JP2000199004A - Lead oxide or lead, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a homogeneous lead oxide with specified oxygen content or lead high in purity, and its manufacturing method. SOLUTION: Powder lead dioxide (PbO2) of 200 g in raw lead oxide is placed in a reducing container 5 in a body 2 of a reducing furnace 1, the body 2 is evacuated, hydrogen (H2) gas is allowed to flow at the flow rate of 300 cc/min, the reducing container 5 is heated and kept at the temperature of 600 deg.C for five hours to obtain metallic lead (Pb) of 165 g. Similarly, powder lead dioxide (PbO2) of 200 g is placed in the reducing container 5, the mixture gas of 20% hydrogen gas and 80% argon gas is allowed to flow at the flow rate of 300 cc/min, and the reducing container 5 is heated and kept at 500 deg.C for ten hours to obtain lead monoxide (PbO) of 180 g.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to lead oxide or lead and a method for producing the same, and more particularly, to lead oxide or lead containing a predetermined amount of oxygen produced by reducing raw material lead oxide and a method for producing the same. It is about the method.

[0002]

2. Description of the Related Art Lead (Pb) is used as an electrode for a lead storage battery, as an electrode for covering a cable, as an electrode for soldering, and as a raw material for a stabilizer of a vinyl chloride resin, as a raw material for a solder alloy, and has a low melting point. It is also widely used as a raw material for lead glass having an expansion coefficient. Pb naturally exists mainly as galena or sulfide ore (PbS), but Pb is produced by separating the galena ore from other metal sulfides by flotation and then to 500 ° C. in a blast furnace. PbO (lead monoxide) and P
bSO ₄ (lead sulfate)
With S, or the resulting PbO is further reduced by carbon monoxide gas to a purity of 98 to 99%.
And is withdrawn from the bottom of the blast furnace as a molten liquid.

[0003] Pb oxides have an oxidation number of 1,
There are two or four compounds and multiple oxides, generally PbO
(Lead monoxide), Pb ₃ O ₄ (trilead tetroxide), Pb ₂ O ₃
(Lead trioxide) and PbO ₂ (lead dioxide) are known. These various types of lead oxides are produced by oxidizing metal Pb. For example, PbO is Pb
Is put into an oxidizing furnace or reverberatory furnace, melted, and the surface is mixed well and brought into contact with air to obtain crude PbO.
Since this crude PbO contains Pb, it is further put into a muffle furnace, baked at a temperature of about 600 ° C., and then pulverized to obtain a product PbO. Pb ₃ O ₄ is obtained by placing crude PbO in a muffle furnace, oxidizing at a temperature of 400 ° C. to 500 ° C. and pulverizing the product, and having a purity of 85% to 98%.
It is about. In addition, a mixed composition of PbO and Pb, also called lead suboxide, melts Pb and has a diameter of 2 mm or more.
It is manufactured by molding into a cylindrical shape having a height of 3 mm and a height of 3 mm to 4 mm, and blowing the air into a rotating drum while rotating. That is, the surfaces of the molded products are oxidized by being rubbed against each other and heated to a temperature of about 200 ° C., so that a mixed composition of PbO and Pb is obtained as a fine powder.

[0004]

SUMMARY OF THE INVENTION Lead monoxide (PbO) is used as a raw material for lead glass having a low melting point and a low coefficient of thermal expansion. A solder alloy containing lead and tin contains a small amount of oxygen. Since alloys are preferred because of their higher melting rates, lead oxide is often used as a raw material, such as using lead oxide as a raw material for solder alloys.However, conventional methods for producing lead oxide use lead oxide. It is difficult to produce a homogeneous and highly pure lead oxide having a predetermined value of the amount of oxygen contained in, that is, the number of oxygen atoms with respect to the number of lead atoms. In particular, it is very difficult to control the oxygen content of lead oxide, as shown as a mixed composition of PbO and Pb, to a predetermined value. In addition, since lead is immediately oxidized in the air but does not reach the inside, it usually contains almost no oxygen (O), and even if it does, the oxygen content cannot be controlled.

The present invention has been made in view of the above problems, and has as its object to provide lead oxide or lead having a ratio of the number of oxygen atoms to the number of lead atoms within a predetermined range, and a method for producing the same.

[0006]

According to the present invention, there is provided a method comprising:
The problem is solved by the configuration of claim 3, claim 5, or claim 7, and the means for solving them will be described below.

The lead oxide according to claim 1 is powdered lead dioxide.
(PbO_Two ), Lead trioxide (Pb_Two O _Three ), Trilead tetroxide
(Pb_Three O_Four )) Or a mixture of two or more
Compound is reduced by reducing gas, and lead
The ratio of the number of oxygen atoms to the number of atoms is given by the following equation: 1.33 / 1
≥ the number of oxygen atoms / the number of lead atoms ≥ 1/1
Is the lead oxide inside. Such lead oxides are uniformly reduced
As a result, oxygen atoms remain evenly.

[0008] The lead oxide according to claim 2 dependent on claim 1 is:
It is a homogeneous lead oxide that is simply and uniformly reduced by at least one of hydrogen gas, water gas and carbon monoxide gas alone or a mixed gas with an inert gas.

In a third aspect of the present invention, there is provided a method for producing lead oxide, which comprises any one of powdery lead dioxide (PbO ₂ ), dilead trioxide (Pb ₂ O ₃ ), and trilead tetroxide (Pb ₃ O ₄ ). The ratio of the number of oxygen atoms to the number of lead atoms of one or a mixture of two or more is represented by the following formula: 1.33 / 1 ≧ the number of oxygen atoms / the number of lead atoms ≧ 1
/ 1 is a production method in which reduction is carried out with a reducing gas so as to fall within the range indicated by / 1. Such a manufacturing method
The raw material lead oxide is uniformly reduced to give lead oxide in which oxygen atoms remain evenly.

The method for producing lead oxide according to claim 4 is dependent on claim 3, wherein at least one of hydrogen gas, water gas and carbon monoxide gas alone or a mixed gas with an inert gas is used. This is a production method that uses as a reducing gas, and reduces raw material lead oxide easily and uniformly.

The lead oxide or lead according to claim 5 is lead dioxide.
(PbO_Two ), Lead trioxide (Pb_Two O _Three ), Trilead tetroxide
(Pb_Three O_Four )) Or a mixture of two or more
Powder monoxide obtained by reducing or thermally decomposing the compound
Lead (PbO) or powder obtained by oxidizing lead (Pb)
Powdered lead monoxide (PbO) is reduced by reducing gas
Ratio of the number of oxygen atoms to the number of lead atoms
Is the following formula, 1/1> the number of oxygen atoms / the number of lead atoms ≧ 0/1,
Is lead oxide or lead in the range indicated by. This
Lead oxide is uniformly reduced and oxygen atoms remain evenly.
And lead is of high purity.

The lead oxide or lead according to claim 6 which is dependent on claim 5 is hydrogen gas, water gas or carbon monoxide gas alone or a mixed gas with an inert gas. It is lead oxide or lead uniformly reduced and homogeneous.

[0013] The method for producing lead oxide or lead according to claim 7 comprises:
Powder obtained by reducing or thermally decomposing any one or a mixture of two or more of lead dioxide (PbO ₂ ), dilead trioxide (Pb ₂ O ₃ ), and trilead tetroxide (Pb ₃ O ₄ ) Lead monoxide (PbO) or powdery lead monoxide obtained by oxidizing lead (Pb) is obtained by converting the ratio of the number of oxygen atoms to the number of lead atoms into the following formula: 1/1> oxygen atom This is a production method in which reduction is performed with a reducing gas such that the number / atom number of lead ≧ 0/1. Such a production method reduces the raw material lead oxide easily and uniformly, and gives lead oxide in which oxygen atoms remain evenly and lead with high purity.

According to a seventh aspect of the present invention, there is provided a lead oxide or a method for producing lead, wherein at least one of hydrogen gas, water gas and carbon monoxide gas is used alone, or mixed with an inert gas. This is a production method using a gas as a reducing gas, in which raw material lead oxide is reduced simply and uniformly.

[0015]

Lead oxide or lead and its manufacturing method of the embodiment of the present invention, the powdered lead dioxide (PbO _2), trioxide lead (Pb ₂ O _3), triiron tetraoxide lead (Pb ₃ O ₄ ) Is used as the raw material lead oxide, and the ratio of the number of oxygen atoms to the number of lead atoms is represented by the following formula:
33/1 ≧ the number of oxygen atoms / the number of lead atoms ≧ 1/1, the lead oxide produced by reduction with a reducing gas, and the powdered lead monoxide ( Pb
Using O) as the raw material lead oxide, the ratio of the number of oxygen atoms to the number of lead atoms is expressed by the following formula: 1/1> the number of oxygen atoms / the number of lead atoms ≧
Although it is lead oxide or lead produced by reduction with a reducing gas so as to fall within the range shown by 0/1, embodiments thereof will be described in detail below.

Powdered lead dioxide (PbO) as a raw material
₂ ), lead trioxide (Pb ₂ O ₃ ), lead tetroxide (Pb ₃
O ₄ ) or lead monoxide (PbO) is preferably industrially manufactured from the viewpoint of clear purity and supply stability. These raw material lead oxides are more preferably in a fine powder state having a large surface area in order to allow the reduction reaction to proceed uniformly and quickly.

In the reduction, it is preferable to use a reducing gas in view of easy control of the flow rate and temperature and easy handling.
As the reducing gas, at least one of hydrogen gas, water gas, and carbon monoxide gas depends on the type of raw material lead oxide, powder shape, oxygen content of lead oxide finally obtained, and the like. Selected. In addition, in order to make the reduction conditions mild if necessary, an inert gas
For example, a rare gas such as an argon gas or a helium gas may be mixed at a fixed ratio.

In the reduction, powdery raw material lead oxide is placed in a reduction vessel in a closed type reduction furnace equipped with a heating mechanism, and the temperature is 500 ° C.
It is performed by heating to a temperature of ~ 600 ° C, introducing a reducing gas from one end of the reduction furnace, and exhausting from the other end. Since the reducing gas is in uniform contact with the powdery raw material lead oxide, the reduction proceeds uniformly and uniformly, and a homogeneous lead oxide containing a predetermined amount of oxygen or high-purity metal lead can be obtained.
The reduction reaction proceeds stably and quickly by heating the reduction vessel to a temperature of 500 ° C to 600 ° C. From PbO ₂ , Pb ₂ O ₃ , Pb ₃ O _{4 of} powdery raw material lead oxide to Pb
In the case of reduction to obtain O, the reduction reaction all proceeds in a powder state at the above heating temperature. In addition, powdery raw material P
In the case of reduction to finally obtain Pb from bO, at the above-mentioned heating temperature, Pb becomes a molten liquid, and in the middle thereof,
The process proceeds in a state where powdered PbO is floating in the melt of Pb. In any case, by passing a preset time, homogeneous lead oxide containing a predetermined amount of oxygen or highly pure metal lead can be obtained.

FIG. 1 is a schematic partial cutaway side view of a reduction furnace 1 as a typical example. The entire reduction furnace 1 is made of stainless steel. Blind flanges 4a and 4b are respectively attached to flanges 3a and 3b at both ends of a horizontal cylindrical main body 2 by bolts to form a closed system. A reduction container 5 is installed in the main body 2, and the main body 2 corresponding to the reduction container 5 is provided.
An electric furnace 8 having a built-in heater 6 and heat insulating material 7
Are wound, and cooling water pipes 9 a and 9 are provided at both ends of the main body 2.
b is wound. In addition, hydrogen (H ₂ ) gas as a reducing gas can be introduced into the main body 2 from the blind flange 4a side alone or as a mixed gas with argon gas. That is, following the hydrogen gas cylinder 11, an inlet pipe 15 provided with a variable flow valve 12, a flow meter 13, and a valve 14 is inserted into the blind flange 4a. In addition, the variable flow valve 1 is connected to the argon gas cylinder 16.
7. A pipe 19 provided with a flow meter 18 is a hydrogen gas introduction pipe 1.
5 is inserted between the flow meter 13 and the valve 14 to be integrated.

On the side of the blind flange 4b, a vacuum exhaust pipe 21 provided with a vacuum gauge 22 and an opening / closing valve 23 in the middle is mounted, and is connected to a vacuum pump 24. The vacuum pump 24 is used for evacuating the inside of the main body 2 before introducing the reducing gas into the main body 2.
Further, on the upstream side of the opening / closing valve 23, the evacuation pipe 21
An exhaust pipe 26 is branched together with the valve 25, and the reducing gas is exhausted in a steady state of the reducing operation.
Further, a thermocouple terminal 2 for temperature measurement is provided in the reduction vessel 5.
7 is inserted, and its lead wire 28 is connected to a temperature measurement control system 29 provided outside the main body 2.
The control system 29 controls heating by the electric furnace 8.

The amount of oxygen contained in the lead oxide or lead obtained by reduction is determined by the amount of water (H ₂ O) and carbon dioxide in the atmosphere in the reduction furnace 1 adsorbed by the lead oxide or lead. After removing (CO ₂ ), the mixture is heated and dissolved in a graphite crucible in an electric furnace for measurement, and oxygen is reacted with carbon in the graphite crucible to obtain carbon monoxide gas (CO). Further, this CO is brought into contact with heated copper monoxide (CuO) to be converted into carbon dioxide gas (CO ₂ ), and the generated C
It is analyzed by quantifying the amount of O ₂ gas by an infrared absorption method. As an analysis method, in addition to the above, it is also possible to obtain from the mass difference between the raw material lead oxide and the lead oxide or lead obtained by reduction. In addition, spectroscopic analysis using characteristic X-rays, for example, X-ray microanalysis method is also available. Applicable.

Powdered lead dioxide (PbO) as a raw material
₂ ), lead trioxide (Pb ₂ O ₃ ), lead tetroxide (Pb ₃
O ₄ ) is reduced under a reducing atmosphere using one or a mixture of two or more of O ₄ ), and the ratio of the number of oxygen atoms to the number of lead atoms is expressed by the following formula: 1.33 / 1 By setting the number of atoms of oxygen to the number of atoms of lead ≧ 1/1, a lead oxide between Pb ₃ O ₄ and Pb0 can be obtained.

Further, as a raw material, powdery lead monoxide (P
b0) is reduced in a reducing atmosphere, and the ratio of the number of oxygen atoms to the number of lead atoms is within the range of the following expression: 1/1> the number of oxygen atoms / the number of lead atoms ≧ 0/1. The lead oxide between Pb0 and Pb, in other words, P
Lead oxide or metal Pb is obtained as a mixed composition of bO and Pb in an arbitrary ratio. In this case, the raw material powder Pb0 includes the above-mentioned PbO ₂ , Pb ₂ O ₃ , Pb ₃
O either one or other of Pb0 obtained by reducing a mixture of two or more of the _{4, PbO 2, Pb 2 O} 3, P
Any one or a mixture of two or more of b ₃ O ₄ is thermally decomposed into PbO, or Pb is oxidized to form PbO.
Those made into bO can be used similarly.

In the above, Pb of the raw material lead oxide is used.
Reducing the lead oxide between Pb ₃ O ₄ and PbO using O ₂ , Pb ₂ O ₃ and Pb ₃ O ₄ ; The step of reducing to lead oxide or metal Pb has been described separately, but it goes without saying that these steps can be performed continuously.

[0025]

EXAMPLES Hereinafter, the lead oxide or lead of the present invention and a method for producing the same will be specifically described with reference to examples.

(Example 1) In a reduction vessel 5 in a main body 2 of a reduction furnace 1 shown in FIG.
200 g of O ₂ ) powder, and a vacuum pump 2
After evacuating to a vacuum degree 10 ^-1 Pa by 4, close-off valve 23, a variable flow valve 12 opened a hydrogen gas cylinder 11 and flow rate control, 300 cc of hydrogen (H ₂₎ gas from the inlet pipe 15 into the main body 2 / Min flow rate,
Air was exhausted from the exhaust pipe 26. At the same time, heating the reduction vessel 5,
It was kept at a temperature of 600 ° C. for 5 hours. As a result, 173 g of metallic lead (Pb) was obtained based on the following reaction formula. That is, PbO ₂ was reduced to high-purity Pb via PbO. PbO ₂ + 2H ₂ = Pb + 2H ₂ O

(Example 2) In the same manner as in Example 1, 200 g of powder of trilead tetroxide (Pb ₃ O ₄ ) was placed as a raw material lead oxide in a reduction vessel 5 in a main body 2 of a reduction furnace 1. 2 was evacuated, and then hydrogen (H ₂ ) gas was supplied at 200 cc / m 2.
The flow was in. At the same time, the reducing vessel 5 is heated to 60
It was kept at a temperature of 0 ° C. for 10 hours. As a result, 181 g of metallic lead (Pb) was obtained based on the following reaction formula.
That is, Pb ₃ O ₄ was reduced to high-purity Pb via PbO. Pb ₃ O ₄ + 4H ₂ = 3Pb + 4H ₂ O

(Example 3) In the same manner as in Example 1, 200 g of powder of trilead tetroxide (Pb ₃ O ₄ ) was placed as a raw material lead oxide in a reduction vessel 5 in a main body 2 of a reduction furnace 1. in after evacuating the 2, opening the hydrogen gas cylinder 11 and the argon gas cylinder 16, the flow rate was adjusted for each variable flow valve 12 and the variable flow valve 17, hydrogen from the introduction pipe 15 into the main body 2 (H ₂₎ gas 20 % / Argon gas 80% was introduced at a flow rate of 200 cc / min and exhausted from the exhaust pipe 26. At the same time, the reduction vessel 5 is heated to 500
C. for 5 hours. As a result, 195 g of lead monoxide (Pb0) was obtained based on the following reaction formula. Pb ₃ O ₄ + H ₂ = 3PbO + H ₂ O

Example 4 In the same manner as in Example 3, 200 g of lead dioxide (PbO ₂ ) powder as raw material lead oxide was placed in a reduction vessel 5 in a main body 2 of a reduction furnace 1, and the inside of the main body 2 was evacuated. After evacuation, a mixed gas of hydrogen (H ₂ ) gas 20% and argon gas 80% was flowed at a flow rate of 300 cc / min. At the same time, the reduction vessel 5 is heated,
Hold for hours. As a result, 187 g of lead monoxide (PbO) was obtained based on the following reaction formula. PbO ₂ + H ₂ = PbO + H ₂ O

The lead oxide or lead and the method for producing lead according to the embodiment of the present invention are constructed and operated as described above.
Of course, the present invention is not limited to these, and various modifications are possible based on the technical idea of the present invention.

For example, in the present embodiment, PbO ₂ powder or Pb ₃ O ₄ powder is used alone as the raw material lead oxide, but the powdery raw material lead oxide including these is used alone. Or may be used as a mixture. Reduction temperature, mixing ratio of reducing gas with inert gas,
The flow rate, reduction time and the like are appropriately set depending on the type of the raw material lead oxide and the oxygen content of the lead oxide to be obtained. In the present embodiment, hydrogen gas is used as the reducing gas,
Argon gas was used as an inert gas mixture.
As an inert gas, nitrogen gas may be used in addition to a noble gas such as argon gas.

In the present embodiment, the reduction vessel 5
The lead melt formed therein is not stirred, but may be stirred by electromagnetic induction.

[0033]

The lead oxide or lead and the method for producing the same according to the present invention are implemented in the above-described embodiment, and have the following effects.

According to the lead oxide of the first aspect, the ratio of the number of oxygen atoms to the number of lead atoms is represented by the following formula: 1.33 / 1 ≧ the number of oxygen atoms / the number of lead atoms ≧ 1/1. Since the oxygen atoms are contained evenly in the lead oxide within the range described above, the products using them are homogeneous. According to the lead oxide of the second aspect, since the reduction is performed easily and uniformly, a low-cost lead oxide having stable characteristics is provided.

According to the method for producing lead oxide of the third aspect, the ratio of the number of oxygen atoms to the number of lead atoms is expressed by the following equation: 1.33 /
Since oxygen atoms are uniformly contained in the lead oxide in the range of 1 ≧ the number of oxygen atoms / the number of lead atoms ≧ 1/1, the products using these as raw materials are homogenized. According to the method for producing lead oxide of the fourth aspect, since the reduction is performed easily and uniformly, the obtained lead oxide has stable characteristics and low cost.

According to the lead oxide or lead of the present invention, the ratio of the number of oxygen atoms to the number of lead atoms is represented by the following formula: 1/1> the number of oxygen atoms / the number of lead atoms ≧ 0/1. Oxide or lead within the specified range has stable properties and low cost. According to the lead oxide or lead of claim 6, since the reduction is performed easily and uniformly, low-cost lead oxide or lead having stable characteristics is provided.

According to the method for producing lead oxide or lead of claim 7, the ratio of the number of oxygen atoms to the number of lead atoms is expressed by the following formula:
/ 1> the number of oxygen atoms / the number of lead atoms ≥ 0/1, for lead oxide or lead in the range shown, lead oxide contains oxygen evenly and lead has high purity. Homogenize the products using them. According to the method for producing lead oxide or lead according to claim 8, since the reduction is performed easily and uniformly, low-cost lead oxide or lead having stable characteristics is provided.

[Brief description of the drawings]

FIG. 1 is a partially broken side view of a reduction device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reduction furnace 2 Main body 5 Reduction vessel 8 Electric furnace 11 Hydrogen gas cylinder 15 Introducing pipe 16 Argon gas cylinder 26 Exhaust pipe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01B 3/12 340 H01B 3/12 340 H01M 4/16 H01M 4/16 Z 4/38 4/38 Z 4 / 56 4/56 // B23K 35/26 310 B23K 35/26 310B (72) Inventor Eiji Maekawa 516 Yokota, Sanmu-cho, Sanmu-gun, Chiba Japan Vacuum Metallurgy Co., Ltd. 4-2-1, Ichimoto Fujisawa, Ebara Corporation (72) Inventor Junichiro Yoshioka 4-2-1, Fujisawa, Fujisawa, Kanagawa Prefecture F-term in Ebara Corporation 4K017 AA03 BA01 EH01 EH18 FB05 4K018 BA20 5G303 AA06 CB25 5H003 BB02 BB04 5H016 EE01 EE05

Claims (8)

[Claims] 1. One or a mixture of two or more of powdered lead dioxide (PbO ₂ ), dilead trioxide (Pb ₂ O ₃ ), and trilead tetroxide (Pb ₃ O ₄ ) are reduced. And the ratio of the number of oxygen atoms to the number of lead atoms is 1.33 / 1 ≧ the number of oxygen atoms / the number of lead atoms ≧ 1
The lead oxide which is within the range shown by / 1. 2. The method according to claim 1, wherein the reducing gas is hydrogen gas, water gas,
2. The lead oxide according to claim 1, wherein at least one of the carbon monoxide gases is used alone, or is a mixed gas with an inert gas. 3. One or a mixture of two or more of powdered lead dioxide (PbO ₂ ), dilead trioxide (Pb ₂ O ₃ ), and trilead tetroxide (Pb ₃ O ₄ ) The ratio of the number of oxygen atoms to the number of lead atoms is given by the following equation: 1.33 / 1 ≧ number of oxygen atoms / number of lead atoms ≧ 1
/ 1. A method for producing lead oxide, comprising reducing with a reducing gas so as to fall within the range represented by / 1. 4. The oxidation according to claim 3, wherein at least one of hydrogen gas, water gas, and carbon monoxide gas is used alone, or a mixed gas with an inert gas is used as the reducing gas. Lead production method. 5. Lead dioxide (PbO ₂ ), dilead trioxide (P
b ₂ O _3), triiron tetraoxide lead (Pb ₃ O ₄₎ either one or powdery lead monoxide obtained by a mixture of two or more reduction or thermal decomposition to one of (PbO), or lead ( P
Powdered lead monoxide (PbO) obtained by oxidizing b) is reduced by a reducing gas, and the ratio of the number of oxygen atoms to the number of lead atoms is expressed by the following formula 1/1> oxygen atom Lead oxide or lead, wherein the number / atom number of lead ≧ 0/1. 6. The lead oxide or lead according to claim 5, wherein the reducing gas is at least one of hydrogen gas, water gas, and carbon monoxide gas alone, or a mixed gas with an inert gas. . 7. Lead dioxide (PbO ₂ ), lead trioxide (P
b ₂ O _3), triiron tetraoxide lead (Pb ₃ O ₄₎ either one or powdery lead monoxide obtained by a mixture of two or more reduction or thermal decomposition to one of (PbO), or lead ( P
powdered lead monoxide (PbO) obtained by oxidizing b)
Is reduced with a reducing gas so that the ratio of the number of oxygen atoms to the number of lead atoms is within the range represented by the following formula: 1/1> oxygen atom number / lead atom number ≧ 0/1. Characteristic method for producing lead oxide or lead. 8. The oxidizing method according to claim 7, wherein at least one of hydrogen gas, water gas and carbon monoxide gas is used alone, or a mixed gas with an inert gas is used as said reducing gas. Lead or a method for producing lead.