阅读说明：本技术 一种提高电容炭的纯度的方法 (Method for improving purity of capacitance carbon ) 是由 袁淑霞 周敬杰 于 2021-08-24 设计创作，主要内容包括：本发明是关于一种提高电容炭的纯度的方法,涉及电容炭技术领域。主要采用的技术方案为：一种提高电容炭的纯度的方法,其包括如下步骤：室温下,将电容炭分散于去离子水中,得到混合液；采用两性离子交换树脂颗粒对所述混合液中的电容炭进行脱杂处理,脱除所述电容炭中的阳离子杂质和阴离子杂质,得到提纯后的电容炭；其中,所述两性离子交换树脂颗粒的离子型式为氢型和氢氧型。本发明主要用于采用两性离子交换树脂颗粒一步法同时实现对电容炭中的阳离子杂质和阴离子杂质的去除,大幅提高了电容炭的纯度,并且操作步骤简单、实验条件温和、成本低廉、环境友好,适合工业化使用。(The invention relates to a method for improving the purity of capacitance carbon, and relates to the technical field of capacitance carbon. The main technical scheme adopted is as follows: a method for improving the purity of capacitance carbon comprises the following steps: dispersing capacitance carbon in deionized water at room temperature to obtain a mixed solution; adopting amphoteric ion exchange resin particles to carry out impurity removal treatment on the capacitance carbon in the mixed solution, and removing cation impurities and anion impurities in the capacitance carbon to obtain purified capacitance carbon; wherein the ion type of the amphoteric ion exchange resin particles is hydrogen type and hydroxide type. The method is mainly used for simultaneously removing the cationic impurities and the anionic impurities in the capacitance carbon by adopting the amphoteric ion exchange resin particle one-step method, greatly improves the purity of the capacitance carbon, has simple operation steps, mild experimental conditions, low cost and environmental friendliness, and is suitable for industrial use.)

1. A method for improving the purity of capacitance carbon is characterized by comprising the following steps:

preparing a mixed solution: dispersing capacitance carbon in deionized water to obtain a mixed solution;

impurity removal treatment: adopting amphoteric ion exchange resin particles to carry out impurity removal treatment on the capacitance carbon in the mixed solution, and removing cation impurities and anion impurities in the capacitance carbon to obtain purified capacitance carbon; wherein the ion type of the amphoteric ion exchange resin particles is hydrogen type and hydroxide type.

2. The method of increasing the purity of capacitive carbon of claim 1, wherein in the step of dedoping: and removing cation impurities and anion impurities in the capacitance carbon by adopting a static ion exchange mode, which specifically comprises the following steps:

adding the amphoteric ion exchange resin particles into the mixed solution, fully mixing for a set time, filtering the amphoteric ion exchange resin particles by using a filter screen, and performing suction filtration on the filtrate; and directly drying the filter cake obtained after the suction filtration treatment to obtain the purified capacitance carbon.

3. The method for improving the purity of the capacitance carbon as claimed in claim 2, wherein the particle size of the capacitance carbon is 0.1mm or less; the particle size of the amphoteric ion exchange resin particles is 0.15-0.8 mm; the mesh number of the filter screen is 20-100 meshes.

4. The method for increasing the purity of capacitance carbon according to claim 2 or 3,

the amphoteric ion exchange resin particles comprise strong-acid ion exchange resin particles and strong-base ion exchange resin particles; wherein the ratio of the strong acidic ion exchange resin particles to the strong basic ion exchange resin particles is (0.85-0.9): 1; preferably, the strongly acidic ion exchange resin particles are hydrogen type ion exchange resin particles, and the strongly basic ion exchange resin particles are hydroxide type ion exchange resin particles; further preferably, the mass ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is (0.5 to 1.5): 2, preferably 1: 2; and/or

The mass ratio of the amphoteric ion exchange resin particles to the capacitance carbon is (0.1-10): 1.

5. The method for improving the purity of the capacitance carbon as claimed in any one of claims 2 to 4, wherein the manner of the intensive mixing treatment is selected from stirring treatment; wherein the set time is 1-12h, and the stirring speed is 60-180 r/min.

6. The method of increasing the purity of capacitive carbon of claim 1, wherein in the step of dedoping: and removing cation impurities and anion impurities in the capacitance carbon by adopting a dynamic ion exchange mode, and specifically comprises the following steps:

making the mixed solution flow through an ion exchange column filled with amphoteric ion exchange resin particles to carry out ion exchange treatment, and collecting effluent liquid; and carrying out suction filtration on the effluent liquid, and directly drying a filter cake obtained after the suction filtration to obtain the purified capacitance carbon.

7. The method of increasing the purity of capacitive carbon of claim 6,

the particle size of the amphoteric ion exchange resin particles is 0.15-0.8 mm;

preferably, the amphoteric ion exchange resin particles include strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles; wherein the ratio of the strong acidic ion exchange resin particles to the strong basic ion exchange resin particles is (0.85-0.9): 1;

preferably, in the amphoteric ion exchange resin particles: the particle sizes of all strong acid ion exchange resin particles are the same, and the particle sizes of all strong base ion exchange resin particles are the same;

preferably, the strongly acidic ion exchange resin particles are hydrogen type ion exchange resin particles, and the strongly basic ion exchange resin particles are hydroxide type ion exchange resin particles; further preferably, the mass ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is (0.5 to 1.5): 2, preferably 1: 2.

8. The method of increasing the purity of capacitive carbon of any one of claims 1-7, wherein the step of formulating a mixed liquor is performed at room temperature; and/or

In the impurity removal treatment step, the step of performing ion exchange on the cation impurities and the anion impurities of the capacitance carbon by using the amphoteric ion exchange resin particles is performed at room temperature.

9. The method for increasing the purity of capacitive carbon according to any one of claims 1 to 8, further comprising, after the step of dedoping, the steps of:

a regeneration treatment step: carrying out regeneration treatment on the amphoteric ion exchange resin particles after impurity removal treatment;

preferably, the amphoteric ion exchange resin is separated into strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles by using the difference in density, and then subjected to regeneration treatment separately.

10. The method for increasing the purity of capacitance carbon according to any one of claims 1-9, wherein in the purified capacitance carbon:

the content of Fe element is not more than 50mg/kg, preferably not more than 44.9mg/kg, and further preferably not more than 43.5 mg/kg;

the content of Ni element is not more than 50mg/kg, preferably not more than 2.1mg/kg, and further preferably not more than 1.8 mg/kg;

the content of Co element is not more than 20mg/kg, preferably not more than 0.7mg/kg, and more preferably not more than 0.5 mg/kg;

the content of Cu element is not more than 20mg/kg, preferably not more than 5.4mg/kg, and further preferably not more than 4.9 mg/kg;

the content of Na element is not more than 100mg/kg, preferably not more than 62.7mg/kg, and further preferably not more than 56.1 mg/kg;

the content of K element is not more than 200mg/kg, preferably not more than 64.4mg/kg, and further preferably not more than 58.9 mg/kg;

the content of Al element is not more than 200mg/kg, preferably not more than 98.3mg/kg, and further preferably not more than 85.6 mg/kg;

Cl^-the content is not more than 20mg/kg, preferably not more than 18mg/kg, and further preferably not more than 16 mg/kg;

SO₄ ^2-the content is not more than 10mg/kg, preferably not more than 9mg/kg, and further preferably not more than 8 mg/kg;

NO₃ ^-the content is not more than 10mg/kg, preferably not more than 8mg/kg, and further preferably not more than 6 mg/kg.

Technical Field

The invention relates to the technical field of capacitance carbon, in particular to a method for improving the purity of the capacitance carbon.

Background

As an efficient, economic, safe and reliable electrochemical energy storage device, the super capacitor has the core advantage of ultra-long cycle stability, so that the commercialized super capacitor has high requirements on the purity of electrode materials thereof, and GB/T37386-2019 activated carbon for super capacitors contains a plurality of metal elements (iron, nickel, cobalt, copper, sodium, potassium and aluminum) and anions (Cl)^-、SO₄ ^2-、NO₃ ^-) The upper limit index is given by the content of the impurities.

At present, in the preparation method of the conventional supercapacitor activated carbon (i.e. capacitance carbon), the impurities (cationic impurities and anionic impurities) are removed by adopting a method of acid washing and deionized water washing so as to improve the purity of the electrode material.

However, the method is difficult to effectively remove impurities in the deep complicated pores of the capacitance carbon, and even Cl in acid is introduced in the acid washing process^-、SO₄ ^2-、NO₃ ^-And the content of metal elements or anions in the capacitance carbon material is higher than the national upper limit, so that the capacitance carbon material does not meet the requirement of commercial use. In addition, the method of washing with water (i.e., washing the capacitor carbon with deionized water) also causes a great deal of waste of water resources and increases the cost and the process.

Disclosure of Invention

In view of this, the present invention provides a method for improving the purity of capacitance carbon, and the main purpose of the method is to remove the cation impurities and anion impurities in the capacitance carbon at the same time, so as to improve the purity of the capacitance carbon.

In order to achieve the purpose, the invention mainly provides the following technical scheme:

in one aspect, an embodiment of the present invention provides a method for improving purity of capacitance carbon, including the following steps:

preparing a mixed solution: dispersing capacitance carbon in deionized water to obtain a mixed solution;

impurity removal treatment: adopting amphoteric ion exchange resin particles to carry out impurity removal treatment on the capacitance carbon in the mixed solution, and removing cation impurities and anion impurities in the capacitance carbon to obtain purified capacitance carbon; wherein the ion type of the amphoteric ion exchange resin particles is hydrogen type and hydroxide type.

Preferably, in the step of removing impurities: and removing cation impurities and anion impurities in the capacitance carbon by adopting a static ion exchange mode, which specifically comprises the following steps: adding the amphoteric ion exchange resin particles into the mixed solution, fully mixing for a set time, filtering the amphoteric ion exchange resin particles by using a filter screen, and performing suction filtration on the filtrate; and directly drying the filter cake obtained after the suction filtration treatment to obtain the purified capacitance carbon. Preferably, the particle size of the capacitance carbon is less than or equal to 0.1mm, the particle size of the amphoteric ion exchange resin particles is 0.15-0.8mm, and the mesh number of the filter screen is 20-100 meshes. Preferably, the amphoteric ion exchange resin particles include strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles; wherein the ratio of the strong acidic ion exchange resin particles to the strong basic ion exchange resin particles is (0.85-0.9): 1. preferably, the strongly acidic ion exchange resin particles are hydrogen type ion exchange resin particles, and the strongly basic ion exchange resin particles are hydroxide type ion exchange resin particles; further preferably, the mass ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is (0.5 to 1.5): 2, preferably 1: 2; preferably, the mass ratio of the amphoteric ion exchange resin particles to the capacitance carbon is (0.1-10): 1. Preferably, the fully mixing treatment mode is stirring treatment; wherein the set time is 1-12h, and the stirring speed is 60-180 r/min.

Preferably, in the step of removing impurities: and removing cation impurities and anion impurities in the capacitance carbon by adopting a dynamic ion exchange mode, and specifically comprises the following steps: making the mixed solution flow through an ion exchange column filled with amphoteric ion exchange resin particles to carry out ion exchange treatment, and collecting effluent liquid; and carrying out suction filtration on the effluent liquid, and directly drying a filter cake obtained after the suction filtration treatment to obtain the purified capacitance carbon. Preferably, the particle size of the amphoteric ion exchange resin particles is 0.15-0.8 mm; preferably, the amphoteric ion exchange resin particles include strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles; wherein the ratio of the strong acidic ion exchange resin particles to the strong basic ion exchange resin particles is (0.85-0.9): 1; preferably, in the amphoteric ion exchange resin particles: the particle size of all strong acid ion exchange resin particles is the same, and the particle size of all strong base ion exchange resin particles is the same. Preferably, the strongly acidic ion exchange resin particles are hydrogen type ion exchange resin particles, and the strongly basic ion exchange resin particles are hydroxide type ion exchange resin particles; further preferably, the mass ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is (0.5 to 1.5): 2, preferably 1: 2.

Preferably, the step of preparing the mixed solution is performed at room temperature; and/or in the impurity removing treatment step, the step of ion exchange between the amphoteric ion exchange resin particles and the cation impurities and the anion impurities of the capacitance carbon is carried out at room temperature.

Preferably, after the step of removing impurities, the method further comprises:

a regeneration treatment step: carrying out regeneration treatment on the amphoteric ion exchange resin particles after impurity removal treatment; preferably, the amphoteric ion exchange resin is separated into strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles by using the difference in density, and then subjected to regeneration treatment separately.

Preferably, in the purified capacitance carbon:

the content of Fe element is not more than 50mg/kg, preferably not more than 44.9mg/kg, and further preferably not more than 43.5 mg/kg;

the content of Ni element is not more than 50mg/kg, preferably not more than 2.1mg/kg, and further preferably not more than 1.8 mg/kg;

the content of Co element is not more than 20mg/kg, preferably not more than 0.7mg/kg, and more preferably not more than 0.5 mg/kg;

the content of Cu element is not more than 20mg/kg, preferably not more than 5.4mg/kg, and further preferably not more than 4.9 mg/kg;

the content of Na element is not more than 100mg/kg, preferably not more than 62.7mg/kg, and further preferably not more than 56.1 mg/kg;

the content of K element is not more than 200mg/kg, preferably not more than 64.4mg/kg, and further preferably not more than 58.9 mg/kg;

the content of Al element is not more than 200mg/kg, preferably not more than 98.3mg/kg, and further preferably not more than 85.6 mg/kg;

Cl^-the content is not more than 20mg/kg, preferably not more than 18mg/kg, and further preferably not more than 16 mg/kg;

SO₄ ^2-the content is not more than 10mg/kg, preferably not more than 9mg/kg, and further preferably not more than 8 mg/kg;

NO₃ ^-the content is not more than 10mg/kg, preferably not more than 8mg/kg, and further preferably not more than 6 mg/kg.

Compared with the prior art, the method for improving the purity of the capacitance carbon at least has the following beneficial effects:

the embodiment of the invention provides a method for improving the purity of capacitance carbon, which comprises the steps of dispersing the capacitance carbon in deionized water at room temperature to form a mixed solution, and then removing cation impurities and anion impurities of the capacitance carbon in the mixed solution by adopting amphoteric ion exchange resin particles (the ion types are hydrogen type and hydroxide type). The design can remove various cationic impurities and various anionic impurities simultaneously, can not introduce new impurities, has the advantages of good purification effect, simple operation steps, mild experimental conditions, low cost, environmental friendliness and the like, and is suitable for industrial use.

Further, the embodiment of the present invention provides a method for improving the purity of capacitance carbon, which can remove cationic impurities and anionic impurities in capacitance carbon by using a static ion exchange method, and for this removal method, by designing the particle size distribution of the amphoteric ion exchange resin particles (i.e. setting the particle size ratio of the strong acidic ion exchange resin particles to the strong basic ion exchange resin particles to (0.85-0.9):1), it can be avoided that when the amphoteric ion exchange resin particles are stirred with water, the two resin particles, namely the strong acidic ion exchange resin particles and the strong basic ion exchange resin particles, are layered due to different densities, and thus the final capacitance carbon purity is not uniform.

Further, the embodiment of the invention provides a method for improving the purity of capacitance carbon, which can remove anion impurities and cation impurities in the capacitance carbon by adopting a dynamic ion exchange mode, and the removal mode has high separation efficiency, continuous operation and wide application range. Further, for this removal mode, by setting the particle diameter of the strongly acidic ion exchange particles to a certain particle diameter value of 0.15 to 0.8mm (i.e., all the strongly acidic ion exchange particles are the same in particle diameter), setting the particle diameter of the strongly basic ion exchange particles to another particle diameter value of 0.15 to 0.8mm (i.e., all the strongly basic ion exchange particles are the same in particle diameter), and setting the particle diameter ratio of both the strongly acidic ion exchange resin particles and the strongly basic ion exchange resin particles to (0.85 to 0.9):1, so that the particle diameters of the strong acid ion exchange resin particles and the strong base ion exchange resin particles are respectively uniform, the obtained capacitance carbon is neutral, and the flow rate is improved, so that the exchange system can quickly reach the balance point of pressure difference and purity, and can be used for processing larger flow.

In addition, after the capacitor carbon is purified, the method for improving the capacitor carbon provided by the embodiment of the invention does not need water washing operation, and the capacitor carbon with neutral pH can be obtained by directly drying the filter cake obtained by suction filtration, so that the waste of water resources is avoided, and the working procedures and the cost are further reduced.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram illustrating the removal of anionic and cationic impurities from capacitance carbon using amphoteric ion exchange resin particles as an example of chloride and sodium ions.

Detailed Description

To further explain the technical means and effects of the present invention adopted to achieve the predetermined object, the following detailed description of the embodiments, structures, features and effects according to the present invention will be made with reference to the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "an embodiment" refers to not necessarily the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

Related art regarding purification of capacitance carbon: the traditional technique mainly adopts acid pickling and water addingThe impurities in the capacitance carbon are removed by a washing mode. The latest related art proposes a method for removing metal ions from capacitor carbon by using a strongly acidic cation exchange resin, specifically, capacitor carbon is added to a reaction vessel, hydrochloric acid (hydrochloric acid concentration of 3 to 10%) is added to the reaction vessel, followed by stirring and heating to carry out an acid treatment (heating from room temperature to 105 ℃), then the strongly acidic cation exchange resin is added thereto, followed by stirring to sufficiently exchange with an electrolyte, and then the filter cake is washed with water to have a pH of 6 to 7. However, the inventors of the present invention consider that the latest related art has at least the following problems: (1) due to the hydrochloric acid treatment, anionic impurities (Cl) are introduced^-) Thereby affecting the purity of the capacitance carbon; (2) the impurity removal process is complicated, the reaction conditions are harsh (105 ℃, strong acid), the requirements on equipment performance are high (high temperature resistance and strong acid resistance), and the cost is high; (4) the method needs a water washing step, causes waste of water resources, generates a large amount of waste water and is not environment-friendly.

At present, the related technology does not provide a capacitance carbon purification process which is simple in process, can simultaneously remove cation impurities and anion impurities, has a good purification effect, and is green and environment-friendly.

Based on the defects in the prior art, the invention develops a method for improving the purity of the capacitance carbon with high efficiency, easy operation and low cost to simultaneously remove cations (metal cations: iron, nickel, cobalt, copper, sodium, potassium and aluminum) and anions (Cl) in the capacitance carbon^-、SO₄ ^2-、NO₃ ^-) And reducing the content of impurities to meet the requirements of national standard regulation and commercial use. The method of the present invention includes, but is not limited to, the above-mentioned several impurity ions, for H⁺External cations or OH^-Besides, the removal of anionic impurities has applicability.

The specific scheme of the invention is as follows: the embodiment of the invention provides a method for improving the purity of capacitance carbon, which mainly comprises the following steps:

preparing a mixed solution: and dispersing the capacitance carbon in deionized water at room temperature to obtain a mixed solution.

The method comprises the following steps: mixing the capacitance carbon with deionized water, and stirring to form uniformly dispersed mixed liquid.

In the step, the quality of the capacitance carbon and the deionized water is not particularly required, and a mixed solution can be formed.

Impurity removal treatment: adopting amphoteric ion exchange resin particles to carry out impurity removal treatment on the capacitance carbon in the mixed solution so as to remove cation impurities and anion impurities in the capacitance carbon and obtain purified capacitance carbon; wherein, the ion type of the amphoteric ion exchange resin particles is hydrogen type and oxyhydrogen type.

In this step, the amphoteric ion exchange resin particles include strongly acidic ion exchange resin particles (hydrogen form) and strongly basic ion exchange resin particles (hydrogen-oxygen form). Here, it should be noted that: the relationship between the amounts of strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles is determined by the exchange capacities of the cation exchange resin and the anion exchange resin, the exchange capacity being the number of ions exchangeable per unit mass or unit volume of the functional groups carried by the ion exchange resin, and the amount being inversely proportional to the exchange capacity, the larger the exchange capacity, the smaller the mass used. Preferably, in the present invention, the strongly acidic ion exchange resin (i.e., the strongly acidic ion exchange resin in the hydrogen form) used has an exchange capacity approximately twice that of the strongly basic ion exchange resin (i.e., the strongly basic ion exchange resin in the hydroxide form), and therefore, the mass ratio of the strongly acidic ion exchange resin to the strongly basic ion exchange resin is (0.5 to 1.5): 2, preferably 1: 2.

In this step, the following two schemes can be adopted to implement, specifically as follows:

the first scheme is as follows: and removing the cation impurities and the anion impurities in the capacitance carbon by adopting a static ion exchange mode, which specifically comprises the following steps: adding amphoteric ion exchange resin particles into the mixed solution, fully mixing for a set time (namely fully contacting the amphoteric ion exchange resin particles in a vibration mode, a stirring mode and the like to achieve balance), filtering the amphoteric ion exchange resin particles by using a filter screen, and performing suction filtration on the filtrate; and directly drying the filter cake obtained after the suction filtration treatment to obtain purified capacitance carbon, wherein the pH value of the purified capacitance carbon is neutral.

In the technical scheme, the particle size range of the capacitance carbon is less than or equal to 0.1mm, correspondingly, the particle size range of the amphoteric ion exchange resin particles is 0.15-0.8mm, and the mesh number of the filter screen is 20-100 meshes. Here, the particle size of the amphoteric ion exchange resin particles is larger than that of the capacitance carbon, and the amphoteric ion exchange resin particles and the capacitance carbon are separated by a filter screen using a particle size difference.

Preferably, the particle size distribution of the amphoteric ion exchange resin particles is specially designed so as to avoid the influence on the removal effect caused by layering of strong-acid ion exchange resin particles and strong-base ion exchange resin particles due to different densities when the amphoteric ion exchange resin particles are stirred with deionized water; specifically, the ratio of the particle diameters of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is (0.85-0.9): 1.

Preferably, the mass ratio of the amphoteric ion exchange resin particles to the capacitance carbon is (0.1-10): 1. Through setting up like this, can satisfy the requirement of impurity desorption effect, can not cause the excessive use of resin again, cause the waste.

Preferably, the fully mixing treatment mode is stirring treatment; wherein the set time is 1-12h, and the stirring speed is 60-180 r/min. Here, it should be noted that: if the stirring speed is less than 60 revolutions per minute, the speed is too low, resin particles are layered, so that the anion-cation exchange is asynchronous (part of the capacitance carbon only removes anion impurities, and part of the capacitance carbon only removes cation impurities), and finally, the impurity removal of the capacitance carbon is not thorough, and the purity of the capacitance carbon does not reach the standard; the stirring speed of more than 180 rpm causes the resin particles to be broken, resulting in poor exchange effect and causing the resin fragments and the capacitance carbon to be unable to be separated.

The second scheme is as follows: and removing anion impurities and cation impurities in the capacitance carbon by adopting a dynamic ion exchange mode. The dynamic exchange mode is a separation mode that the mixed solution and the amphoteric ion exchange resin move relatively; the ion exchange mode has high separation efficiency, continuous operation and wide application range. The method comprises the following specific steps:

making the mixed solution flow through an ion exchange column filled with amphoteric ion exchange resin particles to carry out ion exchange treatment, and collecting effluent liquid; and carrying out suction filtration on the effluent, and directly drying a filter cake obtained through the suction filtration to obtain purified capacitance carbon (the pH value of the purified capacitance carbon is neutral). Specifically, particles of the amphoteric ion exchange resin with a specially designed particle size distribution are loaded into an ion exchange column, and the column is tapped to compact the resin and remove air bubbles. The mixed solution is slowly injected into the column and flows through the ion exchange column from top to bottom for ion exchange.

Here, the special design of the particle size distribution means: the particle size of the amphoteric ion exchange resin particles is 0.15-0.8 mm; the particle diameter ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is (0.85-0.9): 1; in the amphoteric ion exchange resin particles: the particle size of all strong acid ion exchange resin particles is the same, and the particle size of all strong base ion exchange resin particles is the same.

That is to say: selecting strong acid ion exchange resin particles with a certain particle size value of 0.15-0.8mm, and selecting strong base ion exchange resin particles with another particle size value according to the particle size ratio of the strong acid ion exchange resin particles to the strong base ion exchange resin particles (0.85-0.9):1, wherein the particle size of the strong base ion exchange resin particles is also between 0.15-0.8 mm.

The particle size distribution is specially designed, so that the particle size of the strong-acid ion exchange resin particles and the particle size of the strong-base ion exchange resin particles are respectively uniform, an exchange system can quickly reach the balance point of pressure difference and purity, the separation time is favorably shortened, and the method can be used for larger treatment flow.

In the above two embodiments, the inventors of the present invention propose the setting of the particle diameter ratio based on the following findings and principles: the upper particle size ratio is dependent on the density ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles. The strongly acidic ion exchange resin particles are in H form, the strongly basic ion exchange resin particles are in OH form, and the strongly acidic ion exchange resin particles and the strongly basic ion exchange resin are in this caseThe particles are held together by the action of positive and negative charges to form countless levels of multiple beds (i.e., yang + yin + … …). The mixed solution passes through the mixed bed resin and is subjected to infinite exchange filtration to obtain a high-purity neutral capacitance carbon aqueous solution. H of strongly acidic ion exchange resin particles⁺Exchange reaction with cation in the mixed solution, exchange OH of resin particles with strong basicity^-H substituted by strongly acidic ion exchange resin particles by a substitution reaction with anions such as sulfate ions and chloride ions in the mixed solution⁺OH displaced from strongly basic ion exchange resin particles^-Ion binding to form H₂And O. If the mixed resin is layered, the above mentioned infinite-stage compound bed does not exist, the strongly basic ion exchange resin particles with light specific gravity are on the upper layer, the strongly acidic ion exchange resin particles with high specific gravity are sunk, and the effluent pH value of the amphoteric ion exchange resin particles is unqualified due to the asynchronism of ion exchange, and finally the pH value of the capacitive carbon is unqualified.

A regeneration treatment step: the amphoteric ion exchange resin particles are separated into strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles by utilizing the difference of density, and then are respectively regenerated.

The scheme of the invention is that amphoteric ion exchange resin is adopted to remove metallic element impurities (mainly comprising iron, nickel, cobalt, copper, sodium, potassium and aluminum) and anion impurities (mainly comprising Cl) in the capacitance carbon^-、SO₄ ^2-、NO₃ ^-) Simply and efficiently removed, thereby preparing the high-purity capacitance carbon which meets the national standard requirements and meets the commercial use. The resin used is an amphoteric ion exchange resin, the ion type is H⁺form/OH^-And (4) molding.

FIG. 1 is a schematic diagram illustrating the removal of cationic and anionic impurities from capacitance carbon using amphoteric ion exchange resin particles as an example of sodium and chloride ions. As shown in fig. 1, the principle of the removal is: the strongly acidic ion exchange resin (containing acidic groups such as sulfonic acid group, carboxyl group, and phenol group, and easily generating H in water) in the amphoteric ion exchange resin particles⁺) On the upper partH of (A) to (B)⁺Ion-exchanging with metal cation impurities to transfer the cation impurities of the capacitance carbon to the strongly acidic ion-exchange resin, and H on the strongly acidic ion-exchange resin⁺Exchange into water. Strongly basic ion exchange resin (containing quaternary amino, imino and other basic groups, easily generating OH in water)^-) OH on^-Can be ion-exchanged with anion impurities, so that the anion impurities of the capacitance carbon are transferred to the strongly basic ion exchange resin, and OH on the strongly basic ion exchange resin^-Exchange into water; exchanged H⁺With OH^-Combine to generate H₂O, and both the cationic and anionic impurities are exchanged onto the amphoteric ion exchange resin. Then, amphoteric ion exchange resin particles are removed from the system by adopting a sieving mode, thereby achieving the purpose of removing impurities.

The removal reaction can be carried out at room temperature and at any pH value, no additional reagent is needed, and the product is only H₂O, so the method has the advantages of mild condition, environmental protection, high efficiency and low cost, and can meet the requirement of industrial use.

The invention is further illustrated below by means of specific examples:

in order to compare the purification effects of the embodiment of the present invention, the following examples and comparative examples are all performed on a plurality of parallel samples of the same capacitance carbon (the embodiment of the present invention is applicable to all types of capacitance carbon purification).

Wherein the particle size of the capacitance carbon is less than or equal to 0.1 mm. Among the amphoteric ion exchange resin particles used in the following examples and comparative examples, strongly acidic ion exchange resin particles are strongly acidic ion exchange resin particles in the hydrogen form, and strongly basic ion exchange resin particles are strongly basic ion exchange resin particles in the hydroxide form.

Example 1

The embodiment provides a method for improving the purity of capacitance carbon, which mainly comprises the following steps:

preparing a mixed solution: at room temperature, 10g of the capacitance carbon sample and 100mL of deionized water are placed in a beaker and stirred to form a uniformly dispersed mixed solution.

Impurity removal treatment: adding 10g of amphoteric ion exchange resin particles into the mixed solution, continuously stirring for 3h (wherein the stirring speed is 100 revolutions per minute), filtering the amphoteric ion exchange resin particles by using a filter screen, carrying out suction filtration on the filtrate, and directly drying the obtained filter cake to obtain the purified capacitance carbon. In this embodiment, the pH value of the capacitor carbon obtained after purification is neutral.

Wherein, in this step, the particle diameter of the strongly acidic ion exchange resin particles is 0.15mm, and the particle diameter of the strongly basic ion exchange resin particles is 0.18mm, (wherein, the particle diameter ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is 0.85: 1). The mass ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is 1: 2; the mesh number of the used filter screen is 100 meshes.

A regeneration treatment step: the filtered amphoteric ion exchange resin particles are separated into strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles by using the difference of density, and then are regenerated respectively.

Example 2

The present embodiment provides a method for improving the purity of capacitance carbon, and the main difference between the present embodiment and embodiment 1 is: the particle size of the strongly acidic ion exchange resin particles and the particle size of the strongly basic ion exchange resin particles in the amphoteric ion exchange resin particles selected in the impurity removal treatment step are 0.4mm and 0.44mm (wherein the particle size ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is 0.9: 1).

Other steps and parameters are completely consistent.

In this embodiment, the pH value of the capacitor carbon obtained after purification is neutral.

Example 3

The present embodiment provides a method for improving the purity of capacitance carbon, and the main difference between the present embodiment and embodiment 1 is: in the impurity removal treatment step, 1g of amphoteric ion exchange resin particles are added into the mixed solution in the step 1) and stirred for 12 hours. Other steps and parameters are completely consistent.

In this embodiment, the pH value of the capacitor carbon obtained after purification is neutral.

Example 4

The present embodiment provides a method for improving the purity of capacitance carbon, and the main difference between the present embodiment and embodiment 1 is: in the impurity removal treatment step, 100g of amphoteric ion exchange resin particles are added into the mixed solution in the step 1) and stirred for 1 h. Other steps and parameters are completely consistent.

In this embodiment, the pH value of the capacitor carbon obtained after purification is neutral.

Example 5

The embodiment provides a method for improving the purity of capacitance carbon, which mainly comprises the following steps:

preparing a mixed solution: at room temperature, 10g of the capacitance carbon sample and 100mL of deionized water are placed in a beaker and stirred to form a uniformly dispersed mixed solution.

Impurity removal treatment: at room temperature, 10g of amphoteric ion exchange resin particles (wherein the mass ratio of strongly acidic ion exchange resin particles to strongly basic ion exchange resin particles is 1:2, the particle size of strongly acidic ion exchange resin particles is 0.5mm, and the particle size of strongly basic ion exchange resin particles is 0.56 mm; that is, the particle size ratio of strongly acidic ion exchange resin particles to strongly basic ion exchange resin particles is 0.89:1) were charged into an ion exchange column, and the column was tapped to compact the amphoteric ion exchange resin particles and remove air bubbles.

And slowly injecting the mixed solution into an ion exchange column, performing ion exchange with amphoteric ion exchange resin particles from top to bottom through the ion exchange column, collecting effluent liquid, performing suction filtration, and directly drying a filter cake obtained through the suction filtration to obtain the purified capacitance carbon. In this embodiment, the pH value of the capacitor carbon obtained after purification is neutral.

Here, the time for the mixed solution to flow through the ion exchange column was 5 hours.

A regeneration treatment step: the amphoteric ion exchange resin particles are separated into strongly acidic ion exchange resin particles and strongly basic ion exchange resin particles by utilizing the difference of density, and then are respectively regenerated.

Example 6

This example provides a method for improving the purity of capacitance carbon, and the difference between this example and example 5 is that: among the amphoteric ion exchange resin particles used in this example: the particle size of the strong acid ion exchange resin particles is 0.15mm, and the particle size of the strong base ion exchange resin particles is 0.17 mm; wherein the ratio of the strong acidic ion exchange resin particles to the strong basic ion exchange resin particles is 0.88: 1. Wherein the time of the mixed solution flowing through the ion exchange column is 12 h.

Other steps and parameters are completely consistent.

In this embodiment, the pH value of the capacitor carbon obtained after purification is neutral.

Example 7

This example provides a method for improving the purity of capacitance carbon, and the difference between this example and example 5 is that: among the amphoteric ion exchange resin particles used in this example: the particle size of the strongly acidic ion exchange resin particles is 0.68 mm, and the particle size of the strongly basic ion exchange resin particles is 0.8 mm; wherein the ratio of the strong acidic ion exchange resin particles to the strong basic ion exchange resin particles is 0.85: 1. Wherein the time of the mixed solution flowing through the ion exchange column is 1 h.

Other steps and parameters are completely consistent.

In this embodiment, the pH value of the capacitor carbon obtained after purification is neutral.

Comparative example 1

Comparative example 1 is a control experiment for example 1, the specific procedure is as follows:

at room temperature, 10g of capacitance carbon sample and 100mL of deionized water are placed in a beaker and stirred to form a uniformly dispersed mixed solution, the mixed solution is continuously stirred for 3 hours and then is filtered (wherein the stirring speed is 100 revolutions per minute), and a filter cake is dried to obtain a control sample which is not treated by the amphoteric ion exchange resin.

Comparative example 2

Comparative example 2 provides a method for improving the purity of capacitance carbon, and the main difference between comparative example 2 and example 1 is that:

the particle size of the strongly acidic ion exchange resin particles and the particle size of the strongly basic ion exchange resin particles in the amphoteric ion exchange resin particles selected in the impurity removal treatment step are respectively 0.15mm and 0.15mm (wherein the particle size ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is 1: 1).

After stirring for 3 hours, the amphoteric ion exchange resin particles show obvious layering phenomenon (strong acid ion exchange resin particles sink and strong base ion exchange resin particles float), so that the cation-anion exchange is insufficient, and the purified capacitance carbon has uneven purity and unqualified pH.

Other steps and parameters are completely consistent.

Comparative example 3

Comparative example 3 provides a method for improving the purity of capacitance carbon, and the main difference between comparative example 3 and example 1 is that:

the strongly acidic ion exchange resin particles and the strongly basic ion exchange resin particles in the amphoteric ion exchange resin particles selected in the impurity removal treatment step have a particle size of 0.15mm and a particle size of 0.21mm (wherein the particle size ratio of the strongly acidic ion exchange resin particles to the strongly basic ion exchange resin particles is about 0.7: 1).

After stirring for 3h, the amphoteric ion exchange resin particles show obvious layering phenomenon (the strong-acid ion exchange resin particles float upwards, and the strong-base ion exchange resin particles sink), so that the cation-anion exchange is insufficient, and the purified capacitance carbon has uneven purity and unqualified pH.

Other steps and parameters are completely consistent.

Comparative example 4

Comparative example 4 provides a method of increasing the purity of capacitance carbon, and comparative example 4 differs from example 5 in that:

the amphoteric ion exchange resin particles used in comparative example 4 are different in particle size among all strong-acid ion exchange resin particles, specifically, various particle size values between 0.15 and 0.8 mm; the particle size of the strongly basic ion exchange resin particles is different, specifically, the particle size is distributed in a plurality of particle size values between 0.15mm and 0.8mm, wherein the time for the mixed solution to flow through the ion exchange column is 23 h. Other steps and parameters are completely consistent.

The purified capacitor carbons obtained in examples 1 to 7 and comparative example 1 were measured for impurities and contents thereof, and the results are shown in table 1.

TABLE 1 impurity content of purified capacitor carbon

From the data above for examples 1-7, comparative examples 1-4, and Table 1, it can be seen that:

(1) the scheme for simultaneously removing the cationic impurities and the anionic impurities on the capacitance carbon by adopting the amphoteric ion exchange resin particles provided by the embodiment of the invention has the following advantages: the method has the advantages of remarkable purification effect, simple operation steps, mild experimental conditions, low cost and environmental friendliness, and is suitable for industrial use.

(2) When the static ion exchange mode is adopted to remove the cation impurities and the anion impurities in the capacitance carbon, the particle diameter ratio of the strong acid ion exchange resin particles to the strong base ion exchange resin particles is set to be (0.85-0.9):1, so that the purification effect of the capacitance carbon can be further improved.

(3) When cation impurities and anion impurities in the capacitance carbon are removed by adopting a dynamic ion exchange mode, the particle diameters of all strong acid ion exchange resin particles are the same and are a certain particle diameter value between 0.15 and 0.8mm, the particle diameters of all strong base ion exchange resin particles are the same and are another particle diameter value between 0.15 and 0.8mm, and the particle diameter ratio of the strong acid ion exchange resin particles to the strong base ion exchange resin particles is (0.85-0.9): 1; the above arrangement not only makes the purification effect of the ion dynamic mode good, but also improves the water outlet rate, so that the exchange system can quickly reach the balance point of pressure difference and purity, and can be used for larger treatment flow.

In addition, the electrochemical performance test is carried out on the purified capacitance carbon of the embodiment and the comparative example, and the test result shows that: the capacitance carbon purified by the embodiment of the invention has excellent cycle stability.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and any simple modification, equivalent change and modification made to the above embodiment according to the technical spirit of the present invention are still within the scope of the technical solution of the present invention.