Electrochemical Method for Producing and Storing Hydrogen by the Redox of Zinc and Water

Abstract

Disclosed herein is an electrochemical method for producing and storing hydrogen, which is a closed system consisting of a gas-generating electrode, an electrolyte and a zinc electrode, the gas-generating electrode and zinc electrode are connected respectively to the external circuits; characterized in that switching on the external circuit of the gas-generating electrode and zinc electrode the hydrogen is to be released, the reduction reaction of water occurs on the gas-generating electrode producing hydrogen; zinc is oxidized on the zinc electrode generating the oxidation products of zinc; when the hydrogen is to be stored, supplementary water is supplied to the closed system, the negative pole of power source is connected to the external circuit of the zinc electrode, and the positive pole of power source is connected to the external circuit of the gas-generating electrode, switching on the direct current, the reduction reaction of zinc occurs on the zinc electrode, the oxidation products of zinc are reduced into zinc, renew the zinc electrode, the oxidation reaction of water occurs on the gas-generating electrode, the oxygen is generated and discharged. A simple and convenient process and widely applied are property of the present invention. It suits to provide hydrogen for hydrogen fuel cells. While providing the hydrogen, it can also generate electricity as secondary product, which generates the electricity together with a fuel cell.

Description

FIELD OF THE INVENTION[0001]This invention relates to the technology of producing and storing hydrogen, particularly to the electrochemical method for producing and storing hydrogen by the redox of zinc and water.BACKGROUND OF THE INVENTION[0002]As consumption of petrochemical fuel and exhaustion of reserves of petrochemical fuel are daily on the increase, environmental protection has been gradually emphasized. Primary energy source including petroleum, coal and natural gas shall be finally replaced by clean and renewable energy source such as solar energy, wind energy, energy from the sea, biological energy, etc. As secondary energy source, without pollution, hydrogen energy is greatly valued by every country in the world due to considerable advantages of being rich in its resource, having high combustion heat quantity, producing water as its combustion product, and having no environmental pollution, etc. Especially, a hydrogen-oxygen (air) fuel cell that uses hydrogen as its fuel,...

AI Technical Summary

Benefits of technology

[0003]The objective of the invention is to provide the electrochemical method for producing and storing hydrogen by the redox of zinc and water with high reliability, low cost, simple and convenient process wherein the zinc electrode can be used repeatedly.

Problems solved by technology

Main cause of hindering its popularization is lack of appropriate source of hydrogen.

Wherein, the high-pressure hydrogen bottle method and the low temperature fluidized method have some serious shortcomings such as high cost, being poor in the aspect of safety etc.

The hydrocarbon fuel reforming method, being poor in the aspect of purity of hydrogen gas, needs the relatively high temperature, the large equipment.

However, the storing-hydrogen alloy is very expensive and easy to become chalking in the course of filling, which is relatively complicated, and releasing the hydrogen gas.

However, its shortcomings are as follows: the aluminum alloy electrode is a disposable consumable material; it is needed to replace the aluminum alloy electrode after hydrogen generation every time; it has a high consumption; in addition, produced aluminum oxide must be eliminated by pump circulation filtering, and the hydrogen generation course is relatively complicated, which increases the cost.