Chemistry of inorganic compounds – Zeolite
Reexamination Certificate
1999-06-10
2001-10-09
Sample, David R (Department: 1755)
Chemistry of inorganic compounds
Zeolite
C423S712000
Reexamination Certificate
active
06299854
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention pertains to a method of producing artificial zeolite by heat treatment in the presence of water and an alkali of an inorganic component comprising silicic acid and aluminum, as well as a method of producing artificial zeolite by heat treatment in the presence of water and an alkali of a mixture that has been obtained by adding at least 1 or 2 or more of glass, diatomaceous earth and aluminum dross to an inorganic component comprising silicic acid and aluminum.
2. Description of the Related Art
In the past coal ash, particularly combustion ash or so-called fly ash, the fine powder that is produced when coal is burned by thermal power plants, etc., has been used as the starting material for artificial zeolite. This artificial zeolite has been produced by adding an aqueous 2 to 4 N alkali solution to the starting material and heat treating the product under atmospheric pressure. Therefore, the quality of the artificial zeolite that had been produced depended on the composition of the coal used as the starting material, and there were also limits in terms of this quality.
Moreover, synthesis of zeolite used for catalysts, which is called synthetic zeolite, is accomplished by performing a reaction at a high temperature of 100° C. or higher. In addition, since the production of zeolite is impeded if high-purity starting materials, including silicic acid and aluminum, are not used, starting materials of a low purity cannot be employed.
On the other hand, volcanic ejecta, such as effusive rock, volcanic ash, pumice, volcanic glass, etc., that is found around volcanoes cannot be used as an industrial starting material or on farmland and methods of using this volcanic ejecta pose problems in terms of efficient use of land.
Moreover, trash is being separated for disposal into several different types of trash and collected by municipalities throughout Japan. For example, this trash can be classified as trash that will burn, trash that will not burn, coarse trash, toxic trash, etc., and this classification method varies with the municipality. Of these, trash that will burn is generally incinerated in an incinerator, but treatment of the incineration ash becomes a problem. Moreover, of the trash that will not burn, some of the glass, metal, and synthetic resin is recycled, but treatment of synthetic resin products, including glass bottles, etc., metal cans, etc., synthetic resin trays, pet bottles, etc., is a problem.
Today the amount of waste discarded throughout Japan exceeds 50,000,000 tons and of this, approximately 85% is treated by incineration, crushing, recycling, etc. However, the amount of trash being reclaimed, including both the trash that is immediately reclaimed and the incineration ash from waste management facilities, is increasing annually. Consequently, much of this incineration ash, which is increasing annually, is being reclaimed and used on soil or being compacted in cement and discarded by each municipality, but it is difficult to guarantee a disposal site and this has become a significant social problem.
Furthermore, treatment of diatomaceous earth waste in industries that employ diatomaceous earth and treatment of the aluminum dross that is produced during smelting and refining in the field of aluminum smelting are industrial problems.
SUMMARY OF THE INVENTION
Consequently, the object has become to develop a method of producing artificial zeolite that is inexpensive and of uniform quality using as the starting material unused resources, such as descended pyroclastic materials, incineration ash, waste glass, waste diatomaceous earth, aluminum dross, etc.
The inventors performed various studies to accomplish this object and as a result, they were successful in presenting a method of producing artificial zeolite using an inorganic component comprising silicic acid and aluminum as the starting material. That is, the first of the present inventions is a method of producing artificial zeolite, characterized in that an inorganic component comprising silicic acid and aluminum is heat treated in the presence of water and an alkali. The preferred inorganic components containing silicic acid and aluminum are descended pyroclastic materials and incineration ash, and volcanic glass is particularly preferred as the descended pyroclastic materials. The preferred incineration ashes are incineration ash from combustible waste, the incineration ash from refuse-derived fuel, and coal ash. City trash and sludge are preferred examples of combustible waste. Sludge produced by dust removal during the process of recovering fibers after maceration of old paper (also called paper sludge) or activated sludge are particularly preferred. Sodium hydroxide and potassium hydroxide are the preferred alkalis, and an aqueous alkali solution is preferred for the water and alkali, with the ideal concentration being 2 to 4 N. Heat treatment should be performed at a temperature exceeding 100° C. particularly 120 to 230° C.
The second of the present inventions is a method of producing artificial zeolite, characterized in that a mixture that has been obtained by adding at least 1 or 2 or more of glass, diatomaceous earth and aluminum dross to an inorganic component comprising silicic acid and aluminum is heat treated in the presence of water and an alkali. The preferred inorganic components containing silicic acid and aluminum are descended pyroclastic materials and incineration ash, and volcanic glass is particularly preferred as the descended pyroclastic materials. The preferred incineration ashes are incineration ash from combustible waste, incineration ash from refuse-derived fuel, and coal ash. City trash and sludge are ideal examples of combustible waste. Sludge produced by dust removal during the process of recovering fibers after old paper has been macerated (also called paper sludge) or activated sludge are particularly preferred. Cullets of glass waste are the preferred glass. Sodium hydroxide and potassium hydroxide are the preferred alkalis, and an aqueous alkali solution is preferred for the water and alkali, with the ideal concentration being 2 to 4 N. Heat treatment should be performed at a temperature exceeding 100° C., particularly 120 to 230° C.
REFERENCES:
patent: 3694152 (1972-09-01), Sersale et al.
patent: 3714366 (1973-01-01), Fukuda et al.
patent: 3758539 (1973-09-01), Flank
patent: 3966883 (1976-06-01), Vaughan et al.
patent: 4661291 (1987-04-01), Yamasaki et al.
patent: 4935217 (1990-06-01), Simpson
patent: 5976244 (1999-11-01), Mallow
patent: 2408989 (1974-08-01), None
patent: 39 23 462 (1991-01-01), None
patent: 56-149313 (1981-11-01), None
patent: 64-24014 (1989-01-01), None
patent: 2-229709 (1990-09-01), None
patent: 3-45512 (1991-02-01), None
patent: 3-252310 (1991-11-01), None
patent: 04-012015 (1992-01-01), None
patent: 05155611 (1993-06-01), None
patent: 5-221628 (1993-08-01), None
patent: 6-64916 (1994-03-01), None
patent: 6-092624 (1994-04-01), None
patent: 6-239612 (1994-08-01), None
patent: 7-17757 (1995-01-01), None
patent: 7-196315 (1995-08-01), None
patent: 8-109015 (1996-04-01), None
patent: 10-296205 (1998-11-01), None
patent: 11-236212 (1999-08-01), None
patent: 712387 (1980-01-01), None
patent: 1407904 (1988-07-01), None
patent: 1432005 (1988-10-01), None
Ragimiv et al., “Preparation and Properties of New Zeolite L-D”, Inorg. Mater., vol. 14, No. 7, pp. 1045-1047, Dec. 1978.*
Lewis, Hawley's Condensed Chemical Dictionary, pp. 365-366 & 1035, 1993.*
Summary of a thesis written by a present inventor in 1989. pp. 143-149. (English translation of Summary only). (No month).
Relevant portion of a thesis written by a present inventor in 1994. pp. 53-70 (w/English translation). (no month).
Henmi Teruo
Sakagami Etsuro
Armstrong Westerman Hattori McLeland & Naughton LLP
Sample David R
LandOfFree
Method of producing artificial zeolite does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of producing artificial zeolite, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of producing artificial zeolite will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2611427