JPS6028276B2 - How to operate an anaerobic globe box - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of operating an anaerobic glove box for treating or culturing anaerobic bacteria, and its purpose is to improve safety and operability. be.

In an anaerobic glove box for treating or culturing secondary anaerobic bacteria, in order to create an anaerobic atmosphere,
After replacing the air in the glove box with a mixture of nitrogen, carbon dioxide, and hydrogen, the residual oxygen or the oxygen that gradually enters from the outside is combined with hydrogen and oxygen using a heated palladium catalyst to form water. It was removed using this method.

However, mixed gases containing hydrogen are dangerous, and palladium catalysts have a short lifespan, so they must be constantly reprocessed. The present invention seeks to eliminate these drawbacks.

That is, the present invention avoids the use of hydrogen and palladium catalysts by applying an electrochemical deoxygenation device to an anaerobic glove box. First, to explain the electrochemical deoxidizer, the gas diffusion electrode used in fuel cells is used as the cathode, the anode is an inert electrode, and the gas diffusion electrode of the electrolytic cell is used with sulfuric acid or intestinal ion exchange membrane as the electrolyte. While contacting a mixed gas containing
When a DC voltage is applied between the negative and anode electrodes, the following reactions occur at the cathode and anode.

Cathode: 0214H + Juukasa - → is LO Anode: 2LO → 0214 day Jujukasa - In other words, only oxygen is selectively consumed at the cathode, and oxygen is generated at the anode.

Therefore, if the oxygen generated at the anode is discharged to the outside of the system,
The electrolyzer described above acts as an oxygen scavenger. Connect this electrochemical oxygen deoxidizer to a conventional anaerobic glove box,
Removing the oxygen in the glove box not only eliminates the need for hydrogen but also eliminates the need for palladium catalysts. However, if the oxygen in the glove box were to be removed only by an electrochemical deoxidizing light, only 210 cc of oxygen could be removed with the amount of electricity of the IAh, so there is a problem that the time required for deoxidizing is generally too long. On the other hand, if an attempt is made to increase the deoxidation speed, a large number of electrolytic cells must be used, resulting in the problem that the electrochemical deoxidation device becomes too large. In order to deal with the problem of
The present invention employs a method in which the air in the glove box is replaced in advance with carbon dioxide gas or a mixed gas of carbon dioxide gas and an inert gas, and then residual oxygen is removed using an electrochemical deoxidizer. In other words, by adopting this method, most of the oxygen in the glove box is removed remotely by carbon dioxide gas or a mixture of carbon dioxide gas and inert gas, so only electrochemical deoxidation layer can be used. The deoxidation speed will be faster than when deoxidizing with .

At the same time, carbon dioxide gas necessary for culturing anaerobic bacteria is supplied. Activation of the electrochemical deoxidizer may begin simultaneously with the initiation of gas replacement. On the other hand, the airtightness of an anaerobic glove box is generally not necessarily perfect, and even if the glove box is deoxidized, oxygen will enter from outside the glove box over time.

This problem can be solved by leaving the power switch of the electrochemical deoxidizer on all the time. In other words, the electrochemical deoxidizer requires the power switch to be turned on at all times.
As long as oxygen is present, current will flow between the cathode and anode and oxygen will be automatically removed. This point is also one of the important features of the present invention. An embodiment of the present invention will be described in detail below.

Embodiment 1 FIG. 1 shows a schematic diagram of the cross-sectional structure of an anaerobic glove box according to an embodiment of the present invention.

In Figure 1, 1 is the glove box, 2 is the spare room, and 3 is the glove box.
is an electrochemical deoxidizer, a mixed gas cylinder of 4 carbon dioxide gas and nitrogen gas (5% carbon dioxide gas). The electrochemical deoxidizer 3 includes a cathode 5 made of a gas diffusion electrode, an anode 6 made of a titanium plate coated with iridium and platinum as an oxygen generating electrode, an electrolytic solution 7 made of sulfuric acid, a gas chamber 8,
It is composed of an oxygen outlet 9. The electrochemical deoxidizer 3 is connected to the preliminary chamber 2 via a circulation pump 10 and a vacuum compensator 11 .

In order to operate such an anaerobic glove box, a mixed gas of carbon dioxide and nitrogen gas is first supplied from the mixed gas cylinder 4 to the preliminary chamber 2 and mixed with the air in the preliminary chamber and the glove box 1 . When the oxygen concentration in the glove box 1 becomes 1% or less, the combination of the mixed gas is stopped and the circulation pump 10 is activated to circulate the gas in the preliminary chamber 2. At the same time, the electrochemical deoxidation device 3 The power switch is turned on and a DC voltage of 1.2 V is applied between the cathode 5 and the anode 6. By applying this DC voltage, oxygen is selectively consumed at the cathode 5 and oxygen is generated from the anode 6. This oxygen is discharged from the oxygen outlet 9 to the outside of the system. Thus, the oxygen concentration in the preliminary chamber 2 and the glove box 1 is 0.
It decreases to about 0.001%. When oxygen is consumed at the cathode 5, the pressure in the gas circulation system including the preliminary chamber 2 and the glove box 1 is reduced, but new air enters from the reduced pressure compensator 11 to compensate for this reduced pressure, and normal pressure is maintained. dripping This newly incoming oxygen in the air is also removed in the electrochemical deoxidizer 3. On the other hand, while the anaerobic glove box is in use, the voltage between the cathode 5 and anode 6 is always 1.2V.
DC voltage is applied).

In this way, if air enters the glove box or the preliminary chamber 2 from outside, the cathode 5 and anode 6
An electric current is passed between the two and automatically removes the invading oxygen.
As detailed above, the present invention eliminates the risks and operational complexity associated with the conventional use of hydrogen and palladium catalysts, and has extremely great industrial value.

[Brief explanation of the drawing]

FIG. 1 shows a schematic cross-sectional structure of an anaerobic glove box according to an embodiment of the present invention. 1... Glove box, 2... Preliminary room, 3... Electrochemical deoxidizer, 4... Mixed gas cylinder, 5... Cathode, 6...・・・Anode, 7...
...Electrolyte, 8...Gas chamber, 9...
・Oxygen outlet, 10...Circulation pump, 11...
...Decompression compensation device. Figure 1

Claims (1)

[Claims] 1. A glove having an electrochemical deoxidizing device consisting of an electrolytic cell consisting of a gas diffusion electrode capable of selective electrolytic reduction of oxygen as a cathode, an oxygen generating electrode as an anode, and sulfuric acid or a cation exchange membrane as an electrolyte, and a preliminary chamber. In an anaerobic glove box connected to a glove box, the air in the preliminary chamber and the glove box is replaced or replaced with carbon dioxide alone or a mixture of carbon dioxide and an inert gas. The electrochemical deoxidizer is activated to remove residual oxygen in the glovebox and prechamber, and the electrochemical deoxidizer is activated continuously while the anaerobic glovebox is in use to remove any residual oxygen from the outside. A method of operating an anaerobic glove box characterized by removing oxygen entering the glove box or reserve chamber.