JPH11197497A - Method for preventing erosion of sulfuric acid solution, sulfuric acid mist contact member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To contact a sulfuric acid solution having a high sulfuric acid concentration and a liquid temperature, a condition of contacting with a high temperature sulfuric acid mist, and a contact with a flowing sulfuric acid solution containing a suspended substance. Provided is a method for preventing erosion of a sulfuric acid solution and a sulfuric acid mist contact member, which can greatly extend the service life even under the conditions. SOLUTION: As a member that comes into contact with a sulfuric acid solution and / or a sulfuric acid mist, preferably, a graphite matrix contains Si.
_{C, B 4 C, TiC,} Mo 2 C, VC, carbon C-based ceramics is at least one selected from NbC and WC are dispersed -
Method for preventing erosion of sulfuric acid solution and sulfuric acid mist contact member using ceramic.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing erosion of a member coming into contact with a sulfuric acid solution or a sulfuric acid mist, or both, and more particularly, to a method of increasing the temperature under conditions of contact with a sulfuric acid solution having a high sulfuric acid concentration and temperature. The present invention relates to a sulfuric acid solution and a method for preventing erosion of a sulfuric acid mist contact member, which can extend the service life under conditions of contact with a sulfuric acid mist, and further under conditions of contact with a flowing sulfuric acid solution containing a suspended substance.

[0002]

2. Description of the Related Art In nonferrous smelting such as copper smelting and zinc smelting, a sulfuric acid solution is used as a solution or electrolyte in a process of dissolving or electrolytically refining raw materials such as ore. Also, in general electroplating, a sulfuric acid solution is used as an electrolytic solution. In this case, in particular, erosion of a member that comes in contact with a sulfuric acid solution or a sulfuric acid mist having a high sulfuric acid concentration and temperature, and further, a member that contains suspended substances such as precipitated nickel sulfate and contacts a flowing sulfuric acid solution. Wear was a problem.

[0003] FIG. 2 is a flow sheet showing an electrolytic refining process of copper. In FIG. 2, reference numeral 1 denotes a submerged combustion can, 2 denotes a burner for ejecting combustion gas into the liquid (hereinafter referred to as a submerged combustion burner), and 3 denotes a concentrated liquid which is a nickel sulfate-containing slurry (hereinafter also referred to as a concentrated liquid). Reference numeral 4 denotes an outlet for the concentrated liquid in the submerged combustion can 1, reference numeral 20 denotes a general electrolytic cell, reference numeral 21 denotes a copper plate (: anode), reference numeral 22 denotes a seed plate (: cathode), reference numeral 23 denotes a sulfuric acid solution, reference numeral 24 denotes a cathode copper, and reference numeral 25 denotes a product. A sorter, 26 is a circulation tank, 27 is a pure liquid electrolysis tank, and 28 is a heat exchanger.

In the copper electrolytic refining process shown in FIG.
In a general electrolytic cell 20, a copper plate 21 having a purity of about 99% produced by a converter, a refining furnace, and a cast copper machine of a smelting plant was used as an anode, and was manufactured by a seed plate electrolytic cell and a seed plate automatic stripping device. Electrorefining is performed using the seed plate 22 as a cathode. The cathodic copper 24 on the surface of which purified copper is electrolytically deposited is turned into product electrolytic copper by the product sorter 25.

On the other hand, impurities accumulate in the sulfuric acid solution, which is the electrolytic solution in the general electrolytic bath 20, and a part of the electrolytic solution is extracted and sent to the pure electrolytic bath 27 to remove impurities. The electrolytic solution from which impurities such as Sb have been removed in the pure liquid electrolytic tank 27,
After being heated to a predetermined temperature in the heat exchanger 28, it is recirculated to the general electrolytic cell 20, and a part thereof is sent to the submerged combustion can 1.

In the submerged combustion can 1, the electrolytic solution is evaporated and concentrated by a combustion product gas spouted from the submerged combustion burner 2 to deposit nickel sulfate, which is used as a nickel plating raw material or the like. . In the above-described process, a thermocouple protection tube for measuring the temperature of the submerged combustion can 1
The service life of the Pb lining applied to the concentrated liquid outlet 4 and the contact part of the test tube for checking the amount of circulation with the concentrated liquid slurry is as short as about 4 months, 3 months, and 2 months, respectively. However, the repair required a lot of man-hours, which hindered the improvement of the productivity and the safety of the electrolytic refining process.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and in particular, the conditions for contact with a sulfuric acid solution having a high sulfuric acid concentration and a high liquid temperature, and the conditions for contacting a high temperature sulfuric acid mist. Under, further, a sulfuric acid solution capable of significantly extending the service life even under conditions of contact with a flowing sulfuric acid solution containing a suspended substance, to provide a method for preventing erosion of a sulfuric acid mist contact member. Aim.

[0008]

The present inventor conducted experiments and studies on various materials in order to solve the above-mentioned problems of the prior art. As a result, the carbon-ceramic member was removed from the sulfuric acid solution of the thermocouple protection tube for measuring the temperature of the submerged combustion can 1 in the copper electrorefining step of FIG. By using as a member of the contact portion with the concentrated solution slurry of 4 and the member of the contact portion with the concentrated solution slurry of the galvanic tube, it has been found that the service life of these members can be greatly extended, The present invention has been reached.

That is, the present invention is a method for preventing erosion of a sulfuric acid solution / sulfuric acid mist contact member, wherein carbon-ceramic is used as a member for contacting the sulfuric acid solution and / or sulfuric acid mist. In the present invention, the carbon-ceramic is preferably a carbon-ceramic in which a C-based ceramic is dispersed in a graphite matrix.

In the present invention, the C-based ceramic is preferably at least one selected from the group consisting of SiC, B ₄ C, TiC, Mo ₂ C, VC, NbC and WC. Further, in the present invention, the sulfuric acid solution has a concentration of 300 g-H
It is suitably used as a method for preventing erosion of a sulfuric acid solution or a sulfuric acid mist contact member, which is a sulfuric acid solution having a solution temperature of ₂ SO ₄ / l or more and a solution temperature of 80 ° C. or more.

Further, the above-described present invention is suitably used as a sulfuric acid solution in which the sulfuric acid mist is a sulfuric acid mist in an atmosphere gas having a temperature of 80 ° C. or more, and a method for preventing erosion of a sulfuric acid mist contact member. Further, the present invention described above, 50
It is preferably applied as a method for preventing erosion of a sulfuric acid solution or a sulfuric acid mist contact member which comes into contact with a liquid sulfuric acid solution containing a solid content having a concentration of g-solid content / l or more.

The prevention of erosion of the sulfuric acid solution and sulfuric acid mist contact member in the present invention includes prevention of corrosion by sulfuric acid solution and sulfuric acid mist, prevention of oxidation by high-temperature, high-concentration sulfuric acid solution and high-temperature sulfuric acid mist, and suspension. It means prevention of abrasion by a sulfuric acid solution containing a substance and flowing, or prevention of erosion due to a combined action of these.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The carbon-ceramic member used in the present invention is a member made of a material formed by sintering carbon and ceramics together. As the carbon-ceramic member described above, it is possible to use either carbon-ceramic in which ceramics are dispersed in the matrix using carbon as a matrix, or carbon-ceramics in which carbon is dispersed in the matrix using ceramics as a matrix. However, it is preferable to use carbon-ceramics in which ceramics are dispersed in the matrix using carbon as the matrix.

Further, in the present invention, the carbon-
More preferably, the ceramic is a carbon-ceramic in which a C-based ceramic is dispersed in a graphite matrix. Further, the C-based ceramics described above include SiC, B ₄ C
, TiC, Mo ₂ C, VC, NbC and WC.

Further, the above-mentioned C-based ceramic is made of SiC
Or, it is more preferably B ₄ C or both SiC and B ₄ C. As the carbon-ceramic in which the C-based ceramic is dispersed in the graphite matrix in the present invention, the C-based ceramic is 5-80 parts by weight with respect to 100 parts by weight of graphite from the viewpoint of extending the service life against sulfuric acid solution and sulfuric acid mist. It is preferably contained.

When the amount of the C-based ceramics is less than 5 parts by weight, high-concentration, high-temperature sulfuric acid solution, liquid phase of the member due to high-temperature sulfuric acid mist, erosion based on gas-phase oxidation reaction, and erosion due to solid matter in the sulfuric acid solution. Not enough. On the other hand, if it exceeds 80 parts by weight, the notchability and impact resistance of the carbon-ceramic are reduced, and handling and machining become difficult.

Further, as the carbon-ceramic in which the C-based ceramic is dispersed in the graphite matrix according to the present invention, from the viewpoint of extending the service life of sulfuric acid solution and sulfuric acid mist, SiC, B ₄ C,
TiC, Mo ₂ C, VC, one or more selected from NbC and WC, preferably 5 to 80 parts by weight as a total amount, further, it is more preferably contained 10 to 80 parts by weight.

If the above total content is less than 5 parts by weight, high concentration, high temperature sulfuric acid solution, liquid phase of the member by high temperature sulfuric acid mist, erosion based on gas phase oxidation reaction, and solid matter in sulfuric acid solution Erosion cannot be prevented enough. Conversely, if the above total content exceeds 80 parts by weight, the notchability and impact resistance of the carbon-ceramic are reduced, and handling and machining become difficult.

By using a carbon-ceramic member as a member that comes into contact with a sulfuric acid solution and a sulfuric acid mist, the present inventor can effectively prevent erosion of the sulfuric acid solution and the sulfuric acid mist contact member, and furthermore, use a suspension such as nickel sulfate. As a result of examining the reason why it is possible to effectively prevent the abrasion of the sulfuric acid solution contact member by the flowing sulfuric acid solution containing the substance, it was conjectured that this was due to the following actions (1) to (3). .

(1): Acid resistance can be secured by using a member containing carbon such as graphite. (2): By using a member containing both carbon such as graphite and C-based ceramics such as SiC and B ₄ C, it is possible to prevent a spalling phenomenon in which a crack is generated due to a thermal factor or a mechanical factor.

(3): SiC, B _{4 using} graphite as a matrix
By using a carbon-ceramic member in which C-based ceramics such as C are dispersed, it is possible to ensure acid resistance and spalling resistance, and to use a high-concentration, high-temperature sulfuric acid solution or a high-temperature sulfuric acid mist for liquid phase. In addition to preventing the gas phase oxidation reaction, wear of the member due to solids in the sulfuric acid solution such as nickel sulfate precipitated in the sulfuric acid solution can be prevented.

It is presumed that the above-described prevention of wear of the member is due to the reinforcing effect on the graphite matrix by C-based ceramics such as SiC and B ₄ C dispersed in graphite. The carbon-ceramic member according to the present invention has a sulfuric acid solution concentration of 300 g-H ₂ SO ₄ / l or more, a liquid temperature of 80 ° C. or more,
Further, a method for preventing erosion of a sulfuric acid solution contact member having a temperature of 110 ° C. or more, an atmosphere gas temperature of 80 ° C. or more, and further, a temperature of 110 ° C.
It is preferably used as a method for preventing erosion of the contact member with the sulfuric acid mist as described above.

Further, the carbon-ceramic member according to the present invention has an atmosphere gas temperature of 80 ° C. or more,
It is more suitably used as a method for preventing erosion of a contact member with a sulfuric acid mist having a concentration of 20 mg-H ₂ SO ₄ / (Nm ³ -atmosphere gas) or more at a temperature of not lower than 20 ° C. This is because, under the use conditions of contacting with a sulfuric acid solution having a concentration of 300 g-H ₂ SO ₄ / l or more and a liquid temperature of 80 ° C. or more,
Atmospheric gas temperature is 80 ° C or higher, and the concentration is 20mg-H ₂ SO ₄
/ (Nm ³ -atmosphere gas) This is because the carbon-ceramic member according to the present invention exerts a high degree of durability under a highly erosive use environment condition of being in contact with a sulfuric acid mist which is equal to or more than the above. .

The upper limit of the temperature of the sulfuric acid solution in contact with the carbon-ceramic member and the temperature of the atmosphere in contact with the sulfuric acid mist according to the present invention is preferably 100% by weight of azeotropic mixture of sulfuric acid. It is more preferable that the temperature is 317 ° C. or lower, which is the generation temperature, and 290 ° C., which is the sulfur trioxide generation temperature of 100 wt% sulfuric acid. The upper limit of the concentration of the sulfuric acid solution with which the carbon-ceramic member according to the present invention comes into contact is not particularly limited, and the carbon-ceramic member is also used as a member that comes into contact with concentrated sulfuric acid and concentrated sulfuric acid having a reagent purity. be able to.

Further, the upper limit of the sulfuric acid concentration in the atmosphere gas in the sulfuric acid mist in contact with the carbon-ceramic member according to the present invention is not particularly limited. further,
INDUSTRIAL APPLICABILITY The present invention is preferably applied to a method for preventing erosion of a sulfuric acid solution contacting member which comes into contact with a liquid sulfuric acid solution containing a solid content having a concentration of 50 g-solid content / l or more. The above-mentioned liquid sulfuric acid solution refers to a sulfuric acid solution into which gas is blown, and a sulfuric acid solution flowing during treatment of a sulfuric acid solution or treatment of an object to be treated using the sulfuric acid solution in a sulfuric acid solution treatment apparatus of a sulfuric acid solution flowing system. The accompanying sulfuric acid solution, a sulfuric acid solution stirred by a stirrer, or a sulfuric acid solution in a state where two or three kinds are combined.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below more specifically based on embodiments. (Example 1) A carbon-ceramic member was used as a member for the contact portion of the thermocouple protection tube for measuring the temperature of the submerged combustion can 1 in the electrolytic refining step of copper shown in FIG. 2 with the sulfuric acid solution and the sulfuric acid mist. A durability test was performed.

FIG. 1 shows a submerged combustion can 1 shown in FIG.
2A and 2A are shown in FIG. In FIG. 1, reference numeral 1 denotes a submerged combustion can, 2 denotes a submerged combustion burner, and 3 denotes a concentrated solution (a sulfuric acid aqueous solution) which is a nickel sulfate-containing slurry.
(Hereinafter referred to as a concentrate) 4 is a concentrate outlet of the submerged combustion can 1, 4a is a member of the concentrate outlet, 5 is a withdrawal concentrate, and 6 is a nickel sulfate-containing sulfuric acid solution to be supplied (hereinafter, referred to as a concentrate). 7) overflow liquid, 8
Is fuel such as kerosene or heavy oil, 9 is combustion air, 10 is exhaust gas,
11 is a dip tube, 12 is a dip tube combustion tube,
13 is a circulating tube, 14 and 15 are thermocouple protection tubes for temperature measurement, 16 is an exhaust gas outlet, 17 is a submerged nozzle of liquid stirring air, and 18 is liquid stirring air.

As the members of the temperature measuring thermocouple protection tube 14 in contact with the concentrated liquid (sulfuric acid solution) 3 and the temperature measurement thermocouple protection tube 15 in contact with the sulfuric acid mist, as shown in FIG. A durability test was performed using carbon-ceramic. The test conditions were as follows. [Carbon-ceramic member:] in graphite matrix
Carbon-ceramic with SiC and B ₄ C dispersed [trade name:
KC carbon ceramics, manufactured by Nijigi Co., Ltd.]. [Sulfuric acid solution:] The sulfuric acid concentration of the sulfuric acid solution 6 supplied to the submerged combustion can; 180 g-H ₂ SO ₄ /
l, liquid temperature: 60 ° C. Sulfuric acid concentration of concentrated liquid 3 in the combustion can in liquid: 1000 g-H ₂ SO ₄ / l (: 69
wt% -H ₂ SO _4), liquid temperature: 145 ° C. solution of nickel sulfate concentration of the concentrate 3 of combustion cans: 50 to 100 g-N
iSO ₄ / l [Atmosphere of exhaust gas outlet 16:] Sulfuric acid mist atmosphere with an atmosphere gas temperature of 110 ° C and a concentration of 120 mg-H ₂ SO ₄ / (Nm ³ -atmosphere gas) As a result of the above durability test, combustion in liquid The carbon-ceramic member used as the member of the contact portion of the thermocouple protective tube 14 for temperature measurement of the can 1 with the concentrated solution (sulfuric acid solution) 3 is not affected by erosion, cracks, abrasion, etc. even after two years or more after use. No phenomenon was observed, and it was found that it was preferable to use a carbon-ceramic member as the sulfuric acid solution contact member under the above-mentioned severe use conditions.

The carbon-ceramic member used as a member for the contact portion of the thermocouple protection tube 15 for temperature measurement of the submerged combustion can 1 with the sulfuric acid mist is not affected by erosion and cracks even after one year or more after use. No phenomenon was observed, and it was found that it was preferable to use a carbon-ceramic member as the sulfuric acid mist contact member under the above-mentioned severe use conditions. (Example 2) The concentrated liquid (nickel sulfate-containing slurry) (: sulfuric acid solution) 3 of the submerged combustion can 1 shown in FIG.
A durability test was performed using the same carbon-ceramic member as in Example 1.

The test conditions were as follows. [Sulfuric acid solution:] The sulfuric acid concentration of the sulfuric acid solution 6 supplied to the submerged combustion can; 180 g-H ₂ SO ₄ /
l, liquid temperature: 60 ° C. Sulfuric acid concentration of concentrated liquid 3 in the combustion can in liquid: 1000 g-H ₂ SO ₄ / l (: 69
wt% -H ₂ SO _4), liquid temperature: 145 ° C. solution of nickel sulfate concentration of the concentrate 3 of combustion cans: 50 to 100 g-N
iSO ₄ / l As a result of the above durability test, the concentrated liquid (nickel sulfate-containing slurry) (: sulfuric acid solution) outlet 4 of the submerged combustion can 1
The carbon-ceramic member used as the member 4a at the contact portion with the nickel sulfate-containing slurry does not show erosion, cracks, abrasion, etc. even after one year or more after use, and the above-mentioned severe use conditions It has been found preferable to use a carbon-ceramic member as the sulfuric acid solution contact member.

Comparative Example 1 In Example 1 described above,
Concentrated liquid of thermocouple protection tube 14 for temperature measurement of submerged combustion can 1 (:
The same test conditions as in Example 1 except that a member with a Pb lining was used as a member of the contact portion with the sulfuric acid mist of the thermocouple protective tube 15 for temperature measurement and a member of the contact portion with the sulfuric acid mist. A durability test was performed.

As a result, in the case of the thermocouple protection tube 14 for temperature measurement, when four months have passed since the use of the Pb lining member,
Significant wear and erosion of the lining was observed, necessitating replacement of the Pb lining. In addition, in the case of the thermocouple protection tube 15 for temperature measurement, significant erosion was observed in the Pb lining in the course of four months after the use of the Pb lining member, and the Pb lining had to be replaced.

Comparative Example 2 In Example 2 described above,
Concentrate (slurry containing nickel sulfate) (sulfuric acid solution) 3
A durability test was performed under the same test conditions as in Example 2 except that a member with a Pb lining was used as the member 4a of the contact portion of the extraction port 4 with the nickel sulfate-containing slurry.

As a result, in the course of three months after the use of the Pb lining member, remarkable wear and erosion were observed in the Pb lining, and it was necessary to replace the Pb lining. In Examples 1 and 2, it was found that it was preferable to use carbon-ceramic members as the sulfuric acid solution and sulfuric acid mist contact members. A sex test was performed.

[0035] (Example 3) SiC petroleum coke and C-based _{ceramics, B 4 C, TiC, Mo} 2 C, VC, NbC and WC
After mixing, pulverizing and molding with one, two or three of the above, carbon-ceramics having the composition shown in Table 1 obtained by firing and graphitizing at 2000 ° C. were used. The test pieces of various carbon-ceramics described above were brought into contact with the concentrated liquid (sulfuric acid solution) 3 near the thermocouple protection tube 14 for temperature measurement and the thermocouple protection tube 15 for temperature measurement shown in FIG. A durability test was carried out by attaching to a contact point with a sulfuric acid mist.

The test conditions were as follows. [Sulfuric acid solution:] The sulfuric acid concentration of the sulfuric acid solution 6 supplied to the submerged combustion can; 300 g-H ₂ SO ₄ /
l, liquid temperature: 60 ° C. Sulfuric acid concentration of concentrated liquid 3 in the combustion can in liquid: 1000 g-H ₂ SO ₄ / l (: 69
wt% -H ₂ SO ₄ ), liquid temperature: 140 ° C Nickel sulfate concentration of concentrated liquid 3 of the combustion can in liquid: 200 to 400 g
-NiSO ₄ / l [Atmosphere at exhaust gas outlet 16:] Sulfuric acid mist atmosphere with an atmosphere gas temperature of 110 ° C and a concentration of 120 mg-H ₂ SO ₄ / (Nm ³ -atmosphere gas) After use of any of the carbon-ceramic test pieces (A) to (L) attached to the point of contact with the concentrated liquid (sulfuric acid solution) 3 near the thermocouple protection tube 14 for temperature measurement of the combustion can 1 No erosion, cracking, wear and other phenomena were observed even after more than two years.

The carbon-ceramic test pieces (A) to (L) attached to the contact points with the sulfuric acid mist near the thermocouple protection tube 15 for temperature measurement of the submerged combustion can 1 are used. After one year or more, no erosion or cracking phenomenon was observed. (Example 4) Test pieces of various carbon-ceramics having the same composition shown in Table 1 as in Example 3 described above were applied to a concentrated solution (nickel sulfate-containing slurry) of a submerged combustion can 1 shown in FIG.
(Sulfuric acid solution) 3 A durable test was carried out by attaching the outlet 4 to the contact portion with the nickel sulfate-containing slurry.

The test conditions were as follows. [Sulfuric acid solution:] The sulfuric acid concentration of the sulfuric acid solution 6 supplied to the submerged combustion can; 300 g-H ₂ SO ₄ /
l, liquid temperature: 60 ° C. Sulfuric acid concentration of concentrated liquid 3 in the combustion can in liquid: 1000 g-H ₂ SO ₄ / l (: 69
wt% -H ₂ SO ₄ ), liquid temperature: 140 ° C Nickel sulfate concentration of concentrated liquid 3 of the combustion can in liquid: 200 to 400 g
-NiSO ₄ / l As a result of the above-mentioned durability test, the concentrated liquid (nickel sulfate-containing slurry) (: sulfuric acid solution) of the submerged combustion can 1 (3: sulfuric acid solution) 3 In all of the ceramic test pieces (A) to (L), phenomena such as erosion, cracks, and abrasion were not observed even after more than one year from use.

[0039]

[Table 1]

[0040]

According to the present invention, under the conditions of contacting with a sulfuric acid solution having a high sulfuric acid concentration and a high liquid temperature, and under the conditions and under the conditions of contacting with a flowing sulfuric acid solution containing a suspended substance, or Under extremely harsh conditions that are in contact with high temperature sulfuric acid mist, the service life of the sulfuric acid solution and the members that come in contact with sulfuric acid mist has been
Alternatively, it is possible to greatly extend the Pb lining member, and its industrial value is extremely large.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view (a) showing a submerged combustion can and an AA view (b).

FIG. 2 is a flow sheet showing a step of electrolytic refining of copper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Submerged combustion can 2 Submerged combustion burner 3 Concentrated liquid (: sulfuric acid solution) 4 Concentrated liquid discharge port 4a Concentrated liquid discharge port member 5 Concentrated liquid discharge port 5 Extracted concentrated liquid 6 Supply sulfuric acid solution 7 Overflow liquid 8 Fuel 9 Combustion Air 10 Exhaust gas 11 Dip tube 12 Dip tube combustion tube 13 Circulating tube 14, 15 Thermocouple protection tube for temperature measurement 16 Exhaust gas outlet 17 Liquid nozzle for liquid stirring 18 Liquid stirring air 20 General electrolytic tank 21 Copper plate ( : Anode) 22 Seed plate (: Cathode) 23 Sulfuric acid solution 24 Cathode copper 25 Product sorter 26 Circulation tank 27 Purified electrolytic cell 28 Heat exchanger

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C25C 7/00 301 C04B 35/54 B

Claims (6)

[Claims] 1. A method for preventing erosion of a sulfuric acid solution / sulfuric acid mist contact member, wherein a carbon-ceramic is used as a member for contacting the sulfuric acid solution and / or sulfuric acid mist. 2. The method for preventing erosion of a sulfuric acid solution / sulfuric acid mist contact member according to claim 1, wherein the carbon-ceramic is a carbon-ceramic in which a C-based ceramic is dispersed in a graphite matrix. 3. The method according to claim 2, wherein the C-based ceramic is SiC, B ₄ C,
_{3. The} method for preventing erosion of a sulfuric acid solution and sulfuric acid mist contact member according to claim 2, wherein the member is at least one selected from TiC, Mo2C, VC, NbC and WC. 4. The sulfuric acid solution according to claim 1, wherein the sulfuric acid solution is a sulfuric acid solution having a concentration of 300 g-H ₂ SO ₄ / l or more and a liquid temperature of 80 ° C. or more. For preventing erosion of sulfuric acid mist contact members. 5. The sulfuric acid mist according to claim 1, wherein the sulfuric acid mist is a sulfuric acid mist in an atmosphere gas having a temperature of 80 ° C. or higher. Method. 6. The sulfuric acid solution according to claim 1, wherein the sulfuric acid solution is a liquid sulfuric acid solution containing a solid content of 50 g-solid content / l or more. A method for preventing erosion of contact members.