JPS60262985A - Alkali metal composition aqueous solution and supplying method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION INDUSTRIAL APPLICATION This invention relates generally to molten salt bath replenishment materials, and more particularly to materials that are added as an aqueous solution to an anhydrous molten salt bath by spraying.

Prior Art U.S. Pat. No. 4,113,511 discloses that an aqueous solution of several chemicals is sprayed onto a bath surface of said chemicals by an atomization process before the sprayed composition impinges on the bath surface. 1 teaches that the chemical can be added to an anhydrous molten salt bath in droplets of sufficient size to trap the water in it.

U.S. Pat. No. 4,273,591 discloses an apparatus useful for performing such spray additions of aqueous solutions of chemicals to anhydrous molten salt baths.

However, to date, many of the aqueous solutions of alkali metal hydroxides and alkali metal nitrates used in metal treatments such as descaling have caused various problems, which have prevented their use in the aforementioned treatment methods and equipment. is considered undesirable.

SUMMARY OF THE INVENTION It is therefore highly desirable to provide a balanced and stable aqueous solution of replenisher that remains in solution and can be sprayed evenly and consistently under working conditions in an industrial environment. was. This is especially necessary when preparing aqueous make-up solutions for anhydrous molten bath salts containing alkali metal salts.

It is therefore an object of the present invention to provide an aqueous replenishment solution that meets the above-mentioned requirements.

According to the present invention, an aqueous substance containing an alkali metal nitrate and an alkali metal hydroxide which is very suitable as a replenisher for an anhydrous molten salt bath for metal processing baths is provided. It has been found that a substantially saturated homogeneous aqueous solution can be obtained. In this case, the solution Vi is liquid at 50°C, has a viscosity low enough to form droplets when sprayed through a nozzle, and does not form any precipitate between 50°C and 110°C. The bath may also contain other substances such as chlorides and permanganates.

EMBODIMENTS In carrying out the present invention to replenish alkali metal hydroxides and alkali metal nitrates to an anhydrous molten metal processing bath as described in the aforementioned U.S. Pat. It has been found that it is highly desirable to have reliable range aqueous pressure control of the replenisher with very well defined characteristics. Controlling the properties of supply materials
as well as providing a more industrially economical method of replenishment.
Undesirable deposits, nozzle blockage, harmful excess moisture,
Adverse effects such as component imbalance are reduced or eliminated.

For working with alkali metal hydroxide-alkali metal nitrate systems, it has been found to be most advantageous to use saturated aqueous solutions of alkali metal nitrates and alkali metal hydroxides. Since K is sprayed in droplets through a nozzle and is liquid at 50°C, the solution must have a sufficiently low viscosity.

Furthermore, it must not produce any precipitates between 50°C and 110°C. As used herein, the term "substantially saturated solution" means a substance or substances with the least solubility in a substantially saturated amount in water at the desired temperature as a function of which the remaining substances are present in saturated amounts. means less. To determine this, it is necessary to determine the proportion of the mass of the substance that does not take into account water (water of crystallization is included). Once this value has been determined, just enough water is added to completely dissolve the smallest soluble component and the composition is
Check to see if it is liquid at ℃. In this way, the additive has a viscosity low enough to be sprayed in small droplets and does not form any precipitate between 50°C and 110°C.

Displayed below are some examples of aqueous solutions containing alkali metal hydroxides and alkali metal nitrates, some of which also include chlorides and permanganates.

55% water 15 nitrate 30 t Sodium hydroxide 100 chi 53.6ch water 300 t Sodium hydroxide 150 t Sodium nitrate 1.4% potassium hydroxide 100.0ch 57chi water 30.0chi Sodium hydroxide 3.6 t Potassium hydroxide 6.4 Sodium nitrate 3.0 t Sodium chloride 100.0ch B0.0% water 31.4% Potassium hydroxide* 8.4 Sodium nitrate 0.2 t Potassium permanganate 1000% 55.0ch water 216 Sodium hydroxide 21.2 Sodium nitrate 2.2 Sodium chloride 100,. 0% Example ■ 55.0ch water 27.6 Sodium hydroxide 13.0chi Sodium nitrate 1.4% Potassium hydroxide* 3.0 t Sodium chloride ioo, ochi *Based on industrial KOH with a purity of approximately 85%.

The saturation levels of various replenishers are shown below.

Example I Sodium nitrate was saturated in the presence of caustic soda.

Example 2 Sodium nitrate was saturated in the presence of a larger amount of hydroxide than above.

Example 2 Sodium nitrate and sodium chloride were saturated in the presence of larger amounts of sodium hydroxide and potassium hydroxide than above.

Nitrate (N,
, -) was saturated.

Example V Sodium chloride and sodium nitrate were saturated in the presence of sodium hydroxide.

Nitrate (N, -) and chloride (C1-) were saturated in the presence of larger amounts of sodium hydroxide and potassium hydroxide.

It should be noted that many substances are ionized in aqueous solutions, so the determination of saturation is based on the concentration at which these ions form precipitates.

The aqueous solutions used in each of the above examples had an orifice diameter of 0.
Using a 4572 m (0,018") nozzle, it can be easily sprayed at 50° C. without clogging.

Agent Patent Attorney Takeo Goto Agent Patent Attorney Isao Fujimoto Agent Patent Attorney Akebono Akebono Procedural Amendment (Method) % Formula % 1. Indication of the case 1982 Patent Application No. 114696 2. Name of the invention Alkaline Metal composition aqueous solution and its replenishment method 6, relationship with the case of the person making the amendment Patent applicant address (residence) 48225, Minnesota, United States of America
Detroit Westwood Avenue +289
0 Name (Name) Korinsha Corporation/Yon 5 Date of amendment order (Date of dispatch) September 25, 1980 6 Subject of amendment (Representative of the patent applicant in the letter of attorney (2) application) (5) Full text of the specification Z Contents of the amendment (li As per the attached sheet (2) As per the attached application (6) Engraving of the description (no change in contents) B, List of attached documents (li) Application for amendment 1 copy (2) 1 copy of power of attorney and its translation (4) 1 copy of statement of reasons

Claims (16)

[Claims] (1) a substantially saturated aqueous solution containing at least one alkali metal hydroxide and at least one alkali metal nitrate and having a viscosity sufficient to be sprayed to form a large number of droplets; an alkali metal which is stable between 50° C. and 110° C. and does not form precipitates; can be replenished by spraying into a molten salt bath of the corresponding composition when the aqueous solution does not contain water; Composition aqueous solution. (2) The alkali metal composition aqueous solution according to claim 1, wherein the aqueous solution substantially consists of sodium nitrate, sodium hydroxide, and water. (3) The aqueous solution contains about 15% sodium nitrate and about 3% sodium nitrate.
The alkali metal composition aqueous solution according to claim 2, which comprises 0 ton of sodium hydroxide and the remainder water. (4) The alkali metal composition aqueous solution according to claim 1, wherein the aqueous solution consists essentially of sodium hydroxide, sodium nitrate, sodium chloride, and water. (5) The alkali according to claim 4, wherein the aqueous solution comprises about 21.6% sodium hydroxide, 21.1% sodium nitrate, 22% sodium chloride, and the balance water. Metal composition aqueous solution. (6) The alkali metal composition aqueous solution according to claim 1, wherein the aqueous solution consists essentially of sodium hydroxide, sodium nitrate, potassium hydroxide, and the balance is water. (7) Claim 6, wherein the aqueous solution comprises about 30.0% sodium hydroxide, about 15.0% sodium nitrate, about 1.4% potassium hydroxide, and the balance water.
The aqueous alkali metal composition solution described in 2. (8) the aqueous solution substantially contains sodium hydroxide, potassium hydroxide, sodium nitrate, and thorium chloride;
The alkali metal composition aqueous solution according to claim 1, wherein the remainder is water. (9) The aqueous solution consists of about 30.0% sodium hydroxide, about 36% potassium hydroxide, about 64% sodium nitrate, about 30% sodium chloride, and the balance is water. An aqueous alkali metal composition solution according to claim 8. (10) A patent claim in which the aqueous solution comprises about 27.6% sodium hydroxide, about 14% potassium hydroxide, about 13D-sodium nitrate, about 30% sodium chloride, and the balance water. The aqueous alkali metal composition solution according to item 8. (11) The alkali metal composition aqueous solution according to claim 1, wherein the aqueous solution essentially consists of potassium hydroxide, sodium nitrate, potassium permanganate, and water. (12) The aqueous solution of claim 11, wherein the aqueous solution has about 31.4% potassium hydroxide, about 8.4% sodium nitrate, and about 0.2% potassium permanganate. Alkali metal composition aqueous solution. (13) The alkali metal composition aqueous solution according to claim 1, wherein the alkali metal contains both potassium and sodium. (14) The alkali metal composition aqueous solution according to claim 1, wherein the aqueous solution contains at least one alkali metal chloride. (15) The aqueous alkali metal composition solution according to claim 1, wherein the aqueous solution contains at least one alkali metal permanganate. (16) A method for replenishing an alkali metal composition into an anhydrous molten salt bath comprising: preparing a saturated aqueous solution of the alkali metal composition; and spraying the aqueous solution onto the anhydrous molten salt bath. A method for replenishing an aqueous solution of an alkali metal composition, comprising the steps of: