Method for efficient leaching of Joule thermal shock strengthened vanadium titano-magnetite

Abstract

The invention belongs to the technical field of pyrometallurgy and hydrometallurgy, and discloses an efficient leaching method for Joule thermal shock strengthened vanadium titano-magnetite. The Joule thermal shock strengthened vanadium-titanium resource efficient leaching comprises the steps that low-grade vanadium-titanium magnetite ore powder and a carbon source are mixed and then subjected to Joule thermal shock activation treatment, and an obtained activation product is leached through dilute acid or organic acid, so that valuable metal such as vanadium, titanium and iron can be efficiently leached out. Vanadium titano-magnetite and a small amount of carbon powder are subjected to Joule thermal shock, so that the valence state of metal ions is reduced, and the leaching activity of metal is improved. The Joule thermal shock strengthening low-grade vanadium titano-magnetite acid leaching method has the advantages of being high in activation efficiency, high in metal element leaching efficiency and the like.

Description

Technical Field

[0001] The invention relates to a method for efficiently leaching vanadium-titanium magnetite strengthened by Joule thermal shock, and belongs to the technical field of pyrometallurgy and hydrometallurgy. Background Art

[0002] Vanadium-titanium magnetite is a polymetallic mineral resource recognized worldwide as a strategic mineral resource. Vanadium, titanium, iron, and their associated metals play a vital role in the development of human society. my country's vanadium-titanium magnetite resources are widely distributed and abundant, with proven reserves exceeding 30 billion tons, ranking among the highest in the world. Western Liaoning is a newly discovered area with significant vanadium-titanium magnetite reserves, containing vanadium levels far exceeding those found in Panzhihua and Chengde, making it extremely valuable for development and utilization. In recent years, with the rapid economic development of my country, demand for mineral resources such as vanadium, titanium, and iron has been increasing. Therefore, developing the vast reserves of vanadium-titanium magnetite in western Liaoning is of great significance.

[0003] The vanadium-titanium magnetite ore in the Panzhihua region, characterized by high iron grade and low vanadium and titanium grades, is well-suited for blast furnace-converter smelting. However, the vanadium-titanium magnetite ore in western Liaoning exhibits low iron grade and high vanadium and titanium grades, making the concentrate obtained after beneficiation difficult to adapt to the existing blast furnace-converter production process. To efficiently utilize the vanadium-titanium magnetite ore in western Liaoning, researchers have developed pyrometallurgical processes such as direct reduction-electric furnace, direct reduction-magnetic separation, and sodium extraction-pre-reduction-electric furnace. However, for various reasons, these processes have remained elusive and unsuitable for widespread adoption.

[0004] Although wet leaching has also been used to recover valuable metals from vanadium-titanium magnetite in western Liaoning, due to the close coexistence of iron and titanium in vanadium-titanium magnetite, which usually exists in the form of ilmenite, vanadium is often present in magnetite or titanomagnetite in a similar phase. Direct acid leaching often suffers from low leaching efficiency, long leaching time, and incomplete separation of vanadium, titanium, and iron. Due to the high chemical valence of vanadium and titanium in vanadium-titanium magnetite, efficient leaching of vanadium, titanium, and iron usually requires the use of concentrated acid, high temperature, and the presence of a reducing agent. This not only consumes a large amount of leaching chemicals, but also makes the leaching process cumbersome. Therefore, enhancing the efficient leaching of valuable metals from vanadium-titanium magnetite is a key link in the efficient and comprehensive utilization of vanadium-titanium magnetite. Summary of the Invention

[0005] The present invention aims to provide a method for efficient leaching of vanadium-titanium magnetite using Joule thermal shock. The vanadium-titanium magnetite is mixed with a carbon source and then thermally activated in a Joule thermal device. The activated product can be efficiently leached with dilute acid to extract valuable components such as vanadium, titanium, and iron, leaving a silicon-rich slag. The acid leaching process of vanadium-titanium magnetite activated by Joule thermal flash significantly improves the leaching efficiency of valuable metals, shortens the leaching time, and does not require any leaching aids, resulting in low cost and high extraction efficiency.

[0006] A method for efficiently leaching vanadium-titanium magnetite by Joule thermal shock enhancement comprises the following steps:

[0007] Step 1: Mix the vanadium-titanium magnetite powder and the carbon source in proportion and place them in a flash Joule heating device for thermal shock activation treatment;

[0008] Step 2: mixing and stirring the product activated in step 1 with an acid of a certain concentration for leaching;

[0009] Step 3: After leaching, solid-liquid separation is performed to obtain vanadium, titanium, iron leachate and silicon-rich slag respectively.

[0010] In step 1, the particle size of the vanadium-titanium magnetite powder is 90% -200 mesh.

[0011] In step 1, the carbon source used is one of lignite, bituminous coal, coal tar, coke, and biomass carbon.

[0012] In step 1, the mass ratio of vanadium-titanium magnetite powder to carbon source is 20-100:1.

[0013] In step 1, the current applied by the flash Joule heating device is a pulse current, an alternating current, a constant current, a decaying current or a combination of the above currents; the applied current intensity is 40-200A, the current application time is 50-1000ms, and the peak temperature is 1500-3000°C.

[0014] In step 2, the acid used is one of hydrochloric acid, sulfuric acid, citric acid, and acetic acid; and the concentration of the acid is 10%.

[0015] In step 2, the leaching temperature is 30-90° C., the leaching time is 0.5-3 h, and the liquid-to-solid ratio is 1-10 mL / g.

[0016] In step 2, the stirring rate is 100-400 r / min.

[0017] The main chemical reaction equation of the present invention is as follows:

[0018] Fe3O4(s)+C(s)=3FeO(s)+CO2(g)

[0019] FeO(s)+C(s)=Fe(s)+CO2(g)

[0020] FeTiO3(s)+C(s)=FeO(s)+TiO(s)+CO(g)

[0021] V2O5(s)+C(s)=V2O3(s)+CO2(g)

[0022] FeO(s)+2H + (aq)=Fe 2+ (aq)+H2O(l)

[0023] TiO(s)+2H + (aq)=Ti 2+ (aq)+H2O(l)

[0024] V2O3(s)+6H + (aq)=2V 3+ (aq)+3H2O(l)

[0025] The beneficial effects of the present invention are:

[0026] The present invention mixes vanadium-titanium magnetite powder and a carbon source, performs thermal shock activation in a Joule heat device, and the activated product is subjected to dilute acid leaching to extract metal elements such as vanadium, titanium, and iron. During the Joule heat shock activation of the mixture of vanadium-titanium magnetite and a carbon source, the high-valent transition metals in the vanadium-titanium magnetite are rapidly reduced to a low-valent state or a metallic state by carbon, making them more easily leached by acid. In addition, Joule heat shock has the characteristics of rapid heating, high-temperature heat treatment, and rapid quenching. During the high-temperature thermal shock process, a large number of crystal defects are often generated inside the material, which further increases its acid decomposition activity. The present invention significantly improves the leaching efficiency of valuable metals by introducing carbon thermal shock activation, reduces the reaction time, and achieves efficient leaching of vanadium, titanium, and iron.

[0027] The present invention has the characteristics of simple process flow and high recovery rate of valuable metals. It provides a feasible way for the comprehensive and efficient utilization of vanadium-titanium magnetite resources in western Liaoning, my country, and has a very broad prospect for promotion and application. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to specific embodiments.

[0029] Comparative Example 1:

[0030] 1g of vanadium-titanium magnetite powder and 10% hydrochloric acid were mixed and leached at a liquid-to-solid ratio of 10:1. The leaching temperature was 80°C, the leaching time was 60min, and the stirring rate was 300r / min. The leaching efficiencies of vanadium, titanium, and iron were 65.4%, 20.3%, and 70.1%, respectively.

[0031] Comparative Example 2:

[0032] 1 g of vanadium-titanium magnetite ore powder and 10% concentration of citric acid were mixed and leached at a liquid-solid ratio of 10:1, the leaching temperature was 80°C, the leaching time was 60 min, and the stirring rate was 400 r / min. The leaching efficiencies of vanadium, titanium, and iron were 24.3%, 2.9%, and 39.4%, respectively.

[0033] Comparative Example 3:

[0034] 1 g of vanadium-titanium magnetite ore powder was subjected to thermal shock activation in a joule heat device, the applied current time was 500 ms, the peak temperature was 2500°C, and the activated product was mixed and leached with 10% concentration of sulfuric acid at a liquid-solid ratio of 15:1, the leaching temperature was 50°C, the leaching time was 90 min, and the stirring rate was 400 r / min. The leaching efficiencies of vanadium, titanium, and iron were 82.1%, 45.3%, and 88.6%, respectively.

[0035] Example 1:

[0036] 1 g of vanadium-titanium magnetite ore powder and 0.05 g of lignite were mixed and subjected to carbon thermal shock in a joule heat device, the applied current intensity was 170 A, the applied current time was 500 ms, the peak temperature was 2200°C, and the activated product was mixed and leached with 10% concentration of sulfuric acid at a liquid-solid ratio of 8:1, the leaching temperature was 80°C, the leaching time was 60 min, and the stirring rate was 400 r / min. The leaching efficiencies of vanadium, titanium, and iron were 97.3%, 95.1%, and 98.7%, respectively.

[0037] Example 2:

[0038] 1 g of vanadium-titanium magnetite ore powder and 0.05 g of lignite were mixed and subjected to carbon thermal shock in a joule heat device, the applied current intensity was 150 A, the applied current time was 100 ms, the peak temperature was 2000°C, and the activated product was mixed and leached with 10% concentration of sulfuric acid at a liquid-solid ratio of 8:1, the leaching temperature was 80°C, the leaching time was 60 min, and the stirring rate was 400 r / min. The leaching efficiencies of vanadium, titanium, and iron were 81.3%, 78.4%, and 86.7%, respectively.

[0039] Example 3:

[0040] 1g of vanadium-titanium magnetite powder and 0.05g of lignite were mixed and subjected to carbon thermal shock in a Joule heat device. The applied current intensity was 180A, the applied current time was 600ms, and the peak temperature was 2300℃. The activated product was mixed with 10% sulfuric acid at a liquid-solid ratio of 5:1 for leaching. The leaching temperature was 30℃, the leaching time was 90min, and the stirring rate was 400r / min. The leaching efficiencies of vanadium, titanium, and iron were 82.1%, 71.6%, and 88.4%, respectively.

[0041] Example 4:

[0042] 1g of vanadium-titanium magnetite powder and 0.1g of coke were mixed and subjected to carbon thermal shock in a Joule heat device. The applied current intensity was 200A, the applied current time was 500ms, and the peak temperature was 2500℃. The activated product was mixed with 10% hydrochloric acid at a liquid-solid ratio of 10:1 for leaching. The leaching temperature was 80℃, the leaching time was 60min, and the stirring rate was 400r / min. The leaching efficiencies of vanadium, titanium, and iron were 95.3%, 93.2%, and 96.6%, respectively.

[0043] Example 5:

[0044] 1g of vanadium-titanium magnetite powder and 0.1g of anthracite were mixed and subjected to carbon thermal shock in a Joule heat device. The applied current intensity was 180A, the applied current time was 500ms, and the peak temperature was 2300℃. The activated product was mixed with 10% citric acid at a liquid-solid ratio of 10:1 for leaching. The leaching temperature was 80℃, the leaching time was 120min, and the stirring rate was 400r / min. The leaching efficiencies of vanadium, titanium, and iron were 91.4%, 88.2%, and 93.6%, respectively.

[0045] Example 6:

[0046] 1g of vanadium-titanium magnetite powder and 0.1g of coal tar were mixed and subjected to carbon thermal shock in a Joule heat device. The applied current intensity was 180A, the applied current time was 600ms, and the peak temperature was 2300℃. The activated product was mixed with 10% acetic acid at a liquid-solid ratio of 10:1 for leaching. The leaching temperature was 80℃, the leaching time was 90min, and the stirring rate was 400r / min. The leaching efficiencies of vanadium, titanium, and iron were 92.3%, 91.3%, and 95.8%, respectively.

[0047] Example 7:

[0048] 1g of vanadium-titanium magnetite powder and 0.1g of biochar were mixed and subjected to carbon thermal shock in a Joule heat device. The applied current intensity was 200A, the applied current time was 500ms, and the peak temperature was 2500℃. The activated product was mixed with 10% acetic acid at a liquid-solid ratio of 10:1 for leaching. The leaching temperature was 50℃, the leaching time was 60min, and the stirring rate was 400r / min. The leaching efficiencies of vanadium, titanium, and iron were 83.4%, 77.6%, and 88.9%, respectively.

Claims

1. A method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement, characterized in that: The following steps are involved: Step 1: Mix the vanadium-titanium magnetite powder and the carbon source in proportion and place them in a flash Joule heating device for thermal shock activation treatment; Step 2: mixing and stirring the product activated in step 1 with an acid of a certain concentration for leaching; Step 3: After leaching, solid-liquid separation is performed to obtain vanadium, titanium, iron leachate and silicon-rich slag respectively.

2. The method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement according to claim 1, characterized in that: In step 1, the particle size of the vanadium-titanium magnetite powder is 90% -200 mesh.

3. The method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement according to claim 1, characterized in that: In step 1, the carbon source used is one of lignite, bituminous coal, coal tar, coke, and biomass carbon.

4. The method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement according to claim 1, characterized in that: In step 1, the mass ratio of vanadium-titanium magnetite powder to carbon source is 20-100:

1.

5. The method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement according to claim 1, characterized in that: In step 1, the current applied by the flash Joule heating device is a pulse current, an alternating current, a constant current, a decaying current or a combination of the above currents; the applied current intensity is 40-200A, the current application time is 50-1000ms, and the peak temperature is 1500-3000°C.

6. The method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement according to claim 1, characterized in that: In step 2, the acid used is one of hydrochloric acid, sulfuric acid, citric acid, and acetic acid; and the concentration of the acid is 10%.

7. The method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement according to claim 1, characterized in that: In step 2, the leaching temperature is 30-90° C., the leaching time is 0.5-3 h, and the liquid-to-solid ratio is 1-10 mL / g.

8. The method for efficient leaching of vanadium-titanium magnetite by Joule thermal shock enhancement according to claim 1, characterized in that: In step 2, the stirring rate is 100-400 r / min.