sintering-resistant material; the steps (1) to (4) were the same as in Example 1; and the step (5) was specifically as follows: [0060] preparation of the sintering-resistant material: the silicon residue, the anti-corrosive agent, the antioxidant, and the binder were mixed in a mixer at a mass ratio of 110:4.5:2.0:2.5 to obtain a mixture, where the materials were mixed specifically as follows: the silicon residue and the anti-corrosive agent were thoroughly mixed, then the antioxidant and the binder were added, and a resulting mixture was thoroughly mixed; the mixture was pressed into a blank in a pressing machine; and in a nitrogen atmosphere, the blank was heated to about 1,380° C. and kept at the temperature for 180 min in an electric induction furnace to obtain the sintering-resistant material. Referring to FIG. 4, it is an SEM image of the sintering-resistant material of Comparative Example 1.

Comparative Example 2

[0061] In this comparative example, a sintering-resistant material was prepared. In a preparation process of this comparative example, the silicon residue in step (1) was used instead of 85 parts among the 110 parts of magnesium oxide to prepare the sintering-resistant material; the steps (1) to (4) were the same as in Example 1; and the step (5) was specifically as follows: [0062] preparation of the sintering-resistant material: the silicon residue, the anhydrous magnesium oxide, the anti-corrosive agent, the antioxidant, and the binder were mixed in a mixer at a mass ratio of 85:35:4.5:2.0:2.5 to obtain a mixture, where the materials were mixed specifically as follows: the silicon residue, the magnesium oxide, and the anti-corrosive agent were thoroughly mixed, then the antioxidant and the binder were added, and a resulting mixture was thoroughly mixed; the mixture was pressed into a blank in a pressing machine; and in a nitrogen atmosphere, the blank was heated to about 1,380° C. and kept at the temperature for 180 min in an electric induction furnace to obtain the sintering-resistant material.

Comparative Example 3

[0063] In this comparative example, a sintering-resistant material was prepared. In a preparation process of this comparative example, no antioxidant was added into the sintering-resistant material; the steps (1) to (4) were the same as in Example 1; and the step (5) was specifically as follows: [0064] preparation of the sintering-resistant material: the anhydrous magnesium oxide, the anti-corrosive agent, and the binder were mixed in a mixer at a mass ratio of 100:3.5:1.0 to obtain a mixture, where the materials were mixed specifically as follows: the magnesium oxide and the anti-corrosive agent were thoroughly mixed, then the binder was added, and a resulting mixture was thoroughly mixed; the mixture was pressed into a blank in a pressing machine; and in a nitrogen atmosphere, the blank was heated to about 1,460° C. and kept at the temperature for 180 min in an electric induction furnace to obtain the sintering-resistant material.

[0065] The sintering-resistant materials prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to a sintering-resistance test in a rotary kiln. During the test, 14 batches of electrode materials were roasted at 400° C. to 900° C.

TABLE-US-00001 TABLE 1 Performance test of the sintering-resistant materials obtained in the examples and comparative examples Reduction/ Falling-off (%) Compressive thickness/mm Mass strength/ Thickness difference MPa Test item Density (g/cm.sup.3) difference before Pressing Detection Mass-to-volume before and after and after machine method ratio sintering sintering test Example 1 3.11 0.3-1.8 0.14 38.64 Example 2 3.14 0.1-1.9 0.16 38.47 Example 3 3.15 0.8-1.4 0.11 38.71 Comparative 2.87 1.2-5.1 0.34 34.89 Example 1 Comparative 2.92 1.7-4.0 0.30 36.48 Example 2 Comparative 3.23 2.3-6.5 0.54 38.35 Example 3

[0066] It can be seen from Table 1 that Comparative Examples 1 and 2 have a lower compressive strength than the examples, and this is because Comparative Examples 1 and 2 include a large amount of silicon-based oxides, which reduces the compressive strength of the sintering-resistant material. A sintering reduction in Comparative Example 3 is significantly higher than that in the examples, resulting in a larger falling-off thickness, and this is because no antioxidant is added in Comparative Example 3, which makes the material more prone to oxidation, makes a structure of the material more likely to become brittle, and more of the material fall off after repeated roasting. In addition, Comparative Example 1 has a larger falling-off thickness and a greater reduction than Comparative Example 2, which indicates that the addition of a specified proportion of anhydrous magnesium oxide in the silicon residue as the main material can also improve the corrosion resistance and oxidation resistance to some extent.

[0067] The examples of present disclosure are described in detail with reference to the accompanying drawings, but the present disclosure is not limited to the above examples. Within the scope of knowledge possessed by those of ordinary skill in the technical field, various changes can also be made without departing from the purpose of the present disclosure. In addition, the examples in the present disclosure or features in the examples may be combined with each other in a non-conflicting situation.