EP0435176A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Neutralizing and anti-acidifying agents and their manufacture
Assignee: 5 SENCES CO., LTD.
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Filing: 1990-12-20
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Granted: —
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Expires: 2010-12-20
Abstract
Abstract The invention provides a neutralizing and anti-acidifying agent composed of a porous substance including silicon dioxide as a carrier and a metal oxide or oxides which act as a base in an acidic medium and are supported on silicon dioxide; in which the metal oxide and silicon dioxide form a complex salt. The safe and non-corrosive agent of the invention efficiently neutralizes acidic waste water without producing undesirable deposits and prevents acidification of waste water to maintain the waste water neutral. The invention also provides process for manufacturing the agent. It includes the steps of: wet mixing silicon dioxide with a metal oxide or oxides acting as a base in an acidic medium; leaving the mixture at ambient temperature to make it sufficiently hard; pressure crystallizing the mixture; and firing the crystallized mixture. The agent is manufactured efficiently and cheaply according to the process.
Inventors
- 👤 Seietsu Ichiba
- 👤 Masakazu Wakahara
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 08:57
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/66
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
55 words
A neutralizing and anti-acidifying agent in the form of a porous substance comprising: a) silicon dioxide acting as a carrier; and, b) a metal oxide which acts as base in an acidic medium are supported on said silicon dioxide; in which, c) said metal oxide and said silicon dioxide combine to form a complex salt.
Claim 2
Dependent Claim
41 words
A neutralizing and anti-acidifying agent as claimed in claim 1 wherein: said metal oxide is selected from a group consisting of basic oxides including calcium oxide, iron oxide, manganese oxide, magnesium oxide, and potassium oxide, and amphoteric oxides including aluminum oxide.
Claim 3
Dependent Claim
32 words
A neutralizing and anti-acidifying agent as claimed in claim 1, wherein: a) said metal oxide is calcium oxide; and, b) said complex salt is tobermorite composed of silicon dioxide and calcium oxide.
Claim 4
Dependent Claim
40 words
A neutralizing and anti-acidifying agent as claimed in claim 1, wherein: said metal oxide comprises calcium oxide and at least one other oxide selected from the group consisting of aluminum oxide, iron oxide, manganese oxide, magnesium oxide, and potassium oxide.
Claim 5
Dependent Claim
15 words
A neutralizing and anti-acidifying agent as claimed in claim 1 and further comprising aluminum powder.
Claim 6
Dependent Claim
18 words
A neutralizing and anti-acidifying agent as claimed in claim 1, wherein said metal oxide is iron (III) oxide.
Claim 7
Dependent Claim
63 words
A manufacturing process for manufacturing a neutralizing and anti-acidifying agent comprising the steps of: a) wet mixing silicon dioxide with a metal oxide which acts as base in an acidic medium; b) leaving the mixture at ambient temperature for a period sufficient for it to dry to a hardness sufficient for working; c) pressure crystallizing the mixture; and, d) firing the crystallized mixture.
Claim 8
Dependent Claim
37 words
The manufacturing process as claimed in claim 7 and additionally including the step of: first selecting the metal oxide from a group consisting of calcium oxide, iron oxide, manganese oxide, magnesium oxide, potassium oxide, and aluminum oxide.
Claim 9
Dependent Claim
31 words
The manufacturing process as claimed in claim 7 wherein the steps thereof include the step of hardening the mixture of the metal oxide and silicon dioxide by hydration at ambient temperatures.
Claim 10
Dependent Claim
27 words
The manufacturing process as claimed in claim 7 wherein said step of firing the crystallized mixture comprises firing the mixture at a temperature not greater than 650°C.
Claim 11
Dependent Claim
63 words
The manufacturing process as claimed in claim 7 wherein said step of firing the crystallized mixture comprises: a) firing the mixture in a firing furnace; b) raising the temperature in the furnace at a rate of not greater than 30°C/hour to 200°C; and c) raising the temperature in the furnace at a rate of not greater than 50°C/hour to an ultimate firing temperature.
Claim 12
Dependent Claim
29 words
The manufacturing process as claimed in claim 7 wherein the steps thereof include the step of pressure crystallizing the mixture at 10 atmospheric pressures and 180°C for 24 hours.
Claim 13
Dependent Claim
35 words
The manufacturing process as claimed in claim 7 and further comprising the steps of: a) crushing a fired block into small grains; and, b) classifying the grains by sizes to select those of appropriate size.
Claim 14
Dependent Claim
23 words
The manufacturing process as claimed in claim 16 wherein the steps thereof include the step of mixing a binder with the small grains.
Claim 15
Dependent Claim
30 words
The manufacturing process as claimed in claim 18 wherein the steps thereof include the step of selecting the binder from the group consisting of ethylene glycol and paraffin-containing stearic acid.
Claim 16
Dependent Claim
78 words
A process for manufacturing a neutralizing and anti-acidifying agent comprising the steps of: a) mixing calcium silicate with aluminum powder and a metal oxide to form a mixture; b) adding an appropriate amount of water to the mixture and mixing so as to form a well stirred slurry; c) allowing the slurry to stand at ambient temperature until sufficiently hard enough to be pressure crystallized; d) pressure crystallizing the hardened slurry mixture; and, e) firing the crystallized mixture.
References Cited (Backward Citations)
FR2615755A1
Cited
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