Device for preparing MXene by adopting alkali etching
The preparation of MXene using an alkaline etching device solves the harm to human health and the environment caused by the preparation of MXene with hydrofluoric acid, and achieves high-yield and environmentally friendly MXene preparation. Byproducts can be recycled and the etching time is shortened.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-28
- Publication Date
- 2026-04-07
AI Technical Summary
The existing technology for preparing MXene using hydrofluoric acid has problems such as being highly harmful to human health and the environment, being highly corrosive, and having byproducts that are difficult to remove.
An alkaline etching apparatus is used, which includes components such as a steam generator, nitrogen charging, a high-temperature reaction vessel, a gas-liquid separator, and a centrifuge, to prepare MXene through alkaline etching, thereby achieving effective recovery of by-products and resource recycling.
It avoids the use of hydrofluoric acid, reduces environmental risks, increases the yield of monolayer MXene to over 70%, and shortens the etching time to 3.4~8 hours.
Smart Images
Figure CN224086703U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to etching device technical field, concretely relates to a device of preparation MXene with alkali etching. BACKGROUND
[0002] In 2011, researchers of Drexel University in the United States prepared a new type of two-dimensional material: MXene by using a method of selective etching bulk material. The method obtains transition metal carbon / nitride two-dimensional material by etching A atom layer in MAX phase material (a kind of ternary layered structure material).
[0003] MAX phase is a general term for a class of ternary layered compounds, and the compounds have a general chemical formula M n+1 AX n Wherein, M is an early transition metal, A is a group III and IV element, X is C or N, and n=1, 2, 3, etc. The structural characteristics of MAX phase are that M atoms and A atom layers are arranged alternately to form a nearly close-packed hexagonal layered structure, and X atoms are filled in the octahedral void. The M-A bond has the characteristics of metal bond, and the force is relatively weak compared with M-X bond.
[0004] In a hydrofluoric acid solution, the A atom layer of the MAX phase is easy to be etched, and the M and X atom layers are left to form a two-dimensional Mn+1Xn atomic crystal. In order to emphasize that they are peeled from the MAX phase and have a two-dimensional structure similar to graphene+, they are collectively named MXene. At present, the synthesis method of MXene generally uses high-concentration HF or a mixture of fluoride and strong acid to etch the A atom layer in the MAX phase. Although this method is effective, it has the following disadvantages: it is harmful to the human body and the environment; and inert functional groups can reduce the performance of the material (for example, capacitance, etc.); in addition, the HF solution not only corrodes the AI layer, but also corrodes the transition metal elements in the MXene structure; more importantly, some etching by-products are insoluble in any solvent under mild conditions, and it is difficult to remove them from the prepared MXene.
[0005] Based on the above situation, a synthesis method and device without fluorine and capable of etching acidic elements are needed to prepare MXene. INVENTION CONTENTS
[0006] In view of the technical problems in the prior art that the preparation of MXene by using hydrofluoric acid is harmful to the human body and the environment and has a low yield, the utility model provides a device for preparing MXene by using alkali etching.
[0007] The utility model provides a kind of device for preparing MXene using alkali etching, including steam generator, steam generator is provided with the cavity of containing water and the heating element of heating water in cavity, steam generator is connected with high temperature reaction tank, steam generated by steam generator enters into high temperature reaction tank by steam pipeline, high temperature reaction tank is provided with the storage rack of loading reactant, high temperature reaction tank is connected with the nitrogen filling assembly of filling nitrogen into high temperature reaction tank, high temperature reaction tank top is also provided with water shower assembly, the output end of high temperature reaction tank is connected with gas-liquid separator by first pipeline, the output end of gas-liquid separator is connected with self-stripping reaction tank by second pipeline, the output end of self-stripping reaction tank is connected with centrifugal separator by third pipeline, self-stripping reaction tank is also connected with intercalation agent storage tank capable of injecting intercalation agent into self-stripping reaction tank by fourth pipeline.
[0008] Further, the high temperature reaction tank is connected with a steam circulation assembly for recycling steam, and the steam circulation assembly comprises a steam circulation pump and a condenser.
[0009] Further, the high temperature reaction tank is also connected with a waste gas treater.
[0010] Further, the high temperature reaction tank is provided with a pressure sensor and a temperature sensor.
[0011] Further, the utility model also comprises a central controller, which is connected with the pressure sensor and the temperature sensor, and is connected with the centrifugal separator to control the rotating speed of the centrifugal separator.
[0012] Further, the self-stripping reaction tank is provided with a stirring assembly and / or an ultrasonic assembly.
[0013] Further, the gas-liquid separator is a cyclone separator.
[0014] Further, the output end of the intercalation agent storage tank or the fourth pipeline is provided with a peristaltic pump for controlling the flow of the intercalation agent.
[0015] Further, the nitrogen filling assembly comprises a nitrogen generator or a nitrogen storage tank.
[0016] Further, the high temperature reaction tank is provided with multiple layers of storage racks from top to bottom, and the port of the steam pipeline for inputting steam into the high temperature reaction tank is arranged at the lower part of the high temperature reaction tank.
[0017] The device of the utility model avoids the use of hydrogen fluoride (HF) in traditional processes, eliminates the problems of strong acid corrosion, toxicity and waste liquid treatment, and greatly reduces environmental risks. The by-products can be effectively recycled to realize resource recycling. The single-layer MXene yield is ≥70% through intercalation agent-induced self-stripping. The device of the utility model can complete etching within 3.4-8h, and shorten the etching time. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This is a structural schematic diagram of one embodiment of the present invention.
[0020] Explanation of main reference numerals: 1-Steam generator, 11-Steam pipe, 2-High temperature reaction vessel, 21-First pipe, 22-Thermocouple, 23-Pressure sensor, 24-Shelf, 3-Gas-liquid separator, 32-Second pipe, 4-Self-stripping reaction vessel, 43-Third pipe, 44-Fourth pipe, 5-Centrifuge, 6-Steam circulation assembly, 7-Waste gas processor, 8-Central controller, 9-Stirring assembly, 10-Intercalating agent storage tank. Detailed Implementation
[0021] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.
[0022] like Figure 1 As shown, one embodiment of this utility model provides an apparatus for preparing MXene using alkaline etching, including a steam generator. The steam generator is provided with a water-containing cavity and a heating element for heating the water in the cavity. The heating element heats the water in the cavity to a high temperature to generate high-temperature and high-pressure steam. The inner wall material is silicon carbide ceramic. The steam enters a high-temperature reaction vessel through a steam pipe. The steam enters from the bottom of the high-temperature reaction vessel. The steam temperature is 250~400℃. The steam pipe is a high-temperature resistant alloy pipe. The steam flow rate is controlled by a flow valve.
[0023] The high-temperature reaction tank is connected with a nitrogen filling assembly for filling nitrogen into the high-temperature reaction tank. The nitrogen filling assembly includes a nitrogen generator or a nitrogen storage tank. The MAX phase and sodium hydroxide mixture stirred uniformly is placed on a multi-layer shelf in the high-temperature reaction tank. The nitrogen generator or the nitrogen storage tank fills nitrogen into the high-temperature reaction tank to discharge the air inside the equipment. After the water vapor enters the high-temperature reaction tank, the MAX phase and sodium hydroxide mixture are contacted to perform etching. The multi-layer shelf arranged in the high-temperature reaction tank can improve the contact efficiency of the water vapor and the reactants, thereby improving the etching efficiency. The bottom outlet of the high-temperature reaction chamber is connected with a gas-liquid separator through a heat-insulated first pipeline. The gas-liquid separator separates the mixed gas after the reaction and the solid product, and is preferably a cyclone separator. A thermocouple and a pressure sensor are arranged in the high-temperature reaction tank to monitor the temperature and pressure inside the high-temperature reaction tank. According to the monitored temperature and pressure values, the reaction conditions in the high-temperature reaction tank are adjusted to make the temperature, pressure and environmental factors always meet the environmental conditions of etching. The thermocouple and the pressure sensor are connected to a central controller. The central controller receives the information of the thermocouple and the pressure sensor and displays the information on a display. The etching time in the high-temperature reaction tank is 4-8 hours. After the etching is completed, the upper water shower assembly performs water showering to wash the unreacted sodium hydroxide to the lower liquid collection port. Subsequently, the MXene after the alkali etching is transported to the gas-liquid separator through the first pipeline. The MXene powder is transported to the self-stripping reaction tank with the gas. The unreacted MAX phase and the reaction by-products are collected at the bottom of the cyclone separator. The water shower assembly includes a water tank, a water pump, a water shower pipeline and a spray nozzle. The water pump extracts water in the water tank along the water shower pipeline to the spray nozzle and then sprays downward. The water shower washes the unreacted sodium hydroxide. The high-temperature reaction tank is connected with a steam circulation assembly for recycling the steam. The steam circulation assembly includes a steam circulation pump and a condenser. The steam circulation pump separates the unreacted steam from the condenser. After condensation, the steam is re-injected into the steam generator to realize the recycling of the steam. The high-temperature reaction tank is also connected with a waste gas treatment device. In one embodiment, the waste gas treatment device adopts a catalytic combustion method and is provided with a combustion chamber to combust and treat the hydrogen gas discharged from the high-temperature reaction tank.
[0024] The MXene powder enters the self-stripping reaction tank. An intercalation agent is added to the self-stripping reaction tank to realize the stripping of the MXene. The self-stripping reaction tank is provided with a stirring assembly or an ultrasonic assembly to make the intercalation agent and the MXene fully contact and improve the stripping efficiency. The self-stripping reaction tank is also connected with an intercalation agent storage tank through a fourth pipeline. A peristaltic pump is arranged at the output end of the fourth pipeline or the intercalation agent storage tank to control the flow of the intercalation agent transported to the self-stripping reaction tank. The output end of the self-stripping reaction tank is connected with a centrifugal separator through a third pipeline. The MXene after the stripping is cleaned and separated by the centrifugal separator. The central controller is connected with the centrifugal separator to control the rotating speed of the centrifugal separator and display the rotating speed on a display.
[0025] Although the utility model has been described in detail by referring to the drawings and in conjunction with the preferred embodiments, the utility model is not limited thereto. Without departing from the spirit and essence of the utility model, those skilled in the art can make various equivalent modifications or replacements to the embodiments of the utility model, and these modifications or replacements shall be within the scope of the utility model. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the utility model, and all shall be covered within the protection scope of the utility model.
Claims
1. An apparatus for preparing MXene using alkaline etching, characterized in that, The system includes a steam generator, which has a water-containing chamber and a heating element for heating the water in the chamber. The steam generator is connected to a high-temperature reaction vessel. The steam generated by the steam generator enters the high-temperature reaction vessel through a steam pipe. The high-temperature reaction vessel is equipped with a shelf for loading reactants. The high-temperature reaction vessel is connected to a nitrogen-filling assembly for filling the high-temperature reaction vessel with nitrogen. A water spray assembly is also installed above the high-temperature reaction vessel. The output end of the high-temperature reaction vessel is connected to a gas-liquid separator through a first pipe. The output end of the gas-liquid separator is connected to a self-peeling reaction vessel through a second pipe. The output end of the self-peeling reaction vessel is connected to a centrifuge through a third pipe. The self-peeling reaction vessel is also connected to an intercalating agent storage tank through a fourth pipe, which can inject intercalating agent into the self-peeling reaction vessel.
2. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, The high-temperature reaction vessel is connected to a steam circulation assembly for recovering steam, which includes a steam circulation pump and a condenser.
3. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, The high-temperature reaction vessel is also connected to an exhaust gas processor.
4. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, The high-temperature reaction vessel is equipped with pressure sensors and temperature sensors.
5. The apparatus for preparing MXene by alkaline etching as described in claim 4, characterized in that, It also includes a central controller, which is connected to pressure sensors and temperature sensors, and is connected to the centrifuge to control the speed of the centrifuge.
6. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, The self-peeling reaction vessel is equipped with a stirring assembly; and / or, the self-peeling reaction vessel is equipped with an ultrasonic assembly.
7. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, The gas-liquid separator is a cyclone separator.
8. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, The output end of the intercalating agent storage tank or the fourth pipeline is equipped with a peristaltic pump to control the flow rate of the intercalating agent.
9. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, Nitrogen filling components include a nitrogen generator or a nitrogen storage tank.
10. The apparatus for preparing MXene by alkaline etching as described in claim 1, characterized in that, The high-temperature reaction vessel is equipped with multiple shelves from top to bottom, and the steam inlet for the steam pipe is located at the bottom of the high-temperature reaction vessel.