Method for extracting lithium from lithium chlorite ore
Through low temperature sulfuric acid roasting and optimized water-implantation conditions, the problem of low lithium leaching rate in lithium chlorite ore is solved, and efficient lithium extraction and simplified separation and purification process is achieved.
Patent Information
- Application Number
- CN202411796006.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-21
- Publication Date
- 2025-08-15
AI Technical Summary
The prior art is difficult to effectively dissociate lithium minerals in lithium chlorite, resulting in a low lithium leaching rate and conventional calcining additives introduce impurity ions, affecting subsequent separation and purification.
Use sulfuric acid as a baking agent to roast lithium chlorite ore under low-temperature roasting conditions, and then water-soaked at a solid-liquid ratio of 1:4. The baking temperature is controlled to be 400℃, the time is 1 hour, the oscillation frequency is 150r/min, the leaching temperature is 80℃, and the leaching time is 1 hour, ensuring efficient extraction of lithium.
The lithium leachate rate is achieved above 96%, avoiding the introduction of impurity ions, and simplifying the subsequent separation and purification process.
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Abstract
Description
Technical Field
[0001] The present invention relates to the field of mineral technology, and in particular to a method for extracting lithium from lithium chlorite ore. Background Art
[0002] The lithium mineralization in the mining area is clay-based, with chlorite being the primary carrier mineral for Li₂O. This new mineral type is primarily composed of quartz, kaolinite, calcite, and chalcite, with minor amounts of pyrite and dickite. Lithium occurs as chalcite and kaolinite, forming small, scaly flakes unevenly distributed among the quartz grains. The particle size distribution of the chalcite and kaolinite minerals ranges from -5μm (74%) to 25μm to 10μm (26%). Multi-element mass analysis of the raw ore is shown in Table 1. The primary chemical components are CaO, Al₂O₃, Fe₂O₃, MgO, and K₂O, followed by TiO₂, Li₂O, Na₂O, MnO₂, and P₂O₅. The Li₂O content is 0.57%.
[0003] Table 1 Chemical composition analysis results of raw ore
[0004] element / % <![CDATA[Li2O]]> <![CDATA[K2O]]> <![CDATA[Na2O]]> <![CDATA[MnO2]]> <![CDATA[TiO2]]> content 0.57 0.82 0.03 0.02 0.27 element / % <![CDATA[Al2O3]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[P2O5]]> content 17.42 9.97 0.36 0.23 0.36
[0005] Because the useful mineral lithium chlorite and the gangue mineral quartz particles are embedded in a fine particle size, conventional grinding equipment is difficult to dissociate the mineral well. Even when the lithium mineral is ground to the floatable particle size and dissociated, the ore has been severely muddied, which is not conducive to flotation. Summary of the Invention
[0006] In view of the above problems, the present invention provides a method for extracting lithium from lithium chlorite ore, which can improve the lithium leaching rate in the lithium chlorite ore.
[0007] A method for extracting lithium from lithium chlorite ore, comprising the following steps:
[0008] 1) After the raw ore is crushed, ground, filtered and dried, the ore body particle size is -0.038mm, accounting for 78%-93.65%;
[0009] 2) Sulfuric acid is mixed with the ore body at a rate of 0.8-2.4 kg / t and roasted at a temperature of 210-500° C. for 0.5-5 h;
[0010] 3) The calcined reactants are crushed and then mixed with water at a solid-liquid mass ratio of 1:2-1:4, with a constant temperature oscillator at an oscillation frequency of 0-150 r / min, a leaching temperature of 60-90° C., and a leaching time of 0.5-2.5 h;
[0011] In step 1), the ore body particle size is -0.038 mm, accounting for 88.76%
[0012] The calcination temperature in step 2) is 400°C.
[0013] The calcination time in step 2) is 1 hour.
[0014] In the step 2), the amount of sulfuric acid used as the roasting agent is mixed with the ore body at 0.8 kg / t.
[0015] The leaching temperature in step 3) is 80°C.
[0016] The leaching time in step 3) is 1 hour.
[0017] In step 3), the constant temperature oscillator has an oscillation frequency of 150 r / min.
[0018] The calcined reactants in step 3) are crushed and then mixed with water at a solid-liquid mass ratio of 1:4.
[0019] The present invention uses sulfuric acid as a roasting aid, which not only reduces the roasting temperature but also shortens the roasting time. The reactant is mainly lithium sulfate, and no other impurity ions are introduced, which is conducive to subsequent separation and purification. The method can extract lithium with a lithium leaching rate of up to 96%, which is ideal compared with other roasting aids.
[0020] A single alkaline additive (such as carbonate) was mixed with this type of ore sample, roasted at 1000°C for 4 hours, and then water-leached. About 10% of the lithium volatilized during the roasting process, and the lithium leaching rate was less than 45%.
[0021] The sample was mixed with a multi-alkaline additive (potassium chloride-calcium sulfate) and roasted at 800°C for 4 hours before leaching. The lithium leaching rate was about 67%, which was relatively good. However, the use of potassium salt as an additive will cause a large amount of potassium to enter the leachate, and the introduction of impurity ions will bring difficulties to subsequent separation and purification.
[0022] Using calcium oxide, calcium fluoride and sodium chloride as roasting aids, after mixed roasting at 1000℃ for 2h, the lithium leaching rate is about 86% after leaching with 50% sulfuric acid at 20℃ for 1h. However, calcium fluoride as a roasting aid can produce hydrofluoric acid in the subsequent acid leaching process, which is not only extremely corrosive but also causes other side reactions, resulting in the simultaneous leaching of other impurity ions, affecting subsequent separation and purification.
[0023] The above method not only has a high roasting temperature and a long roasting time, but also has a relatively poor lithium leaching rate and effect. In addition, the introduction of impurity ions is not conducive to subsequent separation and extraction, resulting in an overall unsatisfactory effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 : Trend diagram of the effect of roasting temperature on leaching rate;
[0025] Figure 2 : Trend diagram of the effect of roasting particle size on leaching rate;
[0026] Figure 3 : Trend diagram of the effect of roasting time on leaching rate;
[0027] Figure 4 : The trend diagram of the effect of roasting agent dosage on leaching rate;
[0028] Figure 5 : Trend diagram of the influence of leaching temperature on leaching rate;
[0029] Figure 6 : Trend diagram of the effect of leaching time on leaching rate;
[0030] Figure 7 :The trend diagram of the influence of oscillation frequency on leaching rate;
[0031] Figure 8 : Trend diagram of the influence of leaching solid-liquid ratio on leaching rate. DETAILED DESCRIPTION
[0032] Example 1
[0033] A method for extracting lithium from lithium chlorite ore, comprising the following steps:
[0034] 1) After the raw ore is crushed, ground, filtered and dried, the ore body particle size is -0.038mm, accounting for more than 89%;
[0035] 2) Sulfuric acid is mixed with the ore body in a mass ratio of 0.8:1 and roasted at 400°C for 1 hour;
[0036] 3) The calcined reactants were crushed and then mixed in water at a solid-liquid mass ratio of 1:4, with a constant temperature oscillator at an oscillation frequency of 150 r / min, a leaching temperature of 80°C, and a leaching time of 1 h;
[0037] 1. Calcination temperature condition test
[0038] The initial test conditions were 10g and 20g of ore samples, roasting time 2h, roasting particle size -400 mesh accounting for 78%, roasting agent concentrated sulfuric acid dosage 1.1kg / t, leaching temperature 80℃, leaching time 1h, oscillation frequency 150r / min, leaching solid-liquid ratio 1:3, to explore the effect of roasting temperature on leaching rate. The data are shown in Table 3.
[0039] Table 3 Calcination temperature test results
[0040]
[0041]
[0042] When the ore sample is leached at room temperature (25°C), the Li2O leaching rate is only 10.69%; when the roasting temperature is increased to 400°C, the Li2O leaching rate can reach a maximum of 94.48%; when the roasting temperature is 800°C, the Li2O leaching rate decreases to 22.68%. As the roasting temperature increases, the Li2O leaching rate increases first and then decreases. The temperature has a great influence on the leaching rate. Figure 1 When the roasted ore samples were 10g and 20g respectively, the leaching rates of the two groups of parallel samples were slightly different. The Li2O leaching rate of the 20g roasted ore sample was slightly lower, which may be due to incomplete roasting or incomplete washing after leaching. Therefore, only 10g ore samples were used for roasting in subsequent experiments, and the optimal roasting temperature was 400℃.
[0043] 2. Roasting particle size condition test
[0044] The experimental conditions are 10g of ore sample, roasting temperature 400℃, roasting time 2h, roasting agent concentrated sulfuric acid dosage 1.1kg / t, leaching temperature 80℃, leaching time 1h, oscillation frequency 150r / min, leaching solid-liquid ratio 1:3, to explore the effect of roasted ore sample particle size on the leaching rate. The experimental data are shown in Table 4.
[0045] Table 4 Calcination particle size test results
[0046]
[0047]
[0048] When the particle size of -0.038mm accounts for 40.92%, 59.75%, 72.66%, 76%, 78%, 79.89%, 88.86% and 93.65% respectively, the Li2O leaching rate fluctuates between 87.58% and 95.15%, showing an overall upward trend. When the particle size of -0.038mm accounts for 88.76%, the Li2O leaching rate is 95.03%. If the particle size of the roasted ore sample is further increased, the Li2O leaching rate will decrease slightly. Figure 2 As shown, the optimal roasting particle size is -0.038 mm, accounting for 88.86%.
[0049] 3. Calcination time condition test
[0050] The experimental conditions are 10g of ore sample, roasting temperature of 400℃, roasting particle size of -0.038mm accounting for 88.86%, roasting agent concentrated sulfuric acid dosage of 1.1kg / t, leaching temperature of 80℃, leaching time of 1h, oscillation frequency of 150r / min, leaching solid-liquid ratio of 1:3, to explore the effect of roasting time on leaching rate. The experimental data are shown in Table 5.
[0051] Table 5 Calcination time condition test results
[0052]
[0053] When the ore sample is not roasted, the Li2O leaching rate is only 9.38%. When the ore sample is roasted for 0.5h and then leached, the Li2O leaching rate rises sharply to 93.78%. When the roasting time is 1h, the Li2O leaching rate reaches a maximum of 94.44%. As the roasting time increases, the Li2O leaching rate shows a downward trend. Continuing to increase the roasting time has no positive effect on the leaching rate. Figure 3 As shown, the optimal roasting time is 1h.
[0054] 4. Test on the dosage of baking agent
[0055] The experimental conditions are 10g of ore sample, roasting temperature 400℃, roasting particle size -0.038mm accounting for 88.86%, roasting time 1h, leaching temperature 80℃, leaching time 1h, oscillation frequency 150r / min, leaching solid-liquid ratio 1:3, to explore the effect of roasting agent dosage on leaching rate. The experimental data are shown in Table 6.
[0056] Table 6 Test results of calcining agent dosage conditions
[0057]
[0058] When the amount of roasting agent is 0kg / t, the Li2O leaching rate of the blank control test is 15.65%. When the amount of roasting agent concentrated sulfuric acid is 0-0.8kg / t, the Li2O leaching rate also gradually increases. When the amount of roasting agent concentrated sulfuric acid is 0.8kg / t, the Li2O leaching rate is 96.08%, and the test effect is good. When the amount of roasting agent continues to increase, the Li2O leaching rate shows a downward trend and then basically remains stable. Figure 4 As shown in the figure, increasing the amount of roasting agent has no positive effect on the leaching rate, so the optimal amount of roasting agent concentrated sulfuric acid in the experiment is 0.8 kg / t.
[0059] 5. Leaching temperature condition test
[0060] The experimental conditions are as follows: 10 g of ore sample, roasting temperature of 400 ° C, roasting particle size of -0.038 mm accounting for 88.86%, roasting time of 1 h, roasting agent concentrated sulfuric acid dosage of 0.8 kg / t, leaching time of 1 h, oscillation frequency of 150 r / min, leaching solid-liquid ratio of 1:3, to explore the effect of leaching temperature on the leaching rate, the experimental results are shown in Table 7.
[0061] Table 7 Leaching temperature test results
[0062]
[0063] When leaching at room temperature and 25℃, the Li2O leaching rate is only 62.96%. As the leaching temperature gradually increases, the Li2O leaching rate first increases and then decreases, which is consistent with the roasting temperature. The leaching temperature has a greater impact on the leaching rate. Figure 5 When the leaching temperature is 80℃, the Li2O leaching rate is 96.47%, and the leaching effect is good, so the optimal leaching temperature is 80℃.
[0064] 6. Leaching time condition test
[0065] The experimental conditions are as follows: 10 g of ore sample, roasting temperature of 400 ° C, roasting particle size of -0.038 mm accounting for 88.86%, roasting time of 1 h, roasting agent concentrated sulfuric acid dosage of 0.8 kg / t, leaching temperature of 80 ° C, oscillation frequency of 150 r / min, leaching solid-liquid ratio of 1:3, to explore the effect of leaching time on the leaching rate, the experimental results are shown in Table 8.
[0066] Table 8 Leaching time condition test results
[0067]
[0068] When the leaching time is 0h, the Li2O leaching rate is only 22.50%. As the leaching time gradually increases, the Li2O leaching rate shows a trend of first increasing and then decreasing. Figure 6 When the leaching time is 1 hour, the Li2O leaching rate is 95.77%, and the leaching effect is good. When the leaching time is between 1.5 and 2.5 hours, the leaching rate decreases slowly and basically remains stable. Therefore, the optimal leaching time is 1 hour.
[0069] 7. Oscillation frequency condition test
[0070] The experimental conditions are as follows: 10 g of ore sample, roasting temperature of 400 ° C, roasting particle size of -0.038 mm accounting for 88.86%, roasting time of 1 hour, roasting agent concentrated sulfuric acid dosage of 0.8 kg / t, leaching temperature of 80 ° C, leaching time of 1 hour, leaching solid-liquid ratio of 1:3, to explore the effect of oscillation frequency on the leaching rate, the experimental results are shown in Table 9.
[0071] Table 9 Oscillation frequency condition test results
[0072]
[0073] When the oscillation frequency is 0 r / min, the Li2O leaching rate is as high as 93.56%. As the oscillation frequency gradually increases, the Li2O leaching rate shows a trend of first increasing and then decreasing. Figure 7 When the oscillation frequency is 150 r / min, the Li2O leaching rate is 96.32%, which means the leaching effect is good. If the oscillation frequency is further increased, the leaching rate tends to decrease. Therefore, the optimal leaching oscillation frequency is 150 r / min.
[0074] 8. Leaching solid-liquid ratio condition test
[0075] The experimental conditions are 10g of ore sample, roasting temperature of 400℃, roasting particle size of -0.038mm accounting for 88.86%, roasting time of 1h, roasting agent concentrated sulfuric acid dosage of 0.8kg / t, leaching temperature of 80℃, leaching time of 1h, oscillation frequency of 150r / min, to explore the effect of leaching solid-liquid ratio on leaching rate. The experimental results are shown in Table 10.
[0076] Table 10 Leaching solid-liquid ratio test results
[0077]
[0078] As the proportion of leachate gradually increases, the Li2O leaching rate shows a trend of first increasing and then decreasing. Figure 8 When the leaching solid-liquid ratio is 1:4, the Li2O leaching effect is better and the leaching rate can reach 97.31%, so the optimal leaching solid-liquid ratio is 1:4.
[0079] 9. Final optimization test
[0080] The above test results show that the optimal roasting-leaching test conditions are: 10g ore sample, roasting temperature of 400°C, roasting particle size of -0.038mm accounting for 88.86%, roasting time of 1h, roasting agent concentrated sulfuric acid dosage of 0.8kg / t, leaching temperature of 80°C, leaching time of 1h, oscillation frequency of 150r / min, and leaching solid-liquid ratio of 1:4. After optimizing the roasting-leaching factors, optimization tests were conducted, and the results are shown in Table 12.
[0081] Table 12 Optimization test results
[0082]
[0083] Comprehensive data analysis shows that the calcination temperature, ore sample fineness, calcination time, calcining agent dosage, leaching temperature, and leaching time have significant effects on the Li2O leaching rate, while the leaching oscillation frequency and leaching solid-liquid ratio have less influence on the leaching rate. After optimizing the experimental conditions, the Li2O leaching rate remained above 96%, indicating a good leaching effect.
[0084] The above description does not limit the present invention in any form. Any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.
Claims
1. A method for extracting lithium from lithium chlorite ore, characterized in that: The following steps are involved: 1) After the raw ore is crushed, ground, filtered and dried, the ore body particle size is -0.038mm, accounting for 78%-93.65%; 2) Sulfuric acid is mixed with the ore body at a rate of 0.8-2.4 kg / t and roasted at a temperature of 210-500° C. for 0.5-5 h; 3) The calcined reactants are crushed and then mixed with water in a solid-liquid mass ratio of 1:2-1:4, with a constant temperature oscillator having an oscillation frequency of 0-150 r / min, a leaching temperature of 60-90° C., and a leaching time of 0.5-2.5 h.
2. A method for extracting lithium from lithium chlorite ore according to claim 1, characterized in that: In the step 1), the ore body particle size is -0.038 mm, accounting for 88.76%.
3. The method for extracting lithium from lithium chlorite ore according to claim 1, wherein: The calcination temperature in step 2) is 400°C.
4. The method for extracting lithium from lithium chlorite ore according to claim 1, wherein: The calcination time in step 2) is 1 hour.
5. The method for extracting lithium from lithium chlorite ore according to claim 1, wherein: In the step 2), the amount of sulfuric acid used as a roasting agent is mixed with the ore body at 0.8 kg / t.
6. A method for extracting lithium from lithium chlorite ore according to claim 1, characterized in that: The leaching temperature in step 3) is 80°C.
7. The method for extracting lithium from lithium chlorite ore according to claim 1, characterized in that: The leaching time in step 3) is 1 hour.
8. The method for extracting lithium from lithium chlorite ore according to claim 1, characterized in that: In step 3), the constant temperature oscillator has an oscillation frequency of 150 r / min.
9. The method for extracting lithium from lithium chlorite ore according to claim 1, characterized in that: The calcined reactants in step 3) are crushed and then mixed with water at a solid-liquid mass ratio of 1:4.