Method for improving the oil removal effect of activated carbon on separation and purification of output liquid

Abstract

The invention discloses a method for improving the deoiling effect of activated carbon on separation and purification output liquid, and relates to the technical field of solution deoiling in separation and purification production. The method for improving the deoiling effect of activated carbon on separation and purification output liquid is carried out according to the following steps: S1, placing the activated carbon in a high-temperature furnace, introducing protective gas after vacuuming, heating to 1000-1200°C, introducing methane after reaching the target temperature, keeping the temperature in the methane atmosphere for 1-3 hours, cooling to room temperature with the furnace, and obtaining an activated carbon treated product; S2, the activated carbon treated product obtained in step S1 is used as a filler or directly put into a solution to deoil the separation and purification output liquid. High-efficiency removal of oil pollution is achieved to prevent oil pollution from affecting the quality of the product.

Description

Technical Field

[0001] The invention relates to the technical field of solution deoiling in separation and purification production, and in particular to a method for improving the deoiling effect of activated carbon on separation and purification output liquid. Background Art

[0002] The separation and purification process is an important process link in the preparation of precursor materials. The residual problem of extractants and solvent oil in the separation and purification production has caused a series of problems in subsequent production. Taking the nickel sulfate solution produced by separation and purification as an example, nickel sulfate solution is the main raw material for the preparation of lithium battery ternary precursors. Organic matter remaining in the salt solution will seriously affect the synthesis of the precursor, resulting in loose morphology, inability to form balls, wide particle size distribution, and decreased tap density during the precipitation process. Therefore, special organic matter introduced in the separation and purification production process needs to be purified. Activated carbon, as an important adsorption material in the oil removal system, is widely used in separation, purification and oil removal. Activated carbon adsorption mainly uses the capillary principle and the physical cohesion between molecules to adsorb oil, or absorbs oil into the interior and swells itself to remove oil.

[0003] In the prior art, the invention patent application with publication number CN112604664A discloses a low-ash activated carbon for degreasing condensed water. It uses activated carbon as a matrix and loads the active component polynicotinate chromium. The activated carbon is mainly treated with acid and alkali to attach polynicotinate chromium to improve the product's water repellency and degreasing efficiency. It is different from the treatment method of the present invention and introduces other components.

[0004] The invention patent application with publication number CN112408389A discloses a method for preparing activated carbon from oil-tea camellia shells and activated carbon from oil-tea camellia shells. The activated carbon material is prepared from oil-tea camellia shells as a raw material for adsorption. The activated carbon is mainly prepared from oil-tea camellia shells. The treated material is fixed, which is different from the present invention. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for improving the oil removal effect of activated carbon on the separation and purification of output liquid, wherein the activated carbon is subjected to high-temperature treatment in a methane gas atmosphere, which can improve the activated carbon's adsorption capacity for oil components in the solution, thereby reducing the impact of impurities.

[0006] To achieve this technical purpose, the present invention adopts the following scheme:

[0007] The method for improving the oil removal effect of activated carbon on the separation and purification of the output liquid is carried out according to the following steps:

[0008] S1. Place the activated carbon in a high-temperature furnace, introduce protective gas after evacuation, heat to 1000-1200°C, introduce methane after reaching the target temperature, keep warm in the methane atmosphere for 1-3 hours, cool to room temperature with the furnace, and obtain an activated carbon treated product;

[0009] S2. The activated carbon treated material obtained in step S1 is used as a filler or directly added into a solution to remove oil from the separated and purified output liquid.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] 1. The scheme of the present invention aims to make the activated carbon contact with the pore surface of the activated carbon as a carbon source and catalyst in a high-temperature methane atmosphere, realize graphitization of the pore surface while retaining a rich pore structure, and improve the hydrophobicity and lipophilicity of the material to improve the oil removal effect of the activated carbon.

[0012] 2. The present invention uses methane as the reaction gas, and the tail gas produced can be reused after being removed from impurities and dried, which is environmentally friendly. It does not introduce other impurities, and will not cause secondary pollution to the solution after being used for degreasing the solution, and does not change the use of the process after separating and purifying the liquid.

[0013] 3. This solution has a simple process and can realize automated production.

[0014] The preferred embodiment of the present invention is:

[0015] The protective gas in S1 is one of argon or nitrogen.

[0016] The activated carbon treated by S1 is any one of wood powdered activated carbon, coconut shell powdered activated carbon, apricot shell columnar activated carbon or coal columnar activated carbon, and its specific surface area is 1000~2000m 2 / g, and the average pore size is 0.5~5nm.

[0017] The hydrogen atmosphere in S1 refers to the volume V of the reaction container as a reference, and the hydrogen flow rate is 0.5V / h~2V / h.

[0018] The separated and purified output liquid in S2 refers to the aqueous phase liquid produced after the liquid-liquid separation and purification process, and after oil-water mixing and phase separation. The aqueous phase solution is a sulfate solution or a chloride solution. The ion concentration in the salt solution has a negligible effect on the oil removal effect. DETAILED DESCRIPTION

[0019] Figure 1 The XRD diagrams of the products of Example 1 and Comparative Example 1 of the present invention are shown in FIG. DETAILED DESCRIPTION

[0021] In order to fully understand the purpose, features and effects of the present invention, the present invention is described in detail through the following specific implementation methods, but the present invention is not limited thereto.

[0022] Embodiment 1:

[0023] Place wood powdered activated carbon in a 10L quartz tube, introduce nitrogen through the sealed vacuum port and heat to 1000℃. After reaching the temperature, introduce methane at a flow rate of 20L / h and keep warm for 3h. After the time is up, cool down to room temperature with the furnace. Take 5g of the prepared activated carbon and stir it in 100L of separated and purified nickel sulfate solution for 2h, and check the oil and COD content of the liquid before and after nickel sulfate degreasing. The index of the liquid after is significantly lower than that of the liquid before, and the activated carbon shows a good degreasing effect.

[0024] Embodiment 2:

[0025] Place coconut shell powdered activated carbon in a 10L quartz tube, close the vacuum port and introduce argon to raise the temperature to 1000℃, then introduce methane at a flow rate of 20L / h after reaching the temperature, and keep warm for 3h. Make an activated carbon column, introduce 500L of manganese sulfate solution produced by separation and purification, and introduce liquid at a flow rate of 5L / h to check the oil and COD content in the liquid before and after manganese sulfate degreasing. The index of the liquid after is significantly lower than that of the liquid before, and the activated carbon shows a good degreasing effect.

[0026] Embodiment 3:

[0027] Place the apricot shell columnar activated carbon in a 10L quartz tube, close the vacuum port and introduce nitrogen to raise the temperature to 1000℃. After reaching the temperature, introduce methane at a flow rate of 20L / h and keep warm for 3h. After the time is up, cool it down to room temperature with the furnace. Take 5g of the prepared activated carbon and stir it in 100L of separated and purified cobalt chloride liquid for 2h, and check the oil and COD content of the liquid before and after cobalt chloride degreasing. The index of the liquid after is significantly lower than that of the liquid before, and the activated carbon shows a good degreasing effect.

[0028] Embodiment 4:

[0029] Put the coal-made columnar activated carbon in a 10L quartz tube, close the vacuum port and introduce nitrogen to raise the temperature to 1000℃, then introduce methane at a flow rate of 20L / h after reaching the temperature, and keep warm for 3h. After the time is up, cool down to room temperature with the furnace. Take 5g of the prepared activated carbon and stir it in 100L of magnesium sulfate liquid produced by separation and purification for 2h, and check the oil and COD content of the liquid before and after magnesium sulfate degreasing. The index of the liquid after is significantly lower than that of the liquid before, and the activated carbon shows a good degreasing effect.

[0030] Embodiment 5:

[0031] Place wood powdered activated carbon in a 10L quartz tube, introduce nitrogen through the sealed vacuum port and heat to 1000℃. After reaching the temperature, introduce methane at a flow rate of 5L / h and keep warm for 3h. After the time is up, cool down to room temperature with the furnace. Take 5g of the prepared activated carbon and stir it in 100L of separated and purified nickel sulfate liquid for 2h, and check the oil and COD content before and after nickel sulfate degreasing. The index of the after liquid is significantly lower than that of the before liquid, and the activated carbon shows a good degreasing effect.

[0032] Embodiment 6:

[0033] Put the wood powdered activated carbon in a 10L quartz tube, close the vacuum port and introduce nitrogen to raise the temperature to 1200℃, then introduce methane at a flow rate of 20L / h after reaching the temperature, and keep warm for 3h. After the time is up, cool down to room temperature with the furnace. Take 5g of the prepared activated carbon and stir it in 100L of sodium sulfate solution produced by separation and purification for 2h, and check the oil and COD content of the liquid before and after sodium sulfate degreasing. The index of the liquid after is significantly lower than that of the liquid before, and the activated carbon shows a good degreasing effect.

[0034] Embodiment 7:

[0035] Put the wood powdered activated carbon in a 10L quartz tube, close the vacuum port and introduce nitrogen to raise the temperature to 1200℃. After reaching the temperature, introduce methane at a flow rate of 20L / h and keep warm for 1h. After the time is up, cool it down to room temperature with the furnace. Take 5g of the prepared activated carbon and stir it in 100L of sodium sulfate liquid produced by separation and purification for 2h, and check the oil and COD content of the liquid before and after sodium sulfate degreasing. The index of the liquid after is significantly lower than that of the liquid before, and the activated carbon shows a good degreasing effect.

[0036] Embodiment 8:

[0037] Put the wood powdered activated carbon in a 10L quartz tube, close the vacuum port and introduce nitrogen to raise the temperature to 1100℃, then introduce methane at a flow rate of 20L / h after reaching the temperature, and keep warm for 1h. After the time is up, cool down to room temperature with the furnace. Take 5g of the prepared activated carbon and stir it in 100L of sodium chloride solution produced by separation and purification for 2h, and check the oil and COD content of the liquid before and after sodium chloride degreasing. The index of the liquid after is significantly lower than that of the liquid before, and the activated carbon shows a good degreasing effect.

[0038] Comparative Example 1:

[0039] 5g of untreated wood powdered activated carbon was added to 100L of separated and purified nickel sulfate solution and stirred for 2h, and the liquid oil and COD content before and after nickel sulfate deoiling were checked. Compared with Example 1, the liquid oil content increased by 1.64mg / L and the COD content increased by 61.64mg / L after deoiling, and the deoiling effect of activated carbon after treatment in Example 1 was significantly improved.

[0040] Comparative Example 2:

[0041] Place coconut shell powdered activated carbon in a 10L quartz tube, close the vacuum port and introduce nitrogen to raise the temperature to 1000°C, introduce hydrogen at a flow rate of 20L / h after reaching the temperature, and keep warm for 3h. Make an activated carbon column, pass 500L of separated and purified manganese sulfate solution, and introduce liquid at a flow rate of 5L / h to check the oil and COD content in the liquid before and after manganese sulfate degreasing. Compared with Example 2, the oil content of the liquid after degreasing increased by 4.44mg / L, and the COD content increased by 190.93mg / L. The degreasing effect of activated carbon after treatment in Example 2 was significantly improved.

[0042] Comparative Example 3:

[0043] Place wood powdered activated carbon in a 10L quartz tube, introduce nitrogen through the sealed vacuum port and heat to 1000°C, introduce hydrogen at a flow rate of 20L / h after reaching the temperature, and keep warm for 3h. Cool down to room temperature with the furnace after the time is up. Take 5g of the obtained activated carbon and stir it in 100L of separated and purified nickel sulfate liquid for 2h, and check the liquid oil and COD content before and after nickel sulfate degreasing. Compared with Example 1, the liquid oil content increased by 3.00mg / L after degreasing, and the COD content increased by 120.46mg / L. The degreasing effect of activated carbon after treatment in Example 1 was significantly improved.

[0044] Table 1 Comparison of liquid oil and COD test results before and after activated carbon deoiling in Examples 1-8 and Comparative Examples 1-3

[0045]

[0046] XRD analysis of activated carbon samples before and after treatment is performed, see Figure 1 ; Example 1 and Comparative Example 1 have a broadened diffraction peak at 26° (2θ), which corresponds to the (002) diffraction peak of amorphous carbon; at the same time, the activated carbon material of Example 1 has a strong diffraction peak at 26° (2θ), which corresponds to the (002) diffraction peak of ordered graphite. This shows that the activated carbon has an ordered graphite structure after treatment.

[0047] Finally, it should be noted that the above are only preferred embodiments of the present invention. Of course, those skilled in the art can make changes and modifications to the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalent technologies, they should be considered to be within the scope of protection of the present invention.

Claims

1. A method for improving the oil removal effect of activated carbon on separation and purification of output liquid, characterized in that: Proceed as follows: S1. Place wood powdered activated carbon in a high-temperature furnace, evacuate and introduce nitrogen, heat to 1200°C, introduce methane at a flow rate of 20 L / h after reaching the target temperature, keep warm in the methane atmosphere for 3 hours, cool to room temperature with the furnace, and obtain an activated carbon treated product; S2. The activated carbon treated product obtained in step S1 is directly put into the solution to remove oil from the separated and purified output liquid.

2. The method for improving the oil removal effect of activated carbon on separation and purification of output liquid according to claim 1, characterized in that: The separated and purified output liquid in S2 refers to the aqueous phase liquid produced after the liquid-liquid separation and purification process, and the oil-water mixing and phase separation. The aqueous phase solution is a sulfate solution or a chloride solution.

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