CN113860916B - Corrosion-resistant niobium titanium carbide coating, corrosion-resistant silicon carbide container and preparation method and application thereof - Google Patents
Corrosion-resistant niobium titanium carbide coating, corrosion-resistant silicon carbide container and preparation method and application thereof Download PDFInfo
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Abstract
The invention provides a niobium titanium carbide corrosion-resistant coating, which comprises niobium carbide and titanium carbide in chemical composition. The niobium titanium carbide corrosion-resistant coating with the chemical composition can effectively prevent corrosion caused by molten fluoride-oxide, is solid in the temperature range of 1400-1800 ℃ compared with a material without a corrosion-resistant protective layer, and can effectively prevent corrosion caused by contact of electrolyte and a silicon carbide electrolytic cell so as to influence the process of electrowinning metal when applied to the surface of the silicon carbide electrolytic cell. When the niobium titanium carbide corrosion-resistant coating is used in an electrolytic cell, fe in an electrolyte can be reduced 2 O 3 、Nb 2 O 5 、TiO 2 Can react with the base material of the electrolytic cell to cause chemical erosion and can also prevent O in the electrolyte 2‑ 、F ‑ The heat erosion to the base material of the electrolytic cell can effectively ensure the smooth proceeding of the metal electrowinning.
Description
Technical Field
The invention relates to the technical field of erosion-resistant materials, in particular to an erosion-resistant niobium titanium carbide coating, an erosion-resistant silicon carbide container, and a preparation method and application thereof.
Background
The bayan obo ore is a famous iron, niobium and rare earth associated ore deposit, compared with other minerals, the bayan obo ore contains about 20% of fluorite, and the existence of the fluorides puts higher requirements on erosion-resistant materials in high-temperature experiments. Due to the existence of fluoride, the existing high-temperature ceramic material is difficult to meet the requirement of long-time work. With the requirement of carbon neutralization by peak carbon in recent years, the electrochemical clean metallurgy has been applied to the direct extraction of metals from the bayan obo minerals. When metals in the bayan obo mineral are extracted electrochemically, due to the existence of a high-temperature oxide-fluoride system, the crucible material needs to meet the requirements of high temperature resistance, electrochemical corrosion resistance, fluoride corrosion resistance, oxide corrosion resistance, electric inertia, good processability and the like, but the existing corrosion-resistant crucible material which can be used for a long time in the electrochemical metallurgy of the high-temperature oxide-fluoride system is very limited,
at present, high-temperature ceramic materials with excellent properties, such as zirconia, silicon nitride, boron nitride, silicon carbide and the like, are often used as crucible materials for high-temperature melt experiments, but when the high-temperature melt contains halides, particularly fluorides, the high-temperature ceramic materials are difficult to maintain high-temperature chemical inertness for a long time. Meanwhile, the bayan obo ore contains minerals containing iron, niobium, titanium and the like, and the minerals are easy to react with the high-temperature ceramic materials at high temperature. At present, the commonly used high-temperature ceramic materials can react with the melt to cause chemical erosion or thermal erosion, and no report of a suitable electrolytic cell material for extracting metallic iron, niobium and titanium by taking dolomite as an electrolyte is seen at present.
Disclosure of Invention
The corrosion-resistant niobium titanium carbide coating can resist long-time high-temperature corrosion of a high-temperature oxide-fluoride system, and particularly can resist long-time high-temperature corrosion and chemical corrosion of the oxide-fluoride system under the high-temperature condition below 1800 ℃.
The invention provides a niobium titanium carbide corrosion-resistant coating, which comprises niobium carbide and titanium carbide in chemical composition.
Preferably, the thickness of the niobium titanium carbide corrosion-resistant coating is 40-150 μm.
The invention provides an erosion-resistant silicon carbide container which comprises a silicon carbide container substrate and a niobium titanium carbide erosion-resistant coating adsorbed on the inner surface of the silicon carbide container substrate, wherein the niobium titanium carbide erosion-resistant coating adopts the technical scheme.
Preferably, the silicon carbide container substrate is a silicon carbide electrolytic cell.
The invention provides a raw material for preparing the niobium titanium carbide corrosion-resistant coating in the technical scheme, which comprises the following components in percentage by mass:
5 to 30 percent of CaO and 10 to 50 percent of SiO 2 5 to 40 percent of CaF 2 0 to 20 percent of CeO 2 2.5 to 25 percent of TiO 2 2.5 to 25 percent of Nb 2 O 5 And 2.5 to 25% of Fe 2 O 3 。
The invention provides a preparation method of the niobium titanium carbide corrosion-resistant coating or the corrosion-resistant silicon carbide container in the technical scheme, which comprises the following steps:
placing the raw materials in the technical scheme in a silicon carbide container substrate;
heating the silicon carbide container containing the raw materials in a protective atmosphere, raising the temperature, and then preserving the heat, wherein in the processes of raising the temperature and preserving the heat, the raw materials are changed into liquid phases to be in contact with the inner surface of the silicon carbide crucible for reaction, and the niobium titanium carbide corrosion-resistant coating is formed in the silicon carbide container matrix through in-situ high-temperature reaction, and the temperature for preserving the heat is 1300-1800 ℃.
Preferably, the heating temperature rise comprises continuous temperature rise or sectional temperature rise, and the temperature rise rate of the continuous temperature rise is 1-50 ℃/min;
the step heating comprises the following steps:
heating to an intermediate temperature at a first heating rate of 1-50 ℃/min, wherein the intermediate temperature is 500-1300 ℃;
and heating from the intermediate temperature to the heat preservation temperature at a second heating rate, wherein the second heating rate is 1-50 ℃/min, and the heat preservation temperature is 1300-1800 ℃.
Preferably, the heat preservation time is 12-48 h.
Preferably, the method further comprises the following steps after the heat preservation: and cooling and inverting the silicon carbide container obtained by heat preservation, and repeating the heating, temperature rise and heat preservation.
The invention provides application of the erosion-resistant silicon carbide container in the technical scheme in erosion resistance of molten fluoride-oxide.
The invention provides a niobium titanium carbide corrosion-resistant coating, which comprises niobium carbide and titanium carbide in chemical composition. The niobium titanium carbide corrosion-resistant coating with the chemical composition can effectively prevent molten fluoride-oxidationCompared with the material without an erosion-resistant protective layer, the niobium carbide-titanium carbide is solid within the temperature range of 1400-1800 ℃, and when the material is used on the surface of a silicon carbide electrolytic cell, the material can effectively prevent the electrolyte from contacting with the silicon carbide electrolytic cell to cause erosion so as to influence the process of electrowinning metal. When the niobium titanium carbide corrosion-resistant coating is used in an electrolytic cell, fe in an electrolyte can be reduced 2 O 3 、Nb 2 O 5 、TiO 2 Can react with the base material of the electrolytic cell to cause chemical erosion and can also prevent O in the electrolyte 2- 、F - The heat erosion to the base material of the electrolytic cell can effectively ensure the smooth proceeding of the metal electrowinning.
The invention also provides a raw material for preparing the niobium titanium carbide erosion-resistant layer and a preparation method thereof, wherein the raw material comprises CaO and SiO 2 、CaF 2 、CeO 2 、TiO 2 、Nb 2 O 5 And Fe 2 O 3 When the raw material is used for preparing the erosion-resistant layer, a silicon carbide container is used as a matrix, the raw material is added into the silicon carbide container, the temperature is increased to change the raw material into a liquid phase, the liquid phase is contacted with the silicon carbide container and reacts, the titanium carbide has high solubility on niobium carbide and silicon carbide, and niobium carbide-titanium carbide generated after the liquid phase raw material is contacted with the silicon carbide container is adsorbed on the inner surface of the silicon carbide container, so that the erosion-resistant layer containing the niobium carbide and the titanium carbide is formed.
The preparation method provided by the invention uses the container made of silicon carbide as a substrate, has good processability, the niobium titanium carbide corrosion-resistant layer prepared in situ on the inner surface of the container is not influenced by the shape of the container, and the process for preparing the corrosion-resistant layer is simple, the operation is simple and convenient, and the appearance of the corrosion-resistant layer is easy to control.
Furthermore, the method provided by the invention can increase the thickness of the erosion layer by increasing the reaction time; increasing TiO in the feedstock 2 、Nb 2 O 5 、Fe 2 O 3 (<17.5 wt.%), the compactness of the erosion layer can be improved, and the erosion resistance effect is further improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic illustration of an erosion resistant silicon carbide electrolytic cell useful in accordance with an embodiment of the present invention;
FIG. 2 is a schematic diagram of heating for preparing an erosion resistant layer by in situ high temperature reaction according to an embodiment of the present invention;
FIG. 3 is a schematic diagram illustrating salt removal in an in situ high temperature reaction for preparing an erosion resistant layer according to an embodiment of the present invention;
FIG. 4 is a scanning electron microscope image of a cross section of an erosion-resistant silicon carbide electrolytic cell prepared according to an embodiment of the present invention;
FIG. 5 is a composition diagram of a niobium titanium carbide erosion-resistant layer prepared according to an embodiment of the present invention;
FIG. 6 is a scanning electron micrograph of a titanium carbide erosion protective layer prepared according to comparative example 1 of the present invention;
FIG. 7 is a composition diagram of a titanium carbide erosion protective layer prepared in comparative example 1 of the present invention;
FIG. 8 is a scanning electron micrograph of a niobium carbide erosion protective layer prepared according to comparative example 2 of the present invention;
FIG. 9 is a composition diagram of a niobium carbide erosion protective layer prepared in comparative example 2 of the present invention;
FIG. 10 is a scanning electron micrograph of an erosion layer of titanium carbide-niobium carbide and doped with a partial salt prepared in comparative example 3 of the present invention;
FIG. 11 is a scanning electron micrograph of an erosion resistant layer prepared according to example 4 of the present invention;
FIG. 12 is a view showing a crucible having no erosion shield according to the present invention after an experiment.
Detailed Description
The invention provides a niobium titanium carbide erosion-resistant layer which comprises niobium carbide and titanium carbide in chemical composition.
The atomic ratio of niobium element to titanium element in the niobium titanium carbide erosion-resistant layer provided by the invention is preferably 1:1-1; the niobium titanium carbide erosion-resistant layer preferably comprises the following elements in atomic percentage: 54.2% of C, 34.7% of Ti and 9.8% of Nb. In the invention, the thickness of the niobium titanium carbide erosion-resistant layer is preferably 40-150 μm, and more preferably 50-150 μm; in embodiments of the present invention, the thickness of the niobium titanium carbide erosion resistant layer may be specifically 50 μm, 80 μm, 100 μm, or 150 μm.
In the invention, the niobium titanium carbide corrosion-resistant layer is applied to the surface of the silicon carbide container, and the corrosion-resistant silicon carbide container is provided. In the invention, the erosion-resistant silicon carbide container comprises a silicon carbide container substrate and a niobium carbide erosion-resistant coating adsorbed on the inner surface of the silicon carbide container substrate, wherein the niobium titanium carbide erosion-resistant coating is the niobium titanium carbide erosion-resistant coating in the technical scheme.
The invention is not limited to the kind of the silicon carbide container, and the container can be made of any silicon carbide material, such as a silicon carbide electrolytic cell and a silicon carbide crucible.
In order to prepare the niobium titanium carbide corrosion-resistant layer, the invention also provides a preparation raw material which comprises the following components in percentage by mass:
5 to 30 percent of CaO and 10 to 50 percent of SiO 2 5 to 40 percent of CaF 2 0 to 20 percent of CeO 2 2.5 to 25 percent of TiO 2 2.5 to 25 percent of Nb 2 O 5 And 2.5 to 25% Fe 2 O 3 。
In the invention, the preparation raw material preferably comprises 10-25% by mass of CaO, and more preferably 15-20%;
the preparation raw material preferably comprises 15-45 mass percent of SiO 2 More preferably 30 to 42%;
the preparation raw material preferably comprises 10-30% of CaF by mass 2 More preferably 15 to 25%, most preferably 15 to 20%;
the preparation raw material preferably comprises 2-15 mass percent of CeO 2 More preferably 5 to 10%;
the preparation raw material preferably comprisesTiO with the mass percentage of 5-20 percent 2 More preferably 7.5 to 15%;
the preparation raw material preferably comprises 4-20 mass percent of Nb 2 O 5 More preferably 5 to 15%;
the preparation raw material preferably comprises 4-20% of Fe by mass 2 O 3 More preferably 5 to 17.5%.
In the embodiment of the present invention, the preparation raw materials preferably include: 15.5% of CaO and 42% of SiO 2 20% of CaF 2 5% of CeO 2 7.5% of TiO 2 5% of Nb 2 O 5 And 5% of Fe 2 O 3 。
In the present invention, each component in the preparation raw material is preferably in a powder form, and the particle size of the powder is preferably 200 mesh or larger. In the present invention, the purity of each component in the preparation raw material is preferably >98%.
The invention also provides a preparation method for preparing the niobium titanium carbide erosion-resistant layer or the erosion-resistant silicon carbide container by using the raw materials, which comprises the following steps:
placing the raw materials in the technical scheme in a silicon carbide container substrate;
heating the silicon carbide container containing the raw materials in a protective atmosphere, raising the temperature, and then preserving the heat, wherein in the processes of raising the temperature and preserving the heat, the raw materials are changed into liquid phases to be in contact with the inner surface of the silicon carbide crucible for reaction, and the niobium titanium carbide corrosion-resistant coating is formed in the silicon carbide container matrix through in-situ high-temperature reaction, and the temperature for preserving the heat is 1300-1800 ℃.
According to the invention, the raw material is placed in the silicon carbide container substrate, preferably, the raw material is prepared and molded, and then the obtained molded body is placed in the silicon carbide container substrate. In the present invention, the method of molding is preferably tableting; the pressure of the tabletting is preferably 3-10 MPa, and the pressure maintaining time of the tabletting is preferably 2-15 min. In the present invention, the molded body is preferably a disk, and the diameter of the disk is preferably 10 to 30mm. The tabletting equipment used in the present invention is not particularly limited, and powder tabletting machines known to those skilled in the art can be used.
In the present invention, the ratio of the mass of the raw material to the volume of the silicon carbide container substrate is preferably 1:1 to 1:3
After the raw materials are placed in a silicon carbide container matrix, the silicon carbide container with the raw materials is heated in a protective atmosphere to raise the temperature and then is insulated, in the processes of raising the temperature and insulating the temperature, the raw materials are changed into liquid phases to be in contact with the inner surface of the silicon carbide crucible to react, the niobium carbide titanium corrosion-resistant coating is formed in the silicon carbide container matrix through in-situ high-temperature reaction, and the insulation temperature is 1300-1800 ℃.
The heating and heat-preserving equipment is not particularly limited, and a heating furnace known by a person skilled in the art can be adopted, specifically, a silicon carbide container containing raw materials is placed in the heating furnace, as shown in fig. 2, a protective gas outlet is arranged at the top of the heating furnace, and a protective gas inlet is arranged at the bottom of the heating furnace. The protective atmosphere is not particularly limited by the present invention, and a protective gas known to those skilled in the art may be used, and in the embodiment of the present invention, the protective gas is preferably argon.
In the present invention, the heating temperature rise is preferably a continuous temperature rise or a stepwise temperature rise, and in the present invention, the temperature rise rate of the continuous temperature rise is preferably 1 to 50 ℃/min, more preferably 5 to 40 ℃/min, and most preferably 10 to 20 ℃/min.
In the present invention, the stepwise temperature rise preferably includes the steps of:
heating to an intermediate temperature at a first heating rate of 1-50 ℃/min, wherein the intermediate temperature is 500-1300 ℃;
and heating from the intermediate temperature to the heat preservation temperature at a second heating rate, wherein the second heating rate is 1-50 ℃/min, and the heat preservation temperature is 1300-1800 ℃.
The temperature is kept after the temperature is raised to the heat preservation temperature, the heat preservation time is preferably 12-48 h, and in the embodiment of the invention, the heat preservation time can be 12h, 15h, 20h, 24h, 30h, 35h, 40h, 45h or 48h.
In the present invention, the first temperature increase rate is preferably 5 to 40 ℃/min, more preferably 10 to 20 ℃/min; the intermediate temperature is preferably 700 to 1200 deg.c, more preferably 1000 deg.c. In the present invention, the second temperature increase rate is preferably 5 to 40 ℃/min, more preferably 10 to 20 ℃/min; the intermediate temperature is preferably 1400 to 1600 deg.c, more preferably 1500 deg.c. In the processes of heating and heat preservation, the raw materials are melted into a liquid phase, the liquid phase raw materials are in contact with the inner surface of the silicon carbide for reaction, and niobium carbide and titanium carbide are generated in situ in the silicon carbide container, wherein the specific reaction process is as follows:
SiC+Fe 2 O 3 →Fe/FeSi/Fe 3 C+SiO 2 +CO/CO 2 ；
SiC+Nb 2 O 5 →NbC+SiO 2 ；
SiC+TiO 2 →TiC+SiO 2 ；
Fe 3 C+Nb 2 O 5 →Fe+TiC+CO；
Fe 3 C+TiO 2 →Fe+TiC+CO。
after the heat preservation, the invention preferably turns the silicon carbide container obtained by heat preservation upside down after cooling, and repeats the heating and heat preservation. The cooling method is not particularly limited in the present invention, and cooling technical schemes known to those skilled in the art, such as furnace cooling, can be adopted.
After cooling, the invention preferably inverts the cooled silicon carbide container and repeats the heating and holding. In the embodiment of the present invention, as shown in fig. 3, a cooled silicon carbide container is suspended upside down in a heating furnace using molybdenum wires, and a silicon carbide container having a larger size is placed on the periphery of the silicon carbide container for protection. In the present invention, the repeated heating and temperature raising and maintaining are the same as the heating and temperature raising and maintaining scheme described in the above technical scheme, and are not described herein again. In the embodiment of the present invention, the holding time in the repeated heating and warming and holding is preferably 6 hours.
According to the invention, the raw materials are fully reserved from the silicon carbide container through inversion and repeated heating, temperature rise and heat preservation, and the niobium titanium carbide erosion-resistant layer is formed in situ on the inner surface of the silicon carbide container.
The method provided by the invention generates the niobium titanium carbide erosion-resistant layer on the inner surface of the silicon carbide container in situ, thereby having longer-time high-temperature erosion resistance and chemical erosion resistance when being used for melting a fluoride-oxide system.
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
It should be noted that, in the case of no conflict, the features in the following embodiments and examples may be combined with each other; moreover, all other embodiments that can be derived by one of ordinary skill in the art from the embodiments disclosed herein without making any creative effort fall within the scope of the present disclosure.
It is noted that various aspects of the embodiments are described below within the scope of the appended claims. It should be apparent that the aspects described herein may be embodied in a wide variety of forms and that any specific structure and/or function described herein is merely illustrative. Based on the disclosure, one skilled in the art should appreciate that one aspect described herein may be implemented independently of any other aspects and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented and/or a method practiced using any number of the aspects set forth herein. Additionally, such an apparatus may be implemented and/or such a method may be practiced using other structure and/or functionality in addition to one or more of the aspects set forth herein.
Example 1
CaO-SiO raw material used in examples 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 The components are shown in Table 1
TABLE 1 CaO-SiO employed in example 1 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 Ingredients of raw materials
| Composition (I) | CaO | SiO 2 | CaF 2 | CeO 2 | TiO 2 | Nb 2 O 5 | Fe 2 O 3 |
| Content (wt%) | 15.5 | 42 | 20 | 5 | 7.5 | 5 | 5 |
Weighing 3.21g of powder raw materials according to the proportion of each oxide, pressing the powder raw materials into a wafer with the diameter of 13mm by using a powder tablet press, setting the pressure to be 5Mpa, and keeping the pressure for 5min;
putting the obtained wafer into a silicon carbide electrolytic cell, putting the silicon carbide electrolytic cell with the wafer into a heating furnace for heating (the heating schematic diagram is shown in figure 2), heating from room temperature to 1000 ℃ at the heating rate of 10 ℃/min in the argon protective atmosphere, then heating from 1000 ℃ to 1500 ℃ at the heating rate of 5 ℃/min, preserving heat for 24h at 1500 ℃, cooling along with the furnace, and taking out the electrolytic cell;
and inversely hanging the heated electrolytic cell in a heating furnace by using a molybdenum wire, placing a silicon carbide crucible with larger size on the periphery of the electrolytic cell to protect the heating furnace, heating the sample to 1500 ℃ according to the temperature rise step, preserving the heat for 6 hours to ensure that the sample in the electrolytic cell fully flows out of the electrolytic cell, forming a niobium titanium carbide erosion-resistant layer on the inner surface of the silicon carbide electrolytic cell in situ, and heating and reserving a schematic diagram as shown in figure 3.
The electrolytic cell was cut along the axial direction and examined by scanning electron microscopy, and the results are shown in fig. 4 and 5, from the results of scanning electron microscopy, a relatively dense niobium carbide-titanium carbide corrosion-resistant protective layer had been formed on the inner surface of the silicon carbide electrolytic cell, and 24 hours after the electrolyte was in sufficient contact with the electrolytic cell, a relatively dense niobium carbide-titanium carbide corrosion-resistant protective layer having a thickness of about 95 μm had been formed by the above-mentioned chemical reaction.
Example 2
CaO-SiO raw material used in examples 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 The components are shown in Table 2
TABLE 2 CaO-SiO used in example 2 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 Ingredients of raw materials
| Composition (I) | CaO | SiO 2 | CaF 2 | CeO 2 | TiO 2 | Nb 2 O 5 | Fe 2 O 3 |
| Content (wt%) | 5 | 10 | 5 | 5 | 25 | 25 | 25 |
Weighing 5g of powder raw materials according to the proportion of each oxide, pressing the powder raw materials into a wafer with the diameter of 30mm by using a powder tablet press, setting the pressure to be 10Mpa, and keeping the pressure for 15min;
putting the obtained wafer into a silicon carbide electrolytic cell, putting the silicon carbide electrolytic cell with the wafer into a heating furnace for heating (the heating schematic diagram is shown in figure 2), heating from room temperature to 500 ℃ at the heating rate of 50 ℃/min in the argon protective atmosphere, then heating from 500 ℃ to 1450 ℃ at the heating rate of 8 ℃/min, preserving heat for 48h at 1450 ℃, and taking out the electrolytic cell after furnace cooling;
and inversely hanging the heated electrolytic cell in a heating furnace by using a molybdenum wire, placing a silicon carbide crucible with a larger size at the periphery of the electrolytic cell to protect the heating furnace, heating the sample to 1450 ℃ and preserving the temperature for 6 hours according to the temperature rise step, so that the sample in the electrolytic cell can sufficiently flow out of the electrolytic cell, forming a niobium titanium carbide erosion-resistant layer in situ on the inner surface of the silicon carbide electrolytic cell, and heating to reserve a schematic diagram as shown in fig. 3.
And cutting the electrolytic bath along the axial direction, and performing scanning electron microscope detection, wherein according to the result of the scanning electron microscope, a relatively compact niobium carbide-titanium carbide corrosion-resistant protective layer is generated on the inner surface of the silicon carbide electrolytic bath, and the relatively compact niobium carbide-titanium carbide corrosion-resistant protective layer with the thickness of about 150 mu m is generated by the chemical reaction after the electrolyte formed by melting the oxide-fluoride melt is fully contacted with the electrolytic bath for 24 hours.
Example 3
CaO-SiO raw material used in examples 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 The ingredients are shown in Table 3
TABLE 3 CaO-SiO as used in example 3 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 Ingredients of raw materials
| Composition (I) | CaO | SiO 2 | CaF 2 | CeO 2 | TiO 2 | Nb 2 O 5 | Fe 2 O 3 |
| Content (wt%) | 10 | 40 | 30 | 12.5 | 2.5 | 2.5 | 2.5 |
Weighing 1.5g of powder raw materials according to the proportion of each oxide, pressing the powder raw materials into a wafer with the diameter of 10mm by using a powder tablet press, setting the pressure to be 3Mpa, and keeping the pressure for 2min;
putting the obtained wafer into a silicon carbide electrolytic cell, putting the silicon carbide electrolytic cell with the wafer into a heating furnace for heating (the heating schematic diagram is shown in figure 2), heating from room temperature to 1400 ℃ at the heating rate of 5 ℃/min in the argon protective atmosphere, then heating from 1400 ℃ to 1600 ℃ at the heating rate of 5 ℃/min, preserving heat for 12h at 1600 ℃, cooling along with the furnace, and taking out the electrolytic cell;
and inversely hanging the heated electrolytic cell in a heating furnace by using a molybdenum wire, placing a silicon carbide crucible with larger size on the periphery of the electrolytic cell to protect the heating furnace, heating the sample to 1600 ℃ according to the temperature rise step, preserving the heat for 6 hours to ensure that the sample in the electrolytic cell fully flows out of the electrolytic cell, forming a niobium titanium carbide erosion-resistant layer in situ on the inner surface of the silicon carbide electrolytic cell, and heating and reserving a schematic diagram as shown in figure 3.
And cutting the electrolytic bath along the axial direction, carrying out scanning electron microscope detection, and according to the result of the scanning electron microscope, generating a compact niobium carbide-titanium carbide corrosion-resistant protective layer on the inner surface of the silicon carbide electrolytic bath, wherein the compact niobium carbide-titanium carbide corrosion-resistant protective layer with the thickness of about 40 mu m is generated by the chemical reaction after the electrolyte is in full contact with the electrolytic bath for 24 hours.
Comparative example 1
With the composition shown in Table 4 (without Fe) 2 O 3 And Nb 2 O 5 Time) the raw materials in example 1 were replaced, and an erosion-resistant layer was formed on the inner surface of the silicon carbide electrolytic cell according to the protocol of example 1.
TABLE 4 composition of raw materials used in comparative example 1
| Composition (A) | CaO | SiO 2 | CaF 2 | CeO 2 | TiO 2 |
| Content (wt%) | 17.2 | 46.7 | 22.2 | 5.6 | 8.3 |
The scanning electron microscope examination of the silicon carbide electrolytic cell obtained by the invention shows that the results are shown in fig. 6 and 7, and the titanium carbide corrosion protection layer is obtained by the comparative example.
Comparative example 2
With the composition shown in Table 5 (i.e., without Fe) 2 O 3 And TiO 2 ) The procedure of example 1 was followed except that carbon was used in place of the starting material in example 1Preparing an erosion resistant layer on the inner surface of the silicon-melting electrolytic bath.
TABLE 5 composition of raw materials used in comparative example 2
| Composition (I) | CaO | SiO 2 | CaF 2 | CeO 2 | Nb 2 O 5 |
| Content (wt%) | 17.7 | 48 | 22.9 | 5.7 | 5.7 |
The scanning electron microscope examination of the silicon carbide electrolytic cell obtained by the present invention showed that the results of the examination are shown in fig. 8 and 9, and the niobium carbide erosion protective layer was obtained in the comparative example.
By comparing the scanning electron microscope images of the corrosion protection layer of niobium carbide and titanium carbide and the main components, the Fe content is determined 2 O 3 、TiO 2 、Nb 2 O 5 The niobium carbide-titanium carbide corrosion protection layer formed in the presence of the niobium carbide-titanium carbide corrosion protection layer is more compact, the main components of the niobium carbide-titanium carbide corrosion protection layer are mainly niobium carbide and titanium carbide, and the niobium carbide-titanium carbide corrosion protection layer which is singly present is sandwiched in the niobium carbide or titanium carbide corrosion protection layerMixed with more salt, the corrosion protection effect is not as good as that of the niobium carbide-titanium carbide corrosion protection layer.
Comparative example 3
With the composition shown in Table 6 (i.e., without Fe) 2 O 3 ) An erosion-resistant layer was prepared on the inner surface of the silicon carbide electrolytic cell according to the protocol of example 1, replacing the raw materials in example 1.
TABLE 6 composition of raw materials used in comparative example 3
| Composition (I) | CaO | SiO 2 | CaF 2 | CeO 2 | Nb 2 O 5 | TiO 2 |
| Content (wt%) | 16.2 | 44.2 | 21.1 | 5.3 | 5.3 | 7.9 |
The scanning electron microscope examination of the silicon carbide electrolytic cell obtained by the present invention showed that the result is shown in fig. 10, and the erosion layer of titanium carbide-niobium carbide and doped partial salt was obtained in the present comparative example.
Example 4
TABLE 7 CaO-SiO used in example 4 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 Ingredients of raw materials
| Composition (I) | CaO | SiO 2 | CaF 2 | CeO 2 | TiO 2 | Nb 2 O 5 | Fe 2 O 3 |
| Content (wt%) | 15.5 | 42 | 20 | 5 | 7.5 | 5 | 5 |
Weighing 3.21g of powder raw materials according to the proportion of each oxide, pressing the powder raw materials into a wafer with the diameter of 13mm by using a powder tablet press, setting the pressure to be 5Mpa, and keeping the pressure for 5min;
putting the obtained wafer into a silicon carbide electrolytic cell, putting the silicon carbide electrolytic cell with the wafer into a heating furnace for heating (the heating schematic diagram is shown in figure 2), heating from room temperature to 1000 ℃ at the heating rate of 10 ℃/min in the argon protective atmosphere, then heating from 1000 ℃ to 1500 ℃ at the heating rate of 5 ℃/min, and preserving heat at 1500 ℃ for 24 hours to generate an erosion protective layer, taking out the electrolytic cell after furnace cooling, and then repeating the heating and heat preserving steps and carrying out five experiments to test the performance of the erosion protective layer;
after the experiment, the electrolytic bath was cut in the axial direction and examined by scanning electron microscopy, and as a result, as shown in fig. 11, the thickness of the erosion resistant layer on the inner surface of the silicon carbide electrolytic bath was about 100 μm, and the change in thickness was not large as compared with the erosion protective layer of example 1.
Comparative example 4
TABLE 8 CaO-SiO for comparative example 4 2 -CaF 2 -CeO 2 -TiO 2 -Nb 2 O 5 -Fe 2 O 3 Ingredients of raw materials
| Composition (I) | CaO | SiO 2 | CaF 2 | CeO 2 | Fe 2 O 3 |
| Content (wt%) | 17.7 | 48 | 22.9 | 5.7 | 5.7 |
Weighing 3.21g of powder raw materials according to the proportion of each oxide, pressing the powder raw materials into a wafer with the diameter of 13mm by using a powder tablet press, setting the pressure to be 5Mpa, and keeping the pressure for 5min;
putting the obtained wafer into a silicon carbide electrolytic cell, putting the silicon carbide electrolytic cell with the wafer into a heating furnace for heating (the heating schematic diagram is shown in figure 2), heating from room temperature to 1000 ℃ according to the heating rate of 10 ℃/min in the argon protective atmosphere, then heating from 1000 ℃ to 1500 ℃ according to the heating rate of 5 ℃/min, and preserving heat for 24 hours at 1500 ℃, wherein the raw material does not contain TiO 2 、Nb 2 O 5 The other experimental conditions were the same except that the corrosion protective layer could not be formed.
FIG. 12 is a graph showing the results of tests conducted on a crucible having no erosion layer, and it was found that the thickness of the electrolyte erosion in the electrolytic bath was 600 to 1200 μm when no erosion layer was present.
The comparison shows that the corrosion-resistant protective layer is formed in situ on the inner surface of the electrolytic cell, so that the problem of using CaO-SiO to effectively solve 2 -CaF 2 -REO-TiO 2 -Nb 2 O 5 -Fe 2 O 3 The system is used for solving the problem of corrosion of electrolyte to an electrolytic bath in the process of carrying out electrolytic extraction on metal by the electrolyte.
The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (8)
1. The corrosion-resistant silicon carbide container comprises a silicon carbide container substrate and a niobium titanium carbide corrosion-resistant coating adsorbed on the inner surface of the silicon carbide container substrate, wherein the niobium titanium carbide corrosion-resistant coating comprises niobium carbide and titanium carbide in chemical composition.
2. The erosion-resistant carbonization container of claim 1, wherein the niobium titanium carbide erosion-resistant coating has a thickness of 40 to 150 μm.
3. The erosion-resistant silicon carbide container of claim 1 or 2 wherein the silicon carbide container substrate is a silicon carbide electrolyzer.
4. A method of making the erosion resistant silicon carbide container of any one of claims 1~3 comprising the steps of:
placing raw materials for preparing the niobium titanium carbide corrosion-resistant coating in the corrosion-resistant silicon carbide container into a silicon carbide container substrate, wherein the raw materials comprise the following components in percentage by mass: 5 to 30 percent of CaO and 10 to 50 percent of SiO 2 5 to 40% CaF 2 0 to 20% of CeO 2 2.5 to 25 percent of TiO 2 2.5 to 25 percent of Nb 2 O 5 And 2.5 to 25% of Fe 2 O 3 ；
Heating the silicon carbide container matrix containing the raw materials in a protective atmosphere, raising the temperature, and then preserving the heat, wherein in the processes of raising the temperature and preserving the heat, the raw materials are changed into liquid phases to be in contact with the inner surface of the silicon carbide container matrix for reaction, and the in-situ high-temperature reaction is carried out in the silicon carbide container matrix to form the niobium-titanium carbide corrosion-resistant coating, and the temperature for preserving the heat is 1300-1800 ℃.
5. The preparation method according to claim 4, wherein the heating comprises continuous heating or step heating, and the heating rate of the continuous heating is 1 to 50 ℃/min;
the step heating comprises the following steps:
heating to an intermediate temperature at a first heating rate of 1-50 ℃/min, wherein the intermediate temperature is 500-1300 ℃;
and heating from the intermediate temperature to the heat preservation temperature at a second heating rate, wherein the second heating rate is 1-50 ℃/min, and the heat preservation temperature is 1300-1800 ℃.
6. The method for preparing the polyurethane foam according to claim 4 or 5, wherein the time for heat preservation is 12 to 48h.
7. The method according to claim 4 or 5, further comprising, after the incubation: and cooling and inverting the silicon carbide container obtained by heat preservation, and repeating the heating, temperature rise and heat preservation.
8. Use of the erosion resistant silicon carbide container of any one of claims 1~3 for resisting erosion of molten fluoride-oxide.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4029466A (en) * | 1974-08-08 | 1977-06-14 | Denki Kagaku Kogyo Kabushiki Kaisha | Container for evaporation of metal |
| CN1215708A (en) * | 1997-10-27 | 1999-05-05 | 普拉塞尔技术有限公司 | Method for producing corrosion resistant refractories |
| CN101925455A (en) * | 2007-11-21 | 2010-12-22 | 丹佛斯公司 | Object having ductile and corrosion resistant surface layer |
| CN104060147A (en) * | 2014-06-21 | 2014-09-24 | 上海君山表面技术工程股份有限公司 | Corrosion resistant coating and preparation method thereof |
| CN104204274A (en) * | 2012-02-24 | 2014-12-10 | 梯尔镀层有限公司 | Coating with conductive and corrosion resistance characteristics |
| CN107429414A (en) * | 2015-04-23 | 2017-12-01 | 俄铝工程技术中心有限责任公司 | Electrode of aluminum electrolysis cell (variant) |
| CN109112534A (en) * | 2018-09-29 | 2019-01-01 | 西安文理学院 | A kind of high density titanium carbide composite anti-wear coating and preparation method thereof |
| CN109252159A (en) * | 2018-09-29 | 2019-01-22 | 西安文理学院 | A kind of niobium carbide gradient composite coating and preparation method thereof |
| CN109680276A (en) * | 2019-01-28 | 2019-04-26 | 西安理工大学 | A kind of complex phase carbide coating/titanium-niobium alloy based composites and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050064247A1 (en) * | 2003-06-25 | 2005-03-24 | Ajit Sane | Composite refractory metal carbide coating on a substrate and method for making thereof |
| CN112151276B (en) * | 2020-09-15 | 2022-05-24 | 宇启材料科技南通有限公司 | Electrode foil, method for producing same, and electrolytic capacitor |
-
2021
- 2021-09-14 CN CN202111083862.1A patent/CN113860916B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4029466A (en) * | 1974-08-08 | 1977-06-14 | Denki Kagaku Kogyo Kabushiki Kaisha | Container for evaporation of metal |
| CN1215708A (en) * | 1997-10-27 | 1999-05-05 | 普拉塞尔技术有限公司 | Method for producing corrosion resistant refractories |
| CN101925455A (en) * | 2007-11-21 | 2010-12-22 | 丹佛斯公司 | Object having ductile and corrosion resistant surface layer |
| CN104204274A (en) * | 2012-02-24 | 2014-12-10 | 梯尔镀层有限公司 | Coating with conductive and corrosion resistance characteristics |
| CN104060147A (en) * | 2014-06-21 | 2014-09-24 | 上海君山表面技术工程股份有限公司 | Corrosion resistant coating and preparation method thereof |
| CN107429414A (en) * | 2015-04-23 | 2017-12-01 | 俄铝工程技术中心有限责任公司 | Electrode of aluminum electrolysis cell (variant) |
| CN109112534A (en) * | 2018-09-29 | 2019-01-01 | 西安文理学院 | A kind of high density titanium carbide composite anti-wear coating and preparation method thereof |
| CN109252159A (en) * | 2018-09-29 | 2019-01-22 | 西安文理学院 | A kind of niobium carbide gradient composite coating and preparation method thereof |
| CN109680276A (en) * | 2019-01-28 | 2019-04-26 | 西安理工大学 | A kind of complex phase carbide coating/titanium-niobium alloy based composites and preparation method thereof |
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