Oil removal method and application of oil-containing solution
By using diatomaceous earth as an adsorbent for oil removal treatment, the problem of difficulty in removing oil during the extraction process in the prior art is solved, efficient oil removal and protection of valuable metals are achieved, production costs are reduced and environmental pollution is reduced.
Patent Information
- Application Number
- CN202510163445.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-14
- Publication Date
- 2025-05-30
AI Technical Summary
In the prior art, in the extraction process of nickel-cobalt intermediates or retired power battery waste, it is difficult to effectively remove oil in the solution, resulting in poor product quality, and the use of activated carbon increases production costs and difficulty in handling waste materials.
Diatomaceous earth is used as the adsorbent, and the oil in the oil-containing solution is separated out through the adsorption and de-oiling process, and the liquid after de-oiling is obtained through liquid-solid separation. The method also includes a regeneration treatment of the diatomaceous earth adsorbent, which restores the adsorption performance by heating.
The oil removal rate is ≥97%, the loss rate of valuable metals is ≤1%, while reducing production costs, and the recycling of diatomaceous earth reduces environmental pollution.
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of new energy materials, and particularly relates to a method for removing oil from an oil-containing solution and its application. Background Art
[0002] In the field of preparation of cathode materials or recycling of retired power batteries, during the production process using nickel-cobalt intermediate products or retired power battery waste as raw materials, most processes use solvent extraction for impurity removal and purification to produce high-quality nickel sulfate, cobalt sulfate or lithium sulfate solutions. Inevitably, an organic phase will be introduced into the solution produced during the extraction process, making it difficult to meet the usage requirements, and oil removal treatment is required.
[0003] Currently, as a simple and effective method, oil removal using activated carbon is the first choice for many enterprises. However, with the increase in the application fields and usage amounts of activated carbon, the production costs of enterprises have increased significantly, and the waste activated carbon produced has been defined as hazardous waste, and its disposal method has also become a new problem for pollution control for more and more enterprises. Therefore, there is an urgent need to develop a new oil removal method. Summary of the Invention
[0004] In view of the deficiencies of the prior art, the present invention provides a method for removing oil from an oil-containing solution using diatomite as an adsorbent.
[0005] To this end, in the first aspect of the present invention, a method for removing oil from an oil-containing solution is provided, including:
[0006] Passing the oil-containing solution through a diatomite adsorbent for adsorption and oil removal to remove the oil in the oil-containing solution, and then performing liquid-solid separation to obtain an oil-removed liquid;
[0007] Wherein, the oil-containing solution includes: nickel-cobalt hydroxide or nickel sulfate solution, cobalt sulfate solution and / or lithium sulfate solution obtained after extraction treatment of retired power battery cathode materials.
[0008] Further, the oil removal method further includes adsorbent regeneration. The loaded diatomite adsorbent saturated with adsorption is heat-treated at 300°C - 500°C for 0.5 h - 2 h to obtain a regenerated diatomite adsorbent, and the regenerated diatomite adsorbent is continuously used for adsorption and oil removal of the oil-containing solution.
[0009] Further, according to the mass ratio of the diatomite adsorbent to the mass of oil in the oil-containing solution of (30 - 150):1, the oil-containing solution is brought into contact with the diatomite adsorbent for 0.5 h - 1 h.
[0010] Further, in the oil-containing solution, the concentration of oil is not less than 5 mg / L, and the concentration of valuable metal ions is 10 g / L - 150 g / L.
[0011] Further, the oil removal method includes:
[0012] Fill the diatomite adsorbent into a filter press. The oil-containing solution passes through the filter press for oil removal. The defatted solution flows out directly from the filter press, and the loaded diatomite adsorbent after adsorption remains in the filter press until it is saturated with adsorption and then sent for regeneration.
[0013] Furthermore, the oil removal method includes single-stage adsorption or multi-stage adsorption.
[0014] Even further, the single-stage adsorption includes:
[0015] The oil-containing solution is subjected to one-step oil removal. The diatomite adsorbent is filled into a first filter press. The oil-containing solution directly passes through the first filter press for oil removal. The defatted solution flows out directly from the first filter press, and the loaded diatomite adsorbent after adsorption remains in the first filter press until it is saturated with adsorption and then sent for regeneration.
[0016] Even further, the multi-stage adsorption includes:
[0017] The oil-containing solution is subjected to two-step oil removal. The diatomite adsorbent is filled into a first filter press and a second filter press respectively. The oil-containing solution first passes through the first filter press for oil removal. The filtrate flowing out from the first filter press enters the second filter press for secondary oil removal to obtain the defatted solution. The loaded diatomite adsorbent after adsorption remains in the first filter press and the second filter press until it is saturated with adsorption and then sent for regeneration.
[0018] Furthermore, through the oil removal method, the removal rate of oil in the oil-containing solution is ≥97%, and the loss rate of valuable metals in the oil-containing solution is ≤1%.
[0019] In the second aspect of the present invention, an application of an oil removal method for an oil-containing solution is provided. The above oil removal method is used in the field of preparation of cathode materials or recycling of retired power batteries.
[0020] Compared with the prior art, the present invention has at least the following beneficial effects:
[0021] (1) The present invention uses a diatomite adsorbent for oil removal, skillfully utilizes the adsorption and synergistic effects of diatomite, has good adsorption and removal effects, the removal rate of oil is ≥97%, has little influence on the loss of valuable metals, and the loss rate of valuable metals is ≤1%; and diatomite is inexpensive and can be recycled, achieving the purpose of energy conservation and consumption reduction.
[0022] (2) The present invention can directly fill the diatomite adsorbent into a filter press, and the oil-containing solution can be directly defatted through the filter press, with high oil removal efficiency and high utilization rate of the diatomite adsorbent.
[0023] (3) The present invention is an efficient, green, environmentally friendly and sustainable oil removal method, which has the advantages of simple process, low cost, easy operation, clean environmental protection and good oil removal effect. The required equipment is simple, green and environmentally friendly, and is easy to be applied on a large scale. It is suitable for the oil removal treatment of oil-containing solutions in the field of new energy materials. Detailed implementation manners
[0024] In order to better understand the above technical solution, the technical solution of the present application will be described in detail through specific embodiments below.
[0025] In the first aspect of the embodiment of the present invention, an oil removal method for an oil-containing solution is provided, including:
[0026] Pass the oil-containing solution through a diatomite adsorbent for adsorption and oil removal, remove the oil in the oil-containing solution, and then perform liquid-solid separation to obtain the post-oil removal liquid, thus completing the oil removal.
[0027] Among them, the oil-containing solution includes: nickel-cobalt hydroxide or nickel sulfate solution, cobalt sulfate solution and / or lithium sulfate solution obtained by extraction treatment of the positive electrode material of retired power batteries.
[0028] The oil removal method for the oil-containing solution provided by the present invention is an efficient, green, environmentally friendly and sustainable oil removal method, which has the advantages of simple process, low cost, easy operation, clean environmental protection and good oil removal effect. The required equipment is simple, green and environmentally friendly, and is easy to be applied on a large scale. It is suitable for the oil removal treatment of oil-containing solutions in the field of new energy materials. The diatomite adsorbent is used for oil removal, and the adsorption and synergistic effects of the diatomite are skillfully utilized, and the adsorption and removal effect is good. The removal rate of oil is ≥97%, and the influence on the loss of valuable metals is small, and the loss rate of valuable metals is ≤1%; and the diatomite is low in price and can be recycled, achieving the purpose of energy conservation and consumption reduction.
[0029] In a feasible implementation manner, the oil removal method further includes adsorbent regeneration. The loaded diatomite adsorbent saturated with adsorption is heat-treated at 300°C - 500°C to obtain a regenerated diatomite adsorbent, and the regenerated diatomite adsorbent is continuously used for the adsorption and oil removal of the oil-containing solution.
[0030] It can be understood that the oil-containing solution is passed through the diatomite adsorbent for adsorption and oil removal, and then liquid-solid separation is performed to obtain the post-oil removal liquid and the loaded diatomite adsorbent. When the loaded diatomite adsorbent is not saturated with adsorption, it can be continuously used for oil removal until it is saturated with adsorption. Whether the loaded diatomite adsorbent is saturated with adsorption can be comprehensively judged by calculating the adsorption capacity, the oil content of the post-oil removal liquid and the appearance of the diatomite. When the diatomite adsorbent has reached saturation, the saturated diatomite adsorbent is separated and subjected to heat regeneration treatment to restore the adsorption performance of the diatomite and then recycled.
[0031] Specifically, we studied the method for regenerating the diatomite adsorbent and found that heating at a temperature of 300°C - 500°C for 0.5 h - 2 h can stably regenerate the saturated diatomite adsorbent.
[0032] In a feasible embodiment, the mass ratio of the diatomite adsorbent to the oil in the oil-containing solution is (30 - 150):1, and the oil-containing solution is contacted with the diatomite adsorbent for 0.5 h - 1 h.
[0033] Specifically, when using the diatomite adsorbent for oil adsorption and removal, the mass ratio of the diatomite adsorbent to the oil in the oil-containing solution is (30 - 150):1, and the oil-containing solution is contacted with the diatomite adsorbent for 0.5 h - 1 h. The oil removal rate is higher than 97%, and the loss rate of valuable metals is less than 1%. If the mass ratio of the diatomite adsorbent to the oil in the oil-containing solution is less than 30:1, the amount of the diatomite adsorbent is insufficient, making it difficult to effectively remove the oil in the oil-containing solution, resulting in a low oil removal rate. If the mass ratio of the diatomite adsorbent to the oil in the oil-containing solution is greater than 150:1, the amount of the diatomite adsorbent is excessive, increasing the treatment cost. When the adsorption time is less than 0.5 h, the contact time between the oil and the diatomite adsorbent is short, resulting in poor adsorption effect. When the adsorption time exceeds 1 h, the long adsorption time affects the oil removal efficiency. In addition, the temperature has little effect on the oil removal effect and can be ignored.
[0034] In a feasible embodiment, in the oil-containing solution, the concentration of the oil is not less than 5 mg / L, and the concentration of the valuable metal ions is 10 g / L - 150 g / L.
[0035] Specifically, the oil removal method of the present invention is applicable to an oil-containing solution with an oil concentration of not less than 5 mg / L and a valuable metal ion concentration of 10 g / L - 150 g / L, and can obtain a good removal effect, with an oil removal rate ≥ 97% and a valuable metal loss rate ≤ 1%.
[0036] In a feasible embodiment, the oil removal method includes:
[0037] Filling the diatomite adsorbent into a filter press, passing the oil-containing solution through the filter press for oil removal, and the defatted liquid directly flows out of the filter press, while the loaded diatomite adsorbent after adsorption remains in the filter press until it is saturated with adsorption and then sent for regeneration.
[0038] Specifically, directly filling the diatomite adsorbent into the filter press, the oil-containing solution can be directly passed through the filter press for oil removal, with high oil removal efficiency and high utilization rate of the diatomite adsorbent. Moreover, the equipment is simple, the operation is simple, it is environmentally friendly and easy to be applied on a large scale.
[0039] In a feasible embodiment, the oil removal method includes single-stage adsorption or multi-stage adsorption.
[0040] Among them, single-stage adsorption includes:
[0041] The oil-containing solution is subjected to one-step oil removal. The diatomite adsorbent is filled into the first filter press, and the oil-containing solution directly passes through the first filter press for oil removal. The deoiled liquid flows out directly from the first filter press, and the loaded diatomite adsorbent after adsorption remains in the first filter press until it is saturated with adsorption and then sent for regeneration.
[0042] Among them, multi-stage adsorption includes:
[0043] The oil-containing solution is subjected to two-step oil removal. The diatomite adsorbent is filled into the first filter press and the second filter press respectively. The oil-containing solution first passes through the first filter press for oil removal, and the filtrate flowing out from the first filter press enters the second filter press for secondary oil removal. The deoiled liquid flows out from the second filter press, and the loaded diatomite adsorbent after adsorption remains in the first filter press and the second filter press until it is saturated with adsorption and then sent for regeneration.
[0044] In the second aspect of the embodiments of the present invention, an application of an oil removal method for an oil-containing solution is provided. The above oil removal method has a wide application range and strong adaptability, and is suitable for the oil removal treatment of oil-containing solutions in the field of new energy materials, including but not limited to being used in the fields of cathode material preparation or recycling of retired power batteries.
[0045] Example 1
[0046] An oil removal method for an oil-containing solution includes the following steps:
[0047] (1) Take 1 m of nickel sulfate solution with an oil concentration of 40 mg / L and a Ni concentration of 115 g / L 3 , and fill the diatomite adsorbent into the filter press according to the mass ratio of oil to diatomite adsorbent in the oil-containing solution of 1:50. At room temperature, the nickel sulfate solution passes through the filter press for oil removal, and after adsorption for 0.5 h, a loaded diatomite adsorbent and a deoiled liquid are obtained.
[0048] After testing, the nickel concentration in the deoiled liquid is 114.7 g / L, the oil concentration drops to 1.1 mg / L, the oil removal rate is 97.25%, and the nickel loss rate is 0.26%.
[0049] (2) Heat the loaded diatomite adsorbent after adsorption saturation, control the heating temperature at 300 °C, obtain a regenerated diatomite adsorbent, and the regenerated diatomite adsorbent returns to step (1) for recycling.
[0050] Example 2
[0051] An oil removal method for an oil-containing solution includes the following steps:
[0052] (1) Take 1 m of cobalt sulfate solution with an oil concentration of 30 mg / L and a Co concentration of 120 g / L 3, fill the diatomite adsorbent into the filter press according to the mass ratio of oil to diatomite adsorbent in the oil-containing solution of 1:50. At room temperature, the cobalt sulfate solution passes through the filter press for oil removal. After adsorption for 0.5 h, the loaded diatomite adsorbent and the oil-removed liquid are obtained.
[0053] After testing, the cobalt concentration in the oil-removed liquid is 119.5 g / L, the oil concentration drops to 0.9 mg / L, the oil removal rate is 97.0%, and the cobalt loss rate is 0.42%.
[0054] (2) Heat-treat the loaded diatomite adsorbent after adsorption saturation. Control the heating temperature at 400 °C to obtain the regenerated diatomite adsorbent, and the regenerated diatomite adsorbent returns to step (1) for recycling.
[0055] Example 3
[0056] An oil removal method for an oil-containing solution, comprising the following steps:
[0057] (1) Take 1 m of lithium sulfate solution with an oil concentration of 30 mg / L and a Li concentration of 20 g / L 3 , fill the diatomite adsorbent into the filter press according to the mass ratio of oil to diatomite adsorbent in the oil-containing solution of 1:50. At room temperature, the lithium sulfate solution passes through the filter press for oil removal. After adsorption for 0.5 h, the loaded diatomite adsorbent and the oil-removed liquid are obtained.
[0058] After testing, the lithium concentration in the oil-removed liquid is 19.9 g / L, the oil concentration drops to 0.8 mg / L, the oil removal rate is 97.33%, and the nickel loss rate is 0.5%.
[0059] (2) Heat-treat the loaded diatomite adsorbent after adsorption saturation. Control the heating temperature at 500 °C to obtain the regenerated diatomite adsorbent, and the regenerated diatomite adsorbent returns to step (1) for recycling.
[0060] Example 4
[0061] An oil removal method for an oil-containing solution, comprising the following steps:
[0062] Take 1 m of nickel sulfate solution with an oil concentration of 40 mg / L and a Ni concentration of 115 g / L 3 , fill the diatomite adsorbent into two filter presses respectively according to the mass ratio of oil to diatomite adsorbent in the oil-containing solution of 1:50. At room temperature, the nickel sulfate solution passes through the first filter press for oil removal. After adsorption for 0.5 h, the filtrate then flows through the second filter press for oil removal. After adsorption for 0.3 h, the oil-removed liquid is obtained.
[0063] After testing, the nickel concentration in the oil-removed liquid is 114.5 g / L, the oil concentration drops to 0.5 mg / L, the oil removal rate is 98.75%, and the nickel loss rate is 0.43%.
[0064] In summary, the diatomite adsorbent has good oil removal effect on the oil-containing solution. The oil removal effect of two-stage adsorption is better than that of single-stage adsorption, and the metal loss rate of two-stage adsorption is slightly higher than that of single-stage adsorption. The oil removal method of the present invention has a high oil removal rate and a low metal loss rate.
[0065] It is easy for those skilled in the art to understand that, on the premise of no conflict, the above-mentioned advantageous ways can be freely combined and superimposed. The above is only a preferred embodiment of the present application, and it is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application. The above is only the preferred implementation manner of the present application. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present application, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present application.
Claims
1. A method for removing oil from an oily solution, characterized in that: include: The oil-containing solution is subjected to adsorption and deoiling by a diatomaceous earth adsorbent to remove the oil in the oil-containing solution, and then subjected to liquid-solid separation to obtain a deoiled liquid; The oil-containing solution includes: nickel sulfate solution, cobalt sulfate solution and / or lithium sulfate solution obtained by extraction treatment of nickel cobalt hydroxide or retired power battery positive electrode materials.
2. The method for removing oil from an oil-containing solution according to claim 1, characterized in that: The method also includes regenerating the adsorbent, heating the saturated loaded diatomaceous earth adsorbent at 300° C.-500° C. for 0.5 h-2 h to obtain a regenerated diatomaceous earth adsorbent, and the regenerated diatomaceous earth adsorbent is continuously used for adsorption and deoiling of the oil-containing solution.
3. The method for removing oil from an oil-containing solution according to claim 1, characterized in that: The oil-containing solution is contacted with the diatomaceous earth adsorbent for 0.5 h to 1 h according to the mass ratio of the diatomaceous earth adsorbent to the mass ratio of the oil in the oil-containing solution (30-150):
1.
4. The method for removing oil from an oil-containing solution according to claim 3, characterized in that: In the oil-containing solution, the concentration of oil is not less than 5 mg / L, and the concentration of valuable metal ions is 10 g / L-150 g / L.
5. The method for removing oil from an oil-containing solution according to claim 4, characterized in that: The oil removal method comprises: The diatomaceous earth adsorbent is filled into a filter press, the oil-containing solution is deoiled through the filter press, the deoiled liquid directly flows out of the filter press, and the adsorbed loaded diatomaceous earth adsorbent remains in the filter press until it is saturated with adsorption and then sent for regeneration.
6. The method for removing oil from an oil-containing solution according to claim 5, characterized in that: The oil removal method includes single-stage adsorption or multi-stage adsorption.
7. The method for removing oil from an oil-containing solution according to claim 6, characterized in that: The single-stage adsorption comprises: The oil-containing solution is subjected to a step of deoiling, and the diatomaceous earth adsorbent is filled into a first filter press. The oil-containing solution directly passes through the first filter press for deoiling, and the deoiled liquid directly flows out of the first filter press. The adsorbed loaded diatomaceous earth adsorbent remains in the first filter press until it is saturated with adsorption and then sent for regeneration.
8. The method for removing oil from an oil-containing solution according to claim 6, characterized in that: The multi-stage adsorption comprises: The oil-containing solution is subjected to two-step oil removal, and the diatomaceous earth adsorbent is respectively filled into the first filter press and the second filter press, the oil-containing solution first passes through the first filter press for oil removal, and the filtrate flowing out of the first filter press enters the second filter press for secondary oil removal to obtain the deoiled liquid, and the adsorbed loaded diatomaceous earth adsorbent remains in the first filter press and the second filter press until the adsorption is saturated and then sent for regeneration.
9. The method for removing oil from an oil-containing solution according to any one of claims 1 to 8, characterized in that: After the oil removal method, the oil removal rate in the oil-containing solution is ≥97%, and the loss rate of valuable metals in the oil-containing solution is ≤1%.
10. Application of a method for removing oil from an oily solution, characterized in that: The oil removal method according to any one of claims 1 to 9 is used in the field of positive electrode material preparation or retired power battery recycling.