JPH07207479A - Gaseous co2 generator - Google Patents

Abstract

PURPOSE:To obtain gaseous CO2 by making carbon arranged in an acidic electrolytic solution an anode to electrolyze water. CONSTITUTION:An anodic chamber 1 and a cathodic chamber 2 are separated by a diaphragm 3 to constitute a general H type cell. A carbon rod of an anode 5 immersed in an electrolytic solution 4 is fitted to a cover 6 of the anodic chamber 1. The anode 5 is covered with a bag 8 consisting of a hydrophilic raw material to prevent the carbon rod falling off from the anode 5 during electrolysis, and the generated gaseous CO2 is taken out from a takeoff port 7. The anode 5 may be carbon powder or carbon grains. The ratio of the gaseous CO2 to oxygen generated from the anode 5 depends on kinds of carbon and current density, and generally, much gaseous CO2 is generated from carbon having advanced crystallinity, and >=90% gaseous CO2 is generated form active carbon. The electrolytic solution 4 is preferably an acid of pH <=5, and as the electrolytic solution, a solution, such as that in which water is saturated with sulfuric acid, or potassium hydrogen phthalate or potassium bitartrate about 0.01mol or 0.05mol in every 1kg is used.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a device for generating gaseous carbon dioxide, which is used in many industrial fields utilizing carbon dioxide, such as raw materials for chemical reactions, photosynthesis of plants, cell culture of animals and plants, carbonated water. It can be used for manufacturing. It can also be used in the field where a mixed gas of oxygen and carbon dioxide is supplied.

[0002]

2. Description of the Related Art Carbon dioxide is usually supplied from a cylinder. The high-pressure cylinder is heavier and has a larger volume than the contents. There is no device that generates gaseous carbon dioxide by an electrode reaction.

[0003]

SUMMARY OF THE INVENTION Gaseous carbon dioxide gas or a mixed gas of carbon dioxide gas and oxygen is generated by an electrode reaction.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a gaseous carbon dioxide gas generator, which is characterized in that water disposed in an acidic electrolyte is used as an anode to electrolyze water. All or part of the oxygen generated on the anodic carbon reacts with the anodic carbon to form carbon dioxide gas, but since the vicinity of the anode is acidic, it is hardly dissolved in water and gasified. As the carbon for the anode, various materials such as graphite, activated carbon and carbon obtained by carbonizing synthetic resin can be used. Not only pure carbon, but also a carbon kneaded product obtained by kneading and firing a substance such as resin, alumina, mica, or viscosity that does not react with the electrode can be used as the anode material. Carbon may be molded into a plate shape, a rod shape, or the like, or powder or particles may be used. In some cases it may be desirable to cover some or all of the carbon with a hydrophilic material. Carbon powder or particles may be placed in a bag formed of a hydrophilic material, and a current collector may be contacted to form the anode. In addition, carbon does not always undergo anodic reaction only from the surface, and sometimes the electrolytic solution of the acid penetrates into the carbon of the anode and reacts with it. For this purpose, a part of the case may be made of a hydrophilic material and the whole electrode may be packed in a hydrophilic bag for use. The electrolyte is P
An acid having an H5 or less is desirable, and 0.01 mol of sulfuric acid, 0.05 mol of potassium hydrogen phthalate, or a solution of saturated potassium hydrogen tartrate in a saturated solution in 1 Kg of water can be used.

Hydrogen is generated at the cathode, but when it is desired to obtain only carbon dioxide gas generated at the anode or a mixed gas of carbon dioxide gas and oxygen, the anode chamber and the cathode chamber are separated by a diaphragm or the like so that only the gas in the anode chamber is produced. Just take it out. It is convenient to provide an outlet for discharging the gas generated from the anode chamber because the gas can be taken out from the outlet.

When amorphous carbon, typified by activated carbon, is used as the anode, oxygen gas is generated less and carbon dioxide is generated at a higher rate.

[0007]

Example 1 The present invention will be described in detail with reference to examples.
1 shows a schematic cross-sectional view of Embodiment 1 of the present invention. Anode chamber 1
The cathode chamber 2 and the cathode chamber 2 are separated by a diaphragm 3 to form a general H-shaped cell. The electrolytic solution 4 is 0.1 N of sulfuric acid, and the anode 5 is a carbon rod. The carbon rod is attached to the lid 6 of the anode chamber. The gas generated at the anode is taken out from the outlet 7.
When a carbon rod obtained by kneading resin and carbon and firing is used as the carbon rod, the holes in the carbon rod are eliminated, and the reaction occurs from the electrode surface, the carbon utilization efficiency is good, and the carbon rod does not drop or collapse easily. In order to prevent carbon from falling off, the carbon rod may be covered with a bag 8 formed of a hydrophilic film. The bag and carbon may be fixed with an O-ring 9.

[0008]

Second Embodiment FIG. 2 is a schematic sectional view of a second embodiment of the present invention. The bottom of the anode chamber 1 is formed of a current collector 10, and the anode chamber is filled with carbon powder or carbon particles 11. The lead wire 12 is drawn out from the current collector, and a positive voltage is applied to the current collector and carbon in contact with the current collector. When carbon dioxide gas is generated at the anode, carbon in the anode is consumed, but in this embodiment, carbon powder or carbon particles may be added if they are gone. As the current collector, platinum, platinum-plated titanium, carbon or the like can be used.

[0009]

Other Embodiments of the Present Invention Not limited to the above embodiments, the anode may be carbon powder or carbon particles packed in a hydrophilic bag. The gas generated at the anode is mainly carbon dioxide and oxygen, but the ratio is determined by the type of carbon and the current density. Generally, carbon that is not crystallized has a higher ratio of carbon dioxide gas, and 90% or more of activated carbon is carbon dioxide gas. In systems where it is better to remove oxygen, a deoxygenation step can be used downstream of gas evolution to remove oxygen.

[0010]

According to the present invention, the amount of carbon dioxide gas generated can be controlled by the electric current. It is also more volumetrically efficient than a cylinder and does not need to handle high pressure gas. The generated gas pressure can be easily increased by making the anode chamber a pressure resistant structure. A mixed gas of carbon dioxide and oxygen can be obtained by selecting the type of anode carbon.

[0011]

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a first embodiment of the present invention.

FIG. 2 is a schematic sectional view of a second embodiment of the present invention.

[Explanation of symbols]

1: Anode chamber 2: Cathode chamber 3: Diaphragm 4: Electrolyte 5: Carbon 6: Lid 7: Outlet 8: Bag 9: O-ring
10: Current collector 11: Carbon powder or carbon particles 12: Lead wire 1
3: Cathode

Claims (3)

[Claims] 1. A gaseous carbon dioxide generating device characterized in that water is electrolyzed using carbon arranged in an acidic electrolyte as an anode. 2. The carbon dioxide generating device according to claim 1, wherein the carbon is carbon powder or particles. 3. A carbon dioxide gas generator according to claim 1 or 2, wherein a part or all of carbon of the anode is covered with a hydrophilic material.