JPS6310786B2 - - Google Patents

Description

Detailed Description of the Invention The present invention provides a water hardness determination method for determining whether or not soft water produced from natural water, tap water, blown water from steam cans, etc. has a desired hardness. Regarding medicine.

Eriochrome Black T, Chalcon, which is added to the raw water that is the target of water hardness determination.
Color-forming indicators such as N-N indicators have the property of causing a hue change depending on the presence or absence of hardness components only when the pH value of the raw water is within a certain range. Chelating agents such as ethylenediaminetetraacetic acid that are added to raw water to react with hardness components tend to react not only with hardness components but also with iron ions contained in raw water, causing a change in the hue of the color indicator. Since the chelating agent is titrated to 100% and the hardness is determined based on the titrated amount of the chelating agent, it is necessary to ensure that iron ions and the like do not react with the chelating agent.

Therefore, when determining the hardness of water, in addition to a coloring indicator, liquids such as a PH value adjusting agent to adjust the PH value of raw water to within a certain range, and an impregnating agent to absorb iron ions, etc., must be used in advance. It must be placed in raw water.

These color indicators, PH adjusters, and impregnation agents must be added to the raw water at a predetermined mixing ratio, but conventionally, when determining hardness, the above-mentioned chemical solutions are added while adjusting the mix individually each time, and then dispersed. It is necessary to carry out judgment or quantitative analysis after stirring for the purpose of dispersion, which poses a problem in that it requires a great deal of time and effort to adjust the formulation of each chemical solution and to stir it.

That is, the above-mentioned chemical solution is adjusted in advance at a predetermined mixing ratio,
The above problem can be solved by mixing this with water or alcohol as a solution and storing it, and then adding this mixed solution into the raw water when determining hardness. Both aqueous and alcoholic solutions of Eriochrome Black T, chalcone, N-N indicators, etc., are unstable and cannot be stored for long periods of time. Because you can't.

Therefore, it is known that triethanolamine can be stored for a long period of time if used as a solvent (for example, see Keihei Ueno's "Chelate Commercial Law" Nankodo), but triethanolamine becomes more viscous when the temperature drops. However, there are problems in that it is difficult to handle, such as the operation of adding it to raw water is troublesome, and the dispersibility into raw water is poor, so it is necessary to carefully stir it.

In addition, Eriochrome Black T is used as a color indicator.
It is also known that when a polyhydric alcohol, particularly a polyglycol, is used as a solvent, it exhibits remarkable stability even when exposed to direct sunlight and air (see, for example, Japanese Patent Publication No. 6832/1983). ),
A solution using this polyhydric alcohol has a high viscosity and is difficult to handle, just like the solution using triethanolamine mentioned above, and the polyhydric alcohol itself simply functions as a solvent to maintain the stability of the color indicator. However, since it cannot exhibit any useful function in determining hardness, it becomes a factor that increases the manufacturing cost compared to water as a solvent.

Furthermore, in order to avoid the inconveniences that would occur if a color indicator solution was used as described above, each drug should be prepared in powder form beforehand, and then added to the raw water and stirred and dissolved each time the hardness was determined. However, in order to dissolve the powdered drug in the raw water, sufficient stirring was required, and the process was time-consuming and could not be of any use.

In view of the above points, the present invention has been developed to make a determination drug into an aqueous solution through a rational formulation, which has good diffusivity and can be easily stirred, and also enables stable coloring over a long period of time. The purpose of the present invention is to provide a device that allows easy, reliable, and quick hardness determination.

The characteristic constitution of the water hardness determining agent according to the present invention for achieving the above object is 1-(1-hydroxy-
5-50% by weight of triethanolamine in an aqueous solution containing 0.01-1.0% by weight of 4-methyl-2-phenolazo)-2-naphthol-4-sulfonic acid.
and 0.05 to 20% by weight of an acid or its salt that is colorless in water and does not form salts insoluble with the hardness component to form an aqueous solution with a pH of 9.1 to 11.4. It has an effect.

That is, the present inventor has discovered that 1-
(1-Hydroxy-4-methyl-2-phenolazo)-2-naphthol-4-sulfonic acid (hereinafter abbreviated as Karmagide) is relatively stable in water, and as a component of the solvent. Focusing on the fact that using triethanolamine not only stabilizes Karma Guide, but also has the effect of destroying iron ions contained in raw water, we did not simply use triethanolamine as the solvent for Karma Guide. Since Karma Guide is made into an aqueous solution and triethanolamine is blended into this aqueous solution, it has less viscosity than a solution that uses triethanolamine alone as a solvent, and can be easily added to raw water. The dispersibility was also improved, and the stirring operation was made easier, making handling extremely easy.

In addition, triethanolamine itself not only has the function of stabilizing Karma Guide, but also has the function of stabilizing Karma Guide.
Because it has the ability to absorb iron ions, etc. in raw water, it is possible to reduce or eliminate the amount of impregnating agent, which is an essential compounding agent when using polyhydric alcohol as a solvent, and the total amount of it as a solvent. Since water is added instead of using triethanolamine, overall there is less wasted material and manufacturing costs can be lowered.

Therefore, an aqueous solution of Karma Guide as a coloring indicator, triethanolamine as an anti-inflammatory agent and agent for maintaining the stability of the compounded solution, a hardness component as a pH adjuster, and an acid or its salt that does not form an insoluble salt. By rationally combining these, it is possible to stabilize KarmaGuide as a color indicator over a long period of time, while it is extremely easy to handle and there is little waste in the drug formulation itself. ,
Therefore, it has now become possible to provide a water hardness determining agent that can be manufactured at low cost.

The following embodiments of the present invention will be described in detail.

In an aqueous solution containing 0.01 to 1.0% by weight of 1-(1-hydroxy-4-methyl-2-phenolazo)-2-naphthol-4-sulfonic acid, impede against interfering ions and adjust the viscosity of the blended liquid. Contains 5-50% by weight of triethanolamine as a drug to stabilize the coloration for long-term determination, and 0.05-20% by weight of boric acid or its salt, which does not form salts that are insoluble with hardness components, as a pH adjuster. Then, it is made into an aqueous solution with a pH of 9.1 to 11.4 to produce a water hardness determining agent.

The above determination agent is applied to all types of water produced from natural water or tap water, such as soft water with a pH of 4 to 12 or blown water from steam cans, and is colored blue if it has the desired hardness, and blue in other cases. The hardness is determined by coloring red.

In addition, the boric acid used as the above-mentioned PH adjuster has the property of not forming an insoluble salt in water with the hardness component, and being colorless in water. Alternatively, it is also possible to apply a salt thereof in place of boric acid.

In addition, when manufacturing the determination drug, sodium sulfide 0.1
Up to 10% by weight may be added, which has the advantage that even if copper and zinc exist as interfering ions in the water to be evaluated, a higher effectiveness can be achieved.

In an experiment using Eriochrome Black T as a coloring indicator for conventional hardness determination,
Stable coloring occurs only for about 10 minutes after coloring,
On the other hand, when the hardness determination film of the present invention was used, stable coloring was achieved over several hours to several days, and it was clear that the present invention was extremely superior in terms of coloring stability.

The drawing shows an infusion bottle containing the hardness determining drug of the present invention, in which a mouth member 4 having a tapered injection port 3 is fitted into the bottom 2 of a container body 1 made of synthetic resin, and the container body 1 is A lid 6 is attached to and detached from a screw part 5 formed in the bottom part 2 of the container, and the container body 1 is compressed and a fixed amount can be easily dripped into the water to be evaluated during hardness determination. There is.

The hardness determination agent of the present invention can also be applied to total hardness quantitative analysis by EDTA titration and hardness determination by automatic colorimetry.

[Brief explanation of the drawing]

The drawing is a sectional view of a drip bottle for accommodating a hardness determining drug according to the present invention.

Claims (1)

[Claims] 1 1-(1-hydroxy-4-methyl-2-
In an aqueous solution containing 0.01 to 1.0% by weight of triethanolamine (phenolazo)-2-naphthol-4-sulfonic acid, add 5 to 50% by weight of triethanolamine and an acid that is colorless in water and does not form a salt insoluble with the hardness component. PH9.1-11.4 by blending 0.05-20% by weight of the salt
A water hardness determination drug that is made into an aqueous solution.