Anion adsorbing carbon material, as well as manufacturing method and manufacturing facilities for same

Abstract

This invention provides an anion adsorbing carbon material which is inexpensive, environmentally friendly and excellent in the anion adsorption, as well as a manufacturing method and a manufacturing facilities for the same. This invention is characterized in that a raw material which comprises plant(s) is contacted with a solution including calcium ions, and after that, carbonized, and subsequently, contacted with an acid solution.

Description

TECHNICAL FIELD [0001] This invention relates to an anion adsorption carbon material for adsorbing anions such as nitrate ions and fluoride ions, as well as a manufacturing method and a manufacturing facilities for the same. BACKGROUND ART [0002] Contamination of a water quality and soil by heavy metals, agricultural chemicals and an organochlorine compounds has become a problem in that it destroys the environment. Though these harmful substances can be adsorbed and removed with adsorbents such as activated carbon and a zeolite, it is presently difficult to treat nitrate nitrogen, nitrite nitrogen, fluorine, arsenic and cyan which exist in the form of anions with adsorbents. [0003] That is to say, nitrate nitrogen and nitrite nitrogen are included in fertilizers used in tea fields, turfs for golfing and the like, and have become a factor in ground water contamination, which is presently a large problem. This is because nitrate ions and nitrite ions have negative charge and do not be...

AI Technical Summary

Benefits of technology

"The invention provides an anion adsorbing carbon material that is inexpensive, environmentally friendly, and has excellent anion adsorption ability. The material is made by contacting a solution containing calcium ions with a raw material made of plant(s) and then carbonizing it. The resulting material can be used to remove anions such as nitrate and fluorine from wastewater and soil. The method is simple and cost-effective. The invention solves the problem of contamination caused by anions such as nitrate and fluorine, which are difficult to remove with traditional methods."

Problems solved by technology

Contamination of a water quality and soil by heavy metals, agricultural chemicals and an organochlorine compounds has become a problem in that it destroys the environment.

Though these harmful substances can be adsorbed and removed with adsorbents such as activated carbon and a zeolite, it is presently difficult to treat nitrate nitrogen, nitrite nitrogen, fluorine, arsenic and cyan which exist in the form of anions with adsorbents.

That is to say, nitrate nitrogen and nitrite nitrogen are included in fertilizers used in tea fields, turfs for golfing and the like, and have become a factor in ground water contamination, which is presently a large problem.

Thus, though measures against the above described problem are r there are limitations, such that anaerobic conditions are required in biological treatment where, for example, denitrifying bacteria are used to remove nitrate ions and nitrite ions, and in addition, there are similar limitations with other methods, and no effective measures have been found.

In addition, fluorine is included in wastewater from semiconductor factories, glass factories, plating factories and the like, and though a method for adding calcium compounds to fluorine in industrial wastewater so that the fluorine can be removed in the form of calcium fluorine is used, further installation of adsorption towers having an anion exchange resin for active alumina and fluorine is required, raising the cost.

In addition, expensive dedicated anion exchange resins are required in order to meet the Japanese environmental standard of 0.8 mg / L.

Furthermore, expensive anion exchange resins are separately required for treating arsenic, cyan and the like, which are included in industrial wastewater and ground water.

As described above, no inexpensive material for adsorbing anions including nitrate ions as that described above have been found at present, and therefore, contamination by these anions tends to sped, and once the environment is contaminated by anions as described above, high cost becomes necessary to restore it.

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