JPS5841353B2 - Bouseizai - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the suppression of corrosion of metals, and specifically relates to a compounding agent added to a metal corrosive liquid such as water or seawater in order to suppress corrosion of metals. be.

When water is recycled or stored, for example as cooling water, dissolved ions typically increase.
Furthermore, as is well known, seawater contains a wide variety of dissolved ions.

Therefore, common metal materials that come into contact with water, seawater, etc. are easily corroded, causing various problems.

Therefore, in order to prevent corrosion and rust of these metal materials, coatings with corrosion-resistant materials or various anti-corrosion and rust preventive agents have been developed and used.

By the way, these anti-corrosion and rust preventive agents require only a small amount to be added when used, do not easily react with components such as water or seawater with a large amount of dissolved ions, and do not reduce their effectiveness, and do not cause secondary aggregation. It is necessary that the additive be easily dissolved and dispersed, or that it be a liquid additive in order to allow continuous addition, for example.

Furthermore, from the standpoint of preventing water pollution, consideration must be given to ensuring that these additives do not contain harmful metals such as chromium, do not contain a high degree of phosphorus, and have low toxicity.

1.3.5-1-IJ, (hydroxyalkyl)hexahydrotriazine is already known to have the effect of suppressing corrosion of metals and preventing rust in the aqueous phase and oil phase. In water containing a lot of water, especially seawater, it has almost no effect on inhibiting corrosion or rust on metals.

However, we found that this l. 3.5-Hsu(
It has been found that by converting hydroxyalkyl (hydroxyalkyl)hexahydrotriazine into a phosphate salt, it has a remarkable anticorrosion and rust-preventing effect on water containing many dissolved ions, especially seawater.

That is, the compound of the active ingredient of the present invention is represented by the following general formula.

This 1,3.5-1 lith(hydroxyalkyl)hexahydrotriazine phosphate is unique due to the amount of phosphoric acid.
It may be either a species of phosphate or a mixture of two or three phosphates.

As described in the Examples, the amount added may be smaller than that of conventional corrosion and rust preventive agents.

In addition, it is an additive that does not react with water or seawater containing a large amount of dissolved ions, and does not cause secondary aggregation.

Furthermore, although the active ingredient substance of the present invention is a viscous liquid substance, it can be dissolved in water at any ratio, and therefore can be easily used as an aqueous solution of any content depending on the handling method.

In addition, due to the difficulty of wastewater treatment of water or seawater to which the rust preventive of the present invention has been added, there is almost no difference in effectiveness even if the amount of phosphoric acid is adjusted appropriately.

The active ingredient of the present invention is an odorless compound that can be easily obtained as an aqueous solution, as described in the following examples.

Synthesis Example 1 To 183 g of monoethanolamine, 102 g of 88φ rose formaldehyde is added at 50 to 60°C, and after reacting at the same temperature for 2 hours, 240 g of water is added.

After cooling and adding 110 g of 89 polyphosphoric acid at 20-30°C, 635 g of 50 polyphosphoric acid solution of 1,3.5-tris(hydroxyethyl)hexahydrotriazine/monophosphoric acid is obtained.

Synthesis Example 2 102 g of 88φ paraformaldehyde is added to 228 g of isopropanolamine at 50 to 70°C, and after reaction for 2 hours at the same temperature, 239 g of water is added.

When 55 g of 89φ phosphoric acid is added at 20 to 30°C, 1
．． 624 g of a 50% solution of a mixture of 1/3 and 2/3 phosphates of 3.5-tris(2-hydroxypropyl)hexahydrotriazine are obtained.

The present invention will be explained below with reference to Examples.

Example JIS-G-3310 steel plate (8crfL×6crIL)
JIS-Z-2 to calculate the number of rust occurrences in seawater using
Measure according to 912.

The additive symbols in the table of results indicate the following compounds.

As mentioned above, as long as the added amount is 115 to 1/10 of that of conventional rust inhibitors, the effect remains the same, and as long as it does not react with conventional rust inhibitors, there is no problem in using it in conjunction with existing conventional rust inhibitors. , it became clear that there was actually a mutual effect.

Claims (1)

[Scope of Claims] 1, 3 represented by the general formula 1 (wherein R'JR2, R3 represent a hydroxyalkyl group having 2 to 8 carbon atoms, and n represents an integer of 1.2 or 3) A metal rust inhibitor containing 5-Hs(hydroxyalkyl)hexahydro l-IJ azine phosphate as an active ingredient.