WO2016058230A1

WO2016058230A1 - Purification method and system for three-dimensional graphene-covered single-particle nanodiamonds

Info

Publication number: WO2016058230A1
Application number: PCT/CN2014/090363
Authority: WO
Inventors: 彭雁; 杜桂香
Original assignee: 彭碳科技有限公司
Priority date: 2014-10-13
Filing date: 2014-11-05
Publication date: 2016-04-21
Also published as: CN105502332B; CN105502332A

Abstract

A purification method and system for three-dimensional graphene-covered single-particle nanodimonds. A prepared mixture of the three-dimensional graphene-covered single-particle nanodimonds is purified. By means of optimal design of the prior art, the mixture undergoes successive processes of separation by excitation, acidification, oxidation, alkalization, and dense media separation, thus allowing removal of impurities such as metal impurities or metal ions, silicon, and amorphous carbon from a mixed solution, and achieving the goal of purification. Furthermore, the entire purification process can be carried out at room temperature and room pressure by employing a solution having less acidity or alkalinity, thus avoiding a large number of repeated processes, simplifying process steps, reducing process time, solving the existing problem of reduced equipment service life caused by repeated oscillating reactions with strong acids and strong alkalis at high-temperature and high-pressure environments, extending the equipment service life, and saving costs.

Description

Method and system for purifying three-dimensional graphene coated single-particle nano diamond

Technical field

The invention relates to the technical field of chemical processes, in particular to a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material and a purification process system thereof.

Background technique

Graphene is a hexagonal lattice honeycomb two-dimensional structure composed of a single layer of SP ² hybridized carbon atoms. It has stable structure, excellent electrical and thermal conductivity and good mechanical properties, and has been extensively studied. Graphene has been prepared and used in energy storage, transparent electrodes, mechanical drives and the like. In order to further develop the potential applications of graphene, especially in energy storage conversion, in addition to two-dimensional graphene films, three-dimensional graphene structures have also been able to be prepared, and in recent years, three-dimensional graphene coated oxides, carbon materials, etc. Materials have been extensively studied. For example, three-dimensional graphene-coated single-particle nano-diamond materials, due to the coating of three-dimensional graphene, significantly improve the electrical conductivity of the coated nano-diamond material, and combine the excellent properties of graphene. These composites have significantly improved electrical conductivity and excellent performance in catalysis, capacitors, and energy storage, and have become one of the international frontiers and hotspots in the field of physical and semiconductor electronics research.

Generally, a three-dimensional graphene-coated single-particle nano-diamond material is prepared by a thermal expansion method or the like, and the products prepared by these methods have other impurities besides the material, for example, amorphous carbon, residual metal impurities or metal ions, Silicon impurities and the like, therefore, it is necessary to purify the mixture containing the above material, and extract the three-dimensional graphene-coated single-particle nano-diamond material.

The existing method for purifying a three-dimensional graphene-coated single-particle nano-diamond material comprises high-temperature and high-pressure conditions, and is purified by intermittent shaking with a strong acid and a strong alkali, for example, by using a mixed solution of nitric acid or sulfuric acid, and hydrogen peroxide or aqua regia. Separate and filter by shaking to achieve purification. However, the above method has a low purification rate, and even requires a large amount of repeated filtration, which increases the production time, thereby reducing the production efficiency and increasing the production cost; and, using a strong acid or a strong base, is highly corrosive to the purified equipment. Will shorten the service life of the equipment and further increase production costs.

Summary of the invention

In order to overcome the above problems, the present invention aims to provide a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material and a purification process system thereof, and has achieved the purpose of improving the purification rate.

In order to achieve the above object, the technical solution of the present invention is as follows:

The invention provides a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material, and purifying a mixture containing a three-dimensional graphene-coated single-particle nano-diamond material, which comprises the following steps:

Step 01: performing a magnetic separation process on the mixture;

Step 02: performing an acidification process on the mixture obtained in step 01;

Step 03: performing an oxidation process on the mixture obtained in step 02;

Step 04: performing an alkalization process on the mixture obtained in step 03;

Step 05: The mixture obtained in the step 04 is subjected to a heavy liquid separation process.

Preferably, the step 04 and the step 05 further comprise: performing a re-acidification process on the mixture obtained in the step 04.

Preferably, in the step 02, the acidification process specifically includes:

Step 011: placing the mixture subjected to the magnetic separation process in an acidic solution of an acidification apparatus;

Step 012: acidifying the mixture under normal temperature and pressure;

Step 013: After a certain acidification time, the acidified mixed solution is placed in a filtering device;

Step 014: Filtering and washing the mixed solution with purified water and a filtering device to remove trace metal particle impurities in the mixture.

Preferably, in the step 03, the oxidation process specifically includes:

Step 021: placing the mixture after the acidification process in an oxidizing solution of an oxidation device;

Step 022: performing oxidation treatment on the mixture under normal temperature and normal pressure;

Step 023: After a certain oxidation time, the oxidized mixed solution is placed in a filtering device;

Step 024: Filtering and washing the mixed solution with purified water and a filtering device to remove amorphous carbon in the mixture.

Preferably, in the step 04, the alkalization process specifically includes:

Step 031: placing the mixture of the oxidation process in the alkalization apparatus;

Step 032: alkalizing the mixture with an alkaline solution under normal temperature and pressure;

Step 033: After a certain alkalization time, the alkalized mixed solution is placed in a filtering device;

Step 034: The mixed solution is subjected to filtration cleaning using purified water and a filtration device to remove silicon in the mixture.

Preferably, the re-acidification process specifically comprises:

Step 151: placing the mixture after the alkalization process in a dilute hydrochloric acid solution of an acidification device;

Step 152: performing re-acidification treatment on the mixture under normal temperature and pressure;

Step 153: After a certain re-acidification time, the re-acidified mixed solution is placed in a filtering device;

Step 154: Filtering and washing the mixed solution with purified water and a filtering device to remove metal ion impurities in the mixture.

Preferably, the acidification process employs a weak acid solution; the alkalization process employs a weak base solution.

Preferably, in the step 05, the heavy liquid separation process is a centrifugation process.

The invention also provides a purification process system for a three-dimensional graphene-coated single-particle nano-diamond material, which comprises purifying a mixture containing a three-dimensional graphene-coated single-particle nano-diamond material, which comprises:

a magnetic separation device that performs a magnetic separation process on the mixture;

An acidification unit comprising an acidification reaction device and an acidification filtration device; the acidification device performs an acidification process on the mixture from the magnetic separation device; and the acidification filtration device filters and washes the mixed solution obtained after the acidification process;

An oxidation unit comprising an oxidation reaction device and an oxidation filtration device; the oxidation device performing an oxidation process on the mixture coming out of the acidification unit; and the oxidation filtration device filtering and cleaning the mixed solution obtained after the oxidation process;

An alkalization unit comprising an alkalization reaction device and an alkalization filter device; the alkalization device performs an alkalization process on the mixture from the oxidation unit; the alkalized filter device is obtained after the alkalization process Mixing solution for filtration cleaning;

a heavy liquid separation unit comprising a heavy liquid separation device that performs a heavy liquid separation process on a mixture coming out of the oxidation unit; and an extraction device that passes the three-dimensional graphite through the heavy liquid separation process The olefin coated single-particle nano-diamond material is extracted.

Preferably, in the purification process system, the acidifying unit comprises a first acidifying unit and a second acidifying unit;

The first acidification unit includes a first acidification reaction device and a first acidification filtration device; the first acidification device performs a first acidification process on the mixture from the magnetic separation device; the first acidification filtration device pair The mixed solution obtained after the first acidification process is subjected to filtration cleaning;

The second acidification unit includes a second acidification reaction device and a second acidification filtration device; the second acidification device performs a second acidification process on the mixture from the alkalization unit; the second acidification filtration device is subjected to the second acidification process The resulting mixed solution was subjected to filtration washing.

Purification method and purification process of three-dimensional graphene coated single-particle nano diamond material of the invention The purification process is optimized, and the mixture is subjected to magnetic separation, acidification, oxidation, alkalization and heavy liquid separation processes in sequence, thereby removing metal impurities or metal ions, silicon and amorphous carbon impurities in the mixture. The purpose of purification is to significantly increase the purification rate while avoiding a large number of repeated separations resulting in an increase in production cost; and further, the entire purification process can be carried out under normal temperature and normal pressure conditions, using weak acid, weak base or acid or alkaline. The small solution is separately acidified and alkalized, which simplifies the process steps and shortens the process time, thereby avoiding the problem of shortening the life of the equipment caused by the existing strong acid, alkali and high temperature and high pressure environment, and less corrosion damage to the equipment. The service life of the equipment saves costs.

DRAWINGS

1 is a block diagram of a purification process system in accordance with a preferred embodiment of the present invention

2 is a block diagram of a purification process system in accordance with a preferred embodiment of the present invention.

3 is a schematic flow chart of a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to Embodiment 1 of the present invention;

4 is a diagram showing the relationship between a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to Embodiment 1 of the present invention;

5 is a schematic flow chart of an acidification process in a process of purifying a three-dimensional graphene-coated single-particle nano-diamond material according to a preferred embodiment of the present invention;

Figure 6 is a diagram showing the relationship of the acidification process of a preferred embodiment of the present invention.

7 is a flow chart showing the oxidation process in the purification process of a three-dimensional graphene-coated single-particle nano-diamond material according to a preferred embodiment of the present invention.

Figure 8 is a diagram showing the relationship of the oxidation process of a preferred embodiment of the present invention.

FIG. 9 is a flow chart showing the alkalization process in the purification process of a three-dimensional graphene-coated single-particle nano-diamond material according to a preferred embodiment of the present invention.

Figure 10 is a diagram showing the relationship of the alkalization process of a preferred embodiment of the present invention.

11 is a schematic flow chart of a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to a second embodiment of the present invention;

12 is a flow chart showing the re-acidification process in the purification process of a three-dimensional graphene-coated single-particle nano-diamond material according to a preferred embodiment of the present invention.

Figure 13 is a diagram showing the relationship of the apparatus for the re-acidification process according to a preferred embodiment of the present invention.

detailed description

In order to make the content of the present invention clearer and easier to understand, the contents of the present invention will be further described below in conjunction with the accompanying drawings. Of course, the invention is not limited to the specific embodiment, and general replacements well known to those skilled in the art are also encompassed within the scope of the invention.

As mentioned above, the existing purification method requires intermittent shaking separation using strong acid and strong alkali under high temperature and high pressure conditions, which not only severely corrodes equipment, shortens equipment life, increases process time and increases process cost, but also has no purification effect. Ideally, it requires a large number of repeated separations, which further increases the production cost. To this end, the present invention proposes a purification method of three-dimensional graphene-coated single-particle nano-diamond material, which optimizes the purification process and sequentially subjects the mixture to magnetic separation. , acidification, oxidation, alkalization and heavy liquid separation process, while avoiding a large number of repeated separations resulting in an increase in production costs, significantly improving the purification rate; and further the entire purification process can be carried out under normal temperature and pressure conditions, using weak acid The weak alkali or the acidic and alkaline solution are respectively subjected to the acidification and alkalization process, thereby avoiding the problem that the existing strong acid, alkali and high temperature and high pressure environment cause the shortening of the equipment life, and the corrosion damage to the equipment is small and prolonged. The service life of the equipment saves costs.

In the present invention, the preparation process of the three-dimensional graphene-coated single-particle nano-diamond material may specifically include:

Step L1: design formula; the formula includes the ratio of various raw materials. In this embodiment, the formula consists of the following raw materials: trinitrotoluene; black gold/oktokin; metal. The ratio of each raw material can be set according to the actual process needs. For example, a weight percentage of 20 trinitrotoluene; a weight percentage of 60% black gold, and 20% metal.

Step L2: preparing an energetic material according to the formula;

Specifically, each raw material in the formulation can be uniformly mixed and then press-formed, that is, an energetic material. The shape of the energetic material may be consistent with the shape of the reaction chamber. For example, if the reaction chamber is spherical, the energetic material may be pressed into a spherical shape, and the density of the spherical energetic material may be greater than 1.8 T/M ² ; the shape of the shaped energetic material The ratio to the shape of the reaction chamber may be 1: (50-100). It should be noted here that the energetic material may be an explosive, an ignition powder, a primer, or the like.

Step L3: loading the energetic material into the reaction chamber;

Specifically, the energetic material may be immersed in an aqueous container, and then the aqueous container is suspended in the reaction chamber;

Step L4: triggering the energetic material to synthesize a mixture containing the three-dimensional graphene-coated single-particle nano-diamond material;

Specifically, there are many ways to trigger energetic materials, such as detonator triggering. The high energy generated by the energetic material causes the free carbon to react to form a three-dimensional graphene-coated single-particle nano-diamond material; at the same time, impurities such as amorphous carbon, silicon, metal particles and the like are inevitably generated, so that the product contains three-dimensional stones. A mixture of icosene coated single-particle nano-diamond material; the mixture needs to be purified to obtain a three-dimensional graphene-coated single-particle nano-diamond material having a higher purity.

It should be noted that the three-dimensional graphene-coated single-particle nano-diamond material in the present invention can also adopt the existing method, which is known to those skilled in the art, and the present invention will not be described again.

In the present invention, a method for purifying a prepared mixture containing a three-dimensional graphene-coated single-particle nano-diamond material, and a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material comprises the following steps:

Step 01: performing a magnetic separation process on the mixture;

Step 03: performing an oxidation process on the mixture obtained in step 02;

Step 04: performing an alkalization process on the mixture obtained in step 03;

The invention also provides a purification process system for a three-dimensional graphene-coated single-particle nano-diamond material, which comprises purifying a mixture of the prepared three-dimensional graphene-coated single-particle nano-diamond material, which comprises: a magnetic separation device for performing a magnetic separation process, an acidification unit for performing an acidification process, an oxidation unit for performing an oxidation process, an alkalization unit for performing an alkalization process, and a heavy liquid separation unit;

An acidification unit comprising an acidification reaction device and an acidification filtration device; the acidification device performs an acidification process on the mixture from the magnetic separation device or the alkalization unit, for example, an acid-resistant reaction kettle; and a mixed solution obtained by the acidification filtration device after the acidification process Performing a filter cleaning, for example, may be a porous ceramic membrane;

An oxidation unit comprising an oxidation reaction device and an oxidation filtration device; the oxidation device performs an oxidation process on the mixture from the acidification unit, for example, may be a corrosion resistant reaction kettle; and the oxidation filtration device filters and cleans the mixed solution obtained after the oxidation process. For example, it may be a porous ceramic membrane;

An alkalization unit comprising an alkalization reaction device and an alkalization filter device; the alkalization device performs an alkalization process on the mixture from the oxidation unit, for example, may be an alkali-resistant reaction kettle; and the alkalization filtration device is subjected to the alkalization process The mixed solution obtained after that is subjected to filtration cleaning, for example, may be a porous ceramic membrane;

a heavy liquid separation unit comprising a heavy liquid separation device and an extraction device, wherein the heavy liquid separation device performs a heavy liquid separation process on the mixture from the oxidation unit or the acidification unit, for example, may be a high speed centrifuge, etc.; the extraction device separates the heavy liquid The process of extracting three-dimensional graphene-coated single-particle nanodiamond materials.

It should be noted that the purification process system of the present invention may further comprise an automatic control device for automatically controlling the respective units; and a water supply system for supplying purified water to the respective units; and may further include a product collection container or the like. Any magnetic separation process, acidification process, oxidation process, alkali The chemical conversion process, the apparatus for the heavy liquid separation process, and the equipment for filtration cleaning can be applied to the present invention.

1 is a block diagram of a purification process system in accordance with a preferred embodiment of the present invention; the purification process system in one embodiment of the present invention includes:

The acidification unit comprises an acidification reaction device and an acidification filtration device; the acidification device performs an acidification process on the mixture from the magnetic separation device; and the acidification filtration device filters and washes the mixed solution obtained after the acidification process;

An oxidation unit comprising an oxidation reaction device and an oxidation filtration device;

An alkalizing unit comprising an alkalizing reaction device and an alkalizing filter device;

a heavy liquid separation unit comprising a heavy liquid separation device and an extraction device, the heavy liquid separation device performing a heavy liquid separation process on the mixture coming out of the oxidation unit; the extraction device is a three-dimensional graphene-coated single-particle nano-diamond material subjected to a heavy liquid separation process Extract it out.

2 is a block diagram of a purification process system according to a preferred embodiment of the present invention; the purification process system in another embodiment of the present invention includes:

The acidifying unit includes a first acidifying unit and a second acidifying unit;

a first acidification unit comprising a first acidification reaction device and a first acidification filtration device; the first acidification device performs a first acidification process on the mixture from the magnetic separation device; the first acidification filtration device is obtained after the first acidification process Mixing solution for filtration cleaning;

The second acidification unit includes a second acidification reaction device and a second acidification filtration device; the second acidification device performs a second acidification process on the mixture from the alkalization unit; and the second acidification filtration device filters and washes the mixed solution obtained after the second acidification process.

a heavy liquid separation unit comprising a heavy liquid separation device and an extraction device, the heavy liquid separation device performing a heavy liquid separation process on the mixture from the second acid oxidation unit; the extraction device is a three-dimensional graphene coated single particle subjected to the heavy liquid separation process The nanodiamond material is extracted.

The method for purifying the three-dimensional graphene-coated single-particle nano-diamond material of the present invention will be further described in detail below with reference to FIGS. 3-13 and specific examples. It should be noted that the drawings are in a very simplified form, using a non-precise ratio, and are only used to facilitate the purpose of the present embodiment.

Embodiment 1

Please refer to FIG. 3 and FIG. 4 , wherein FIG. 3 is a schematic flow chart of a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to Embodiment 1 of the present invention; FIG. 4 is a three-dimensional graphene according to Embodiment 1 of the present invention; Equipment relationship diagram for the purification method of coated single-particle nano-diamond material.

In this embodiment, the mixture prepared by the above-mentioned three-dimensional graphene-coated single-particle nano-diamond material is purified, and the mixture includes metal particle impurities or metal ion impurities, amorphous carbon, silicon and the like; In the purification method of the three-dimensional graphene-coated single-particle nano-diamond material, the whole purification process can be carried out under normal temperature and pressure, and the following steps are included:

Step 01: performing a magnetic separation process on the mixture;

Specifically, as shown by the broken line frame I in FIG. 4, the magnetic separation process may employ a magnetic separation device a and an automatic control device, and the magnetic separation process may initially remove bulk metal impurities in the mixture. The principle of magnetic separation is a technology in the field. As will be apparent to those skilled in the art, the present invention will not be described again. After the magnetic separation process, the bulk metal impurities in the mixture are removed, and then the mixture proceeds to the next step 02;

Specifically, as shown by the broken line frame II in FIG. 4, the acidification process can be carried out under normal temperature and normal pressure, and the mixture is placed in an acidic solution, and the acidic reactant used may be a weak acid or a diluted strong acid, which is Because the corrosion of the diluted strong acid is relatively reduced, the corrosion damage to the acidic equipment is minimized. The acidification process is carried out in the acidification reaction chamber b of the acidification device, which can remove the metal particle impurities in the mixture, including removing trace metal elements; this is because the acidic solution can undergo displacement reaction with the metal particle impurities during the acidification process, The metal particle impurities are converted into a chloride solution, and are no longer solid, facilitating separation from the solid three-dimensional graphene-coated single-particle nano-diamond material; in this embodiment, after the acidification process, the method further comprises: after acidification The resulting mixed solution was subjected to filtration washing. The mixed solution can be filtered and washed with a ceramic membrane c and purified water to remove metal particle impurities.

Please refer to FIG. 5 and FIG. 6. FIG. 5 is a schematic flow chart of an acidification process in a process for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to a preferred embodiment of the present invention; FIG. 6 is a preferred embodiment of the present invention. An equipment relationship diagram of the acidification process of the examples. The acidification process in the preferred embodiment may specifically include the following steps:

Step 021: The mixture after the magnetic separation process is placed in the acidic solution in the acidification device 1a;

Specifically, after the magnetic separation of the mixture, the bulk metal has been eliminated, and thereafter, the mixture is placed in an acidic solution, which may be a weak acid or a diluted strong acid solution, such as diluted hydrochloric acid, sulfurous acid, carbonic acid, hypochlorous acid, Hydrogen sulfuric acid, etc.;

Step 022: acidifying the mixture under normal temperature and pressure;

Specifically, at normal temperature and pressure, as shown in FIG. 6, the acidification treatment is carried out in the acidification reaction chamber of the acidification apparatus 1a, and the acidic solution used is dilute hydrochloric acid, and the concentration of the diluted hydrochloric acid may be less than 25%. Further, Can be 5-25%. Here, the acidification equipment may be an acid resistant reactor, used in conjunction with a conductivity meter.

Step 023: After a certain acidification time, the acidified mixed solution is placed in the filtration device 1b; here, the acidification time may be 1-5 hours.

Step 024: Filtering and washing the mixed solution with pure water and a filtering device 1b to remove trace metal particle impurities in the mixture.

Specifically, the filtering device 1b may be a ceramic membrane, so that the mixed solution may be filtered and washed with a ceramic membrane and purified water to remove metal particle impurities. Here, the pore size of the filter pore of the ceramic membrane may be 10-200 nm, the conductivity of the purified water may be less than 5 μs, and the pH of the mixed solution to be washed is between 3-9; a self-control device may be used to control the process. The invention is not limited thereto. The filtering and cleaning process comprises: adding purified water to the filtering device 1b to repeatedly filter and wash the mixed solution until the pH of the mixed solution is between 3 and 9 to complete the filtering and cleaning.

The acidification process can remove the metal particle impurities in the mixture, including removing trace metal elements, such as Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu or Zn; this is due to the acid solution during the acidification process. It can be replaced with metal particle impurities, and the metal particle impurities can be converted into a chloride solution instead of being solid. It is easy to filter and separate with the solid three-dimensional graphene-coated single-particle nano-diamond.

Step 03: performing an oxidation process on the mixture obtained in step 02;

Specifically, as shown by the broken line frame III in FIG. 4, the oxidation process can be carried out under normal temperature and normal pressure conditions, and the mixture is placed in an oxidizing solution, and the oxidizing solution used may be sulfuric acid, potassium permanganate or hydrogen peroxide. The oxidation-reduction reaction is carried out; the oxidation process is carried out in the oxidation reaction chamber d of the oxidation apparatus, which can remove the amorphous carbon in the mixture. The reaction principle is that the oxidation reactant in the solution can oxidize the amorphous carbon to CO ₂ gas and discharge it. In this embodiment, after the oxidation process, the mixed solution obtained after the oxidation is further subjected to filtration cleaning; the filtration device used for the filtration cleaning may be a ceramic membrane e, and pure water is used, thereby obtaining a mixture after removing the amorphous carbon.

Please refer to FIG. 7 and FIG. 8. FIG. 7 is a schematic flow chart of an oxidation process in the process of purifying three-dimensional graphene-coated single-particle nano-diamond according to a preferred embodiment of the present invention; FIG. 8 is a preferred embodiment of the present invention. Device diagram of the oxidation process. The oxidation process of the preferred embodiment specifically includes the following steps:

Step 031: placing the mixture after the acidification process in an oxidizing solution in the oxidation device 2a;

Specifically, the mixture is placed in an oxidizing solution, and a weak acid solution may be used. For example, the oxidizing solution includes: sulfuric acid having a concentration of less than 30%, potassium permanganate having a concentration of less than 30%, and hydrogen peroxide having a concentration of less than 40%.

As shown in Fig. 8, there are two oxidation reaction apparatuses 2a, but the number of oxidation apparatuses 2a is not limited in the present invention.

Step 032: oxidizing the mixture under normal temperature and pressure;

Specifically, under normal temperature and normal pressure, as shown in Fig. 8, the oxidation treatment is carried out in the oxidation reaction chamber of the oxidation device 2a. Here, the oxidation device 2a may be an acid-resistant reaction vessel and used together with a conductivity meter.

Step 033: After a certain oxidation time, the oxidized mixed solution is placed in the filtration device 2b; here, the oxidation time may be 1-5 hours.

Step 034: Filtering and washing the mixed solution with purified water and a filtering device 2b to remove the amorphous carbon in the mixture.

Specifically, the filtering device 2b may be a ceramic membrane, so that the mixed solution may be filtered and washed with a ceramic membrane and purified water to remove the amorphous carbon. Here, the pore size of the filter pore of the ceramic membrane may be 10-200 nm, the conductivity of the purified water may be less than 5 μs, and the pH of the mixed solution to be washed is between 3-9; a self-control device may be used to control the process. The invention is not limited thereto. The filtering and cleaning process comprises: adding purified water to the filtering device to repeatedly filter and wash the mixed solution until the pH of the mixed solution is between 3 and 9 to complete the filtering and cleaning.

The oxidation process can remove the amorphous carbon in the mixture; this is due to the formation of some amorphous carbon in the process of preparing the three-dimensional graphene-coated single-particle nano-diamond, which needs to be removed; using an oxidizing solution, it can be The shaped carbon is oxidized to form a CO ₂ gas and is discharged from the mixed solution to be separated from the solid three-dimensional graphene-coated single-particle nano-diamond.

Step 04: performing an alkalization process on the mixture obtained in step 03;

Specifically, as shown by the broken line frame IV in FIG. 4, the alkalization process can be carried out under normal temperature and normal pressure conditions, and the mixture is placed in an alkaline solution, and the alkaline reactant can be a diluted strong alkali solution. It may be a weak base solution which is carried out in the alkalization reaction chamber f of the alkalizing apparatus, which can remove silicon impurities in the mixture. The reaction principle is that the basic reactant reacts with silicon impurities to form a silicate and dissolves in an alkaline solution, thereby changing the silicon impurity from a solid to a liquid. In this embodiment, after the alkalization process, the mixed solution obtained after alkalization is further filtered and cleaned; the filtering device used for the filter cleaning may be a ceramic film g, and pure water is used to obtain a mixture after removing silicon impurities. .

Please refer to FIG. 9 and FIG. 10. FIG. 9 is a schematic flow chart of an alkalization process in a process for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to a preferred embodiment of the present invention; FIG. A device diagram of the alkalization process of the preferred embodiment. The alkalization process of the preferred embodiment specifically includes the following steps:

Step 041: placing the mixture of the oxidation process in the alkalizing device 3a;

Specifically, after the oxidation process, impurities such as silicon remain in the mixture, and therefore, the oxidation process mainly removes silicon impurities. As shown in Fig. 10, there are two alkalizing reaction apparatuses 3a, but the number of alkalizing apparatuses 3a is not limited in the present invention.

Step 042: alkalizing the mixture with an alkaline solution at normal temperature and pressure;

Specifically, the mixture is placed in an alkaline solution at normal temperature and pressure, and the alkaline reactant may be a diluted strong alkali solution or a weak base solution, for example, NH ₃ ·H ₂ O, or the like, or Diluted sodium hydroxide; as shown in Fig. 10, the alkalization process is carried out in the alkalization reaction chamber of the alkalizing apparatus 3a, and sodium hydroxide having a concentration of less than 40% can be used. For example, the concentration of sodium hydroxide is 5- 40%, under normal temperature and pressure conditions, the alkalization time is 1-5 hours. Here, the alkalizing apparatus 3a may be an alkali-resistant reaction vessel and used together with a conductivity meter.

Step 043: After a certain alkalization time, the alkalized mixed solution is placed in the filtration device 3b; the alkalization time here may be 1-5 hours.

Step 044: Filtering and washing the mixed solution with pure water and a filtering device 3b to remove trace metal impurities in the mixture.

Specifically, the filtering device 3b may be a ceramic membrane, so that the mixed solution may be filtered and cleaned using a ceramic membrane and purified water to remove silicon impurities. Here, the pore size of the filter pore of the ceramic membrane may be 10-200 nm, the conductivity of the purified water may be less than 5 μs, and the pH of the mixed solution to be washed is between 3-9; a self-control device may be used to control the process. The invention is not limited thereto. The filtering and cleaning process may include: adding purified water to the filtering device 3b to repeatedly filter and wash the mixed solution until the pH of the mixed solution is between 3 and 9 to complete the filtering and cleaning.

The alkalization process can remove the silicon impurities in the mixture. The reaction principle is as follows: the basic reactant reacts with the silicon impurities to form a silicate and dissolves in the alkaline solution, thereby changing the silicon impurities from the solid state to the liquid state, and further filtering It separates out.

Specifically, as shown by the broken line frame V in FIG. 4, the heavy liquid separation process may be a centrifugal process, performed under normal temperature and normal pressure conditions, using a high-speed centrifugal device h, such as a self-unloading high-speed centrifuge. Rotating speed It can be from 10,000 to 30,000 rpm, and the time can be from 30 to 300 seconds to extract the mixture. The heavy liquid separation process removes moisture from the mixture and achieves the purpose of drying the mixture.

Embodiment 2

11 is a schematic flow chart of a method for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to a second embodiment of the present invention; the method for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to the second embodiment includes The following steps:

Step 11: performing a magnetic separation process on the mixture;

Step 12: performing an acidification process on the mixture obtained in the step 11;

Step 13: performing an oxidation process on the mixture obtained in the step 12;

Step 14: subjecting the mixture obtained in the step 13 to an alkalization process;

Step 15: subjecting the mixture obtained in the step 14 to a re-acidification process;

Step 16: The mixture obtained in the step 15 is subjected to a heavy liquid separation process.

For the description of the

steps

11, 12, 13, 14, and 16, reference may be made to the

corresponding steps

01, 02, 03, 04, and 05 of the first embodiment, and details are not described herein again.

In the second embodiment, the difference from the purification method of the first embodiment is that the re-acidification process is carried out after the alkalization of the mixture and before the heavy liquid separation. The re-acidification process is to further remove trace metal ions remaining in the mixture, including K ions, Mn ions, and the like remaining in the previous oxidation process. It can be carried out in an acidification reaction chamber under normal temperature and pressure using a weak acid solution or a diluted strong acid solution. After the re-acidification process, a filtration cleaning process can also be carried out, and a ceramic membrane can be used as a filtering device, and pure water is used to obtain a mixture for removing trace metal ions.

Please refer to FIG. 12 and FIG. 13. FIG. 12 is a schematic flow chart of a re-acidification process in a process for purifying a three-dimensional graphene-coated single-particle nano-diamond material according to a preferred embodiment of the present invention; FIG. An equipment relationship diagram of the re-acidification process of the preferred embodiment. The re-acidification process of this embodiment specifically includes the following steps:

Step 151: The mixture after the alkalization process is placed in the acidic solution in the acidification device 4a;

Specifically, the mixture is placed in an acidic solution, which may be a weak acid or a diluted strong acid solution, such as diluted hydrochloric acid, sulfurous acid, carbonic acid, hypochlorous acid, hydrosulfuric acid, etc.; the acidic solution used in this embodiment is thin The concentration of hydrochloric acid and dilute hydrochloric acid may be less than 15%.

As shown in Fig. 13, there are two acidification reaction apparatuses 4a, but the number of acidification reaction apparatuses 4a is not limited in the present invention.

Step 152: Re-acidizing the mixture under normal temperature and pressure;

Specifically, under normal temperature and pressure, as shown in FIG. 13, the acidification of the acid in the acidification apparatus 4a is performed here. The reaction chamber is carried out. Here, the acidification equipment may be an acid-resistant reaction kettle and used together with a conductivity meter.

Step 153: After a certain re-acidification time, the re-acidified mixed solution is placed in the filtration device 4b;

Specifically, the re-acidification time may be 1-5 hours, for example, 2 hours, 3 hours, and the like.

Step 154: Filtering and washing the mixed solution with purified water and a filtering device 4b to remove metal ion impurities in the mixture.

Specifically, the filtering device 4b may be a ceramic membrane, so that the mixed solution may be filtered and washed with a ceramic membrane and purified water to remove metal particle impurities. Here, the pore size of the filter pore of the ceramic membrane may be 10-200 nm, the conductivity of the purified water may be less than 5 μs, and the pH of the mixed solution to be washed is between 3-9; a self-control device may be used to control the process. The invention is not limited thereto. The filtering and cleaning process may include: adding purified water to the filtering device 4b to repeatedly filter and wash the mixed solution until the pH of the mixed solution is between 3 and 9 to complete the filtering and cleaning.

The re-acidification process can remove metal ion impurities in the mixture, including removing Mn ions and K ions; this is because metal ions such as Mn ions and K ions remain in the previous oxidation process, and these metal ions and alkalization processes The alkaline reactant reacts to form a complex precipitate, and then, during the re-acidification process, the acidic solution can chemically react with the precipitate of the complex, and is converted into a chloride solution instead of being solid. It is separated from the solid three-dimensional graphene-coated single-particle nano-diamond.

In summary, by the purification method and the purification process system of the present invention, the purification rate is remarkably improved while avoiding an increase in production cost due to a large number of repeated separations; and the existing strong acid, alkali and high temperature are further avoided. The problem of shortening the life of the equipment caused by the high pressure environment, the corrosion damage to the equipment is small, the service life of the equipment is prolonged, and the cost is saved.

Although the present invention has been described in the above preferred embodiments, the embodiments are described by way of example only, and are not intended to limit the invention, and those skilled in the art can make without departing from the spirit and scope of the invention. The scope of protection claimed by the present invention is subject to the scope of the claims.

Claims

A method for purifying a three-dimensional graphene-coated single-particle nano-diamond material, which comprises purifying a mixture containing a three-dimensional graphene-coated single-particle nano-diamond material, comprising the steps of:

Step 01: performing a magnetic separation process on the mixture;

Step 02: performing an acidification process on the mixture obtained in step 01;

Step 03: performing an oxidation process on the mixture obtained in step 02;

Step 04: performing an alkalization process on the mixture obtained in step 03;

Step 05: The mixture obtained in the step 04 is subjected to a heavy liquid separation process to extract a three-dimensional graphene-coated single-particle nano-diamond material.
The purification method according to claim 1, wherein the step 04 and the step 05 further comprise: performing a re-acidification process on the mixture obtained in the step 04.
The purification method according to claim 1, wherein in the step 02, the acidifying process specifically comprises:

Step 011: placing the mixture subjected to the magnetic separation process in an acidic solution of an acidification apparatus;

Step 012: acidifying the mixture under normal temperature and pressure;

Step 013: After a certain acidification time, the acidified mixed solution is placed in a filtering device;

Step 014: Filtering and washing the mixed solution with purified water and a filtering device to remove trace metal particle impurities in the mixture.
The purification method according to claim 1, wherein in the step 03, the oxidation process specifically comprises:

Step 021: placing the mixture after the acidification process in an oxidizing solution of an oxidation device;

Step 022: performing oxidation treatment on the mixture under normal temperature and normal pressure;

Step 023: After a certain oxidation time, the oxidized mixed solution is placed in a filtering device;

Step 024: Filtering and washing the mixed solution with purified water and a filtering device to remove amorphous carbon in the mixture.
The purification method according to claim 1, wherein in the step 04, the alkalization process specifically comprises:

Step 031: placing the mixture of the oxidation process in the alkalization apparatus;

Step 032: alkalizing the mixture with an alkaline solution under normal temperature and pressure;

Step 033: After a certain alkalization time, the alkalized mixed solution is placed in a filtering device;

Step 034: Filter and wash the mixed solution with pure water and a filtering device, thereby The silicon in the mixture is removed.
The purification method according to claim 2, wherein the re-acidification process specifically comprises:

Step 151: placing the mixture after the alkalization process in a dilute hydrochloric acid solution of an acidification device;

Step 152: performing re-acidification treatment on the mixture under normal temperature and pressure;

Step 153: After a certain re-acidification time, the re-acidified mixed solution is placed in a filtering device;

Step 154: Filtering and washing the mixed solution with purified water and a filtering device to remove metal ion impurities in the mixture.
The purification method according to any one of claims 1 to 6, wherein the acidification process employs a weak acid solution; and the alkalization process employs a weak alkali solution.
The purification method according to any one of claims 1 to 6, wherein in the step 05, the heavy liquid separation process is a centrifugation process.
A purification process system for a three-dimensional graphene-coated single-particle nano-diamond material, which is characterized by purifying a mixture containing a three-dimensional graphene-coated single-particle nano-diamond material, comprising:

a magnetic separation device that performs a magnetic separation process on the mixture;

An acidification unit comprising an acidification reaction device and an acidification filtration device; the acidification device performing an acidification process on the mixture from the magnetic separation device or the alkalization unit; the acidification filtration device is a mixed solution obtained after the acidification process Performing filtration cleaning;

An oxidation unit comprising an oxidation reaction device and an oxidation filtration device; the oxidation device performing an oxidation process on the mixture coming out of the acidification unit; and the oxidation filtration device filtering and cleaning the mixed solution obtained after the oxidation process;

An alkalization unit comprising an alkalization reaction device and an alkalization filter device; the alkalization device performs an alkalization process on the mixture from the oxidation unit; the alkalized filter device is obtained after the alkalization process Mixing solution for filtration cleaning;

a heavy liquid separation unit comprising a heavy liquid separation device and a extraction device, the heavy liquid separation device performing a heavy liquid separation process on the mixture coming out of the alkalizing unit or the acidifying unit; the extraction device will be subjected to the heavy The three-dimensional graphene-coated single-particle nano-diamond material in the liquid separation process is extracted.
The purification process system according to claim 9, wherein the acidifying unit comprises a first acidifying unit and a second acidifying unit;

The first acidification unit includes a first acidification reaction device and a first acidification filtration device; the first acidification device performs a first acidification process on the mixture from the magnetic separation device; the first acidification filtration device pair The mixed solution obtained after the first acidification process is subjected to filtration cleaning;

The second acidification unit includes a second acidification reaction device and a second acidification filtration device; the second acidification device performs a second acidification process on the mixture from the alkalization unit; the second acidification filtration device is subjected to the second acidification process The resulting mixed solution was subjected to filtration washing.