JP2010059444A - Detergent for iron plate and method for cleaning the iron plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detergent for an iron plate which exhibits satisfactory detergency even when the liquid temperature of a cleaning liquid is lower than 60°C, and can reduce the amount of carbon dioxide discharged from an iron mill. <P>SOLUTION: The detergent includes: a composition obtained by beforehand mixing at least the grains of a semiconductor, peroxide and/or carbonate and an active accelerator being at least one kind selected from the group consisting of a sodium compound, inorganic acid and organic acid; an alkaline substance; and a nonionic or anionic surfactant. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cleaning agent for iron plates and a method for cleaning iron plates.

Conventionally, cleaning of mineral oil or the like adhering to the surface of an iron plate such as a cold-rolled steel plate has been performed with an alkaline substance such as sodium hydroxide or sodium orthosilicate. (See Patent Document 1).
However, in conventional cleaning, a cleaning solution containing an alkaline substance is used as steam or hot water of about 70 ° C. to 90 ° C., so that a lot of energy is required to produce these cleaning steam and hot water, and as a result There was a problem that the amount of carbon dioxide emissions from steelworks increased. In recent years, this has become a problem that cannot be ignored for steelworks that are required to reduce carbon dioxide emissions.

In addition, since mineral oil and the like adhering to the surface of the iron plate has a high viscosity, the conventional surfactant type cannot sufficiently clean these oils, and the surfactant has a detergency. Increasing the amount of added causes a problem that it becomes difficult to treat the waste liquid after washing.
Japanese Patent No. 3706478

  The present invention has been made in view of the above-described conventional problems, and exhibits good cleaning power even when the temperature of the cleaning liquid is less than 60 ° C., and the temperature of the cleaning liquid can be reduced, so that it can be discharged from the steelworks. An object of the present invention is to provide an iron plate cleaning agent and a method for cleaning an iron plate that can reduce the amount of carbon dioxide produced.

In order to achieve the above object, the iron plate cleaner according to the present invention is at least one selected from the group consisting of semiconductor particles, peroxides and / or carbonates, sodium compounds, inorganic acids, and organic acids. The composition obtained by mixing at least an activity promoter in advance, an alkaline substance, and a nonionic or anionic surfactant is contained.

  Here, the semiconductor used in the iron plate cleaner of the present invention is not particularly limited, and examples thereof include oxides such as titanium, zinc, vanadium, bismuth, tungsten, and iron, strontium titanate, and cadmium sulfide. Of these, oxides of titanium, vanadium, and iron are preferable, and titanium dioxide is more preferable because it is inexpensive and has a stable cleaning effect. Furthermore, when using titanium dioxide, it is preferable to use a rutile type from the viewpoint of reaction stability with peroxide and / or carbonate.

Although it does not specifically limit as a peroxide used in the cleaning agent for iron plates of this invention, For example, hydrogen peroxide solution, sodium percarbonate, sodium perborate etc. are mentioned.
The carbonate used in the iron plate cleaner of the present invention is not particularly limited, and examples thereof include sodium orthosilicate, sodium metasilicate, sodium carbonate, sodium bicarbonate, sesquicarbonate, sodium sulfate and the like. Any one or more of these peroxides and / or carbonates can be used.
Of these peroxides and / or carbonates, it is preferable to use peroxides when emphasizing cleaning performance. Emphasis is placed on environmental aspects such as safety and wastewater treatment when attached to the skin. In some cases, it is preferable to use carbonate. Moreover, when using a peroxide, it is preferable to use sodium percarbonate from the point that activation effects, such as electronic excitation of a semiconductor, are high.

  Although it does not specifically limit as a sodium compound used in the cleaning agent for iron plates of this invention, For example, phosphates, such as sodium tripolyphosphate, silicates, such as sodium orthosilicate, are mention | raise | lifted. In order to further improve the cleaning effect, it is preferable to use phosphate and silicate simultaneously.

  The organic acid used in the iron plate cleaner of the present invention is not particularly limited, and examples thereof include acetic acid and citric acid, and examples of the inorganic acid include hydrochloric acid and sulfuric acid. And any one or more of these organic acids or inorganic acids can be used. Of these organic acids or inorganic acids, citric acid is preferably used from the viewpoint of safety to the skin and the like.

  Although it does not specifically limit as an alkaline substance used in the cleaning agent for iron plates of this invention, For example, a sodium orthosilicate, a sodium metasilicate, sodium carbonate, sodium hydrogencarbonate, sodium sesquicarbonate, sodium sulfate etc. are mention | raise | lifted. Of these alkaline substances, sodium orthosilicate is preferably used from the viewpoint of improving the cleaning effect.

  In the iron plate cleaning agent of the present invention, it is necessary to contain a surfactant. Here, since the cleaning agent for iron plate of the present invention is intended to remove oil adhering to the iron plate, a nonionic or anionic surfactant having an excellent degreasing effect should also be used for the surfactant. is required.

  Further, calcium silicate or calcium chloride may be mixed in order to absorb moisture in the air and prevent moisture absorption to the peroxide or carbonate in the components of the iron plate cleaning agent. Furthermore, if necessary, additives such as a chelating agent represented by ethylenediaminetetraacetic acid (EDTA) can be appropriately added.

  Next, the production of the iron plate cleaner of the present invention will be described. First, it is important to prepare a composition in which semiconductor particles, a peroxide and / or carbonate, and an activity promoter are mixed.

  Furthermore, in the preparation of the composition, it is important to mix the semiconductor particles and the peroxide and / or carbonate in advance. As for the mixing method, the materials are not simply mixed batchwise. However, it is important to mix the materials so that they are rubbed together. By such a process and a mixing method, activation of semiconductor particles can be promoted when it becomes a cleaning agent. That is, the iron plate cleaning agent of the present invention is activated by the semiconductor being activated such as electronic excitation, and in addition to the cleaning effect of the conventional alkaline substance and surfactant, the above mixture decomposes the oil and fat components, thereby further cleaning. The effect is improved.

  And after the said process, a composition is produced by adding the activity promoter which is at least 1 type chosen from the group which consists of a sodium compound, an inorganic acid, and an organic acid to the said mixture. Here, the inorganic acid and the organic acid in the activity promoter not only have an activity promoting effect, but also have an effect of maintaining the pH of the cleaning solution in a neutral range when the cleaning agent for iron plate is dissolved in water to prepare the cleaning solution. Will also have.

  And finally, the washing | cleaning agent for iron plates is obtained by mixing an alkaline substance and surfactant into the said composition.

  About the compounding quantity of each component in the cleaning agent for iron plates of this invention, it determines based on the quantity of the composition with which the particle | grains of the semiconductor, the peroxide and / or carbonate, and the activity promoter were mixed.

  That is, with respect to the blending amount of the alkaline substance in the iron plate cleaner of the present invention, the alkaline substance is preferably 2 to 7 parts by weight with respect to 1 part by weight of the composition. Here, when the amount is less than 2 parts by weight, good cleaning performance is not exhibited, and when the amount is more than 7 parts by weight, the cleaning performance may be deteriorated.

  About the compounding quantity of surfactant in the washing | cleaning agent for iron plates of this invention, it is preferable to make it a surfactant become 0.05-1 weight part with respect to 1 weight part of compositions. Here, if the amount is less than 0.05 parts by weight, good cleaning performance is not exhibited, and if it exceeds 1 part by weight, the cleaning performance may be deteriorated.

  Furthermore, the amount of each component in the composition is determined based on the amount of semiconductor particles.

  That is, the amount of peroxide and / or carbonate in the composition is preferably 600 to 850 parts by weight of peroxide and / or carbonate with respect to 1 part by weight of the semiconductor. Here, when the amount is less than 600 parts by weight, good cleaning performance is not exhibited, and when the amount is more than 850 parts by weight, the cleaning performance may be deteriorated.

  The compounding amount of the activity promoter in the composition is preferably 1100 to 1800 parts by weight of the activity promoter with respect to 1 part by weight of the semiconductor. Here, if the amount is less than 1100 parts by weight, good cleaning performance is not exhibited, and if it exceeds 1800 parts by weight, the cleaning performance may be deteriorated.

On the other hand, the method for cleaning an iron plate according to the present invention is characterized in that an oil and fat component on the surface of the iron plate is cleaned using an aqueous solution of the iron plate cleaning agent.
Further, the method for cleaning an iron plate of the present invention is a method for cleaning an iron plate using an aqueous cleaning agent solution containing an alkaline substance, and the semiconductor particles, peroxides and / or Alternatively, a composition obtained by mixing at least a carbonate and an activity promoter in advance is added.
Here, the cleaning method is not particularly limited as long as the oil and fat component on the surface of the iron plate can be cleaned. The method of cleaning by immersing the iron plate in a cleaning tank containing a cleaning agent, and spraying the cleaning agent by spraying the iron plate A method of spraying and cleaning, using a curtain flow coater to flow down the cleaning agent in a curtain shape and passing it through an iron plate, and using these brushes and brush vibrations in combination. Cleaning method.

The iron plate cleaning agent according to the present invention comprises at least a semiconductor particle, a peroxide and / or carbonate, and an activity promoter that is at least one selected from the group consisting of sodium compounds, inorganic acids, and organic acids. Since the composition obtained by mixing, an alkaline substance, and a nonionic or anionic surfactant are contained, the semiconductor in the cleaning component for the iron plate activates electronic excitation and the like in the cleaning solution. In addition to the cleaning effect of conventional alkaline substances and surfactants, they can exhibit good detergency by decomposing dirt substances, and even when the liquid temperature of the cleaning liquid is lower than 60 ° C. You can maintain power.
Therefore, the amount of carbon dioxide discharged from the steelworks can be reduced by reducing the temperature of the cleaning liquid.

  Moreover, since the activity promoter is comprised using at least 1 or more types among a sodium compound, an inorganic acid, or organic acid, the washing | cleaning agent for iron plates which concerns on this invention can improve washing | cleaning performance more.

  Moreover, since the sodium compound is comprised by the sodium silicate and / or sodium phosphate in the cleaning agent for iron plates which concerns on this invention, cleaning performance can be improved more.

  Further, since the composition is obtained by mixing the semiconductor and the peroxide and / or carbonate so as to be mixed, and then mixing the activity promoter, the semiconductor such as electronic excitation is used when the cleaning agent is used. The activity of can be demonstrated.

Specific examples of the present invention will be described below in comparison with comparative examples.
The present invention is not limited to the following examples and comparative examples.

(Production of composition)
First, a composition in which semiconductor particles, a peroxide and / or carbonate, and an activity promoter, which are one of the main raw materials for the iron plate cleaning agent of the present invention, were prepared.
As raw materials, titanium dioxide (manufactured by Teika Co., Ltd., product number: JR-301), sodium percarbonate (manufactured by Kishida Chemical Co., Ltd., product number: 020-72485), sodium carbonate (manufactured by Kishida Chemical Co., Ltd., product number: 010-71245) ), Sodium hydrogen carbonate (manufactured by Kishida Chemical Co., Ltd., product number: 010-71665), citric acid (manufactured by Kishida Chemical Co., Ltd., product number: 000-17285), sodium metasilicate nonahydrate (manufactured by Kishida Chemical Co., Ltd., Product number: 010-72045) and sodium tripolyphosphate (manufactured by Kishida Chemical Co., Ltd., product number: 010-73175) were used.
The composition is prepared by mixing the semiconductor particles and the peroxide and / or carbonate so as to be mixed using a mortar or the like, as described above, in the formulation shown in Table 1, and then other components. Was prepared by mixing using a stirrer or the like.

(Production of detergent for iron plate)
Next, an iron plate cleaning agent was prepared.
As the raw material, the above composition, sodium orthosilicate (manufactured by Kishida Chemical Co., Ltd., product number: 020-72315) and a surfactant were used.
As the surfactant, sodium alkylbenzenesulfonate (manufactured by Nippon Synthetic Detergent Co., Ltd., product number: D-40) was used as the anionic surfactant.
Nonionic surfactants include polyoxyethylene nonylphenyl ether (manufactured by Nikka Chemical Co., Ltd., product number: Sunmol N-95SM, HLB: 13.1), polyoxyethylene alkyl ether (manufactured by Kao Corporation, product number: Emulgen 1135S-70, HLB: 17.9), lipophilic glyceryl monostearate (manufactured by NOF Corporation, product number: Monoguri M, HLB: 1) was used.
As a comparative example, a cationic surfactant and an amphoteric surfactant were used as the surfactant. Specifically, dialkyl ammonium chloride (manufactured by Lion Corporation, product number: Argard 2HT-75) is used as the cationic surfactant, and 2-alkyl-N-carboxymethyl-N-hydroxy is used as the amphoteric surfactant. Ethyl imidazolinium betaine (manufactured by Kawaken Fine Chemical Co., Ltd., product number: Softazoline CH) was used.
As a manufacturing method of the cleaning agent for iron plates, it was prepared by mixing the raw materials with the blending shown in Tables 2 to 13 using a stirrer or the like.

(Preparation of cleaning solution)
Finally, cleaning liquids used in Examples and Comparative Examples were prepared.
The cleaning agent was prepared by adjusting the iron plate cleaning agent to 1 kg with water according to the formulation shown in Tables 2 to 13.

(Cleanability evaluation)
Using the cleaning liquid prepared by the above method, the cleaning performance of the oil and fat component adhering to the iron plate was evaluated.
The iron plate for evaluation was an iron plate having a length of 10 cm, a width of 20 cm, and a thickness of 3 mm, and the polyol ester was applied to the iron plate using a nylon aqueous streak brush so that the coating amount was 3.3 g / m2. After that, it was heated from the back side of the coated surface with a gas stove for about 1 minute and baked.
Detergency evaluation was performed according to the following procedure.
First, 1 L of the cleaning liquid was held at 50 ° C. in a 1 liter glass beaker with a stirrer having a thermostat function, and stirred at 500 rpm.
Next, after immersing the iron plate in a cleaning solution for 180 seconds, washing with running tap water for 30 seconds, drying with a dryer, methylcellulose # 4000 (product number: 020-49105, manufactured by Kishida Chemical Co., Ltd.) having a width of 40 mm and a length of 60 mm Cellulose was included in a nylon water-based streak, and from a height of about 10 cm above the iron plate, the hand holding the brush was struck with the other hand, and the cellulose was evenly sprinkled on the iron plate. Then, the sprinkled surface was turned upside down, and the oil and unfixed methylcellulose remaining on the iron plate were shaken off.
Finally, the surface of the iron plate was divided into 100 grids of 1 cm × 2 cm square, and the number of grids on which methylcellulose powder was not fixed was counted and converted to 100 minutes (cleaning rate) for evaluation. .
In other words, if unwashed oil remains on the iron plate, methyl cellulose is fixed by the oil, so if there is a large number of grids in which methylcellulose powder is not fixed, the detergency is strong, and vice versa. Was determined to have poor cleaning power.
The cleaning rate in this cleaning performance test is not only a chemical cleaning effect by the cleaning liquid but also a cleaning effect by the brush in the actual production line. It was judged that it showed.

(Experimental result)
Table 2 shows the results of performing a cleaning test on the composition 1 prepared in Table 1 and a cleaning solution including three components of sodium orthosilicate and an anionic surfactant.
As shown in Examples 1 to 9 in Table 2, when an anionic surfactant was used, the cleaning rate was 35 to 80%.

Table 3 shows the results of performing a cleaning test on the cleaning liquid comprising the composition 1 prepared in Table 1 and three components of sodium orthosilicate and a nonionic surfactant.
As shown in Examples 10 to 20 in Table 3, when a nonionic surfactant was used, a cleaning rate of 30 to 75% was shown.
Further, even nonionic surfactants showed a cleaning rate of 35 to 75% when polyoxyethylene nonylphenyl ether was used. On the other hand, when polyoxyethylene alkyl ether or lipophilic glyceryl monostearate was used, the cleaning rate was 30%. Therefore, when using a nonionic surfactant, It has been found that it is better to use ethylene nonylphenyl ether.

Table 4 shows the results of a cleaning test performed on cleaning solutions prepared using inappropriate raw materials and blends as comparative examples.
As shown in Table 4, the cleaning rate of the cleaning solution (Comparative Example 1) prepared only with sodium orthosilicate was 0%, and the cleaning solution (Comparative Examples 2 to 5) prepared with two components of sodium orthosilicate and surfactant was used. The rate was 0 to 20%, and the cleaning rate of the cleaning solutions (Comparative Examples 6 to 8) prepared with two components of sodium orthosilicate and the composition was 5 to 15%.
Furthermore, as can be seen from the results of Comparative Examples 9 to 14, a cleaning solution (Comparative Examples 9 to 11) using a cationic surfactant as a surfactant, or an amphoteric surfactant even when three components are contained. The cleaning rate of the cleaning liquid used (Comparative Examples 12 to 14) was 10%.

In Tables 5-7, about the compositions 2-7 created in Table 1, the washing | cleaning liquid provided with three components, sodium orthosilicate, and anionic surfactant, three components of sodium orthosilicate, and nonionic surfactant are included. The results of a cleaning test on the cleaning liquid provided are shown.
As shown in Examples 21 to 50 in Tables 5 to 7, all the cleaning liquids showed a cleaning rate of 30% or more. On the other hand, as shown in Comparative Examples 15 to 20, in the cleaning liquid using the amphoteric surfactant as the surfactant, the cleaning rate was 0% even when the three components were contained.

  From the above results, the cleaning agent for iron plate according to the present invention can exhibit the cleaning power for the first time when the composition, the alkaline substance, and the three components of the nonionic or anionic surfactant are contained. all right.

(Evaluation of low-temperature detergency)
Tables 11 to 13 show cleaning compositions comprising each of the compositions of Table 1 of the present invention, sodium orthosilicate and anionic or nonionic surfactant, and conventional sodium orthosilicate and nonionic surfactant. About the washing | cleaning liquid provided with two components, the temperature of the washing | cleaning liquid was changed and the result of having performed the detergency evaluation of the fat component adhering to the iron plate was shown.

  First, as shown in Table 11, when the temperature of the cleaning liquid is 60 ° C. which is the conventional cleaning temperature, the cleaning liquid of the present invention shows a cleaning rate of 60 to 85% as shown in Examples 51 to 57, As shown in Comparative Example 16, the conventional cleaning liquid also showed a cleaning rate of 30%, which is an acceptable level.

  Next, as shown in Table 12, when the temperature of the cleaning liquid was lowered to 50 ° C., the cleaning liquid of the present invention showed a cleaning rate of 50 to 70% as shown in Examples 6 and 58 to 63. However, as shown in Comparative Example 2, the cleaning rate of the conventional cleaning liquid was significantly reduced to 10%.

  Furthermore, as shown in Table 13, when the temperature of the cleaning liquid was lowered to 40 ° C., the cleaning liquid of the present invention showed a cleaning rate of 30 to 40% as shown in Examples 64-70. As shown in Example 22, the conventional cleaning liquid has a cleaning rate of 0% and does not exhibit cleaning performance.

  From the above results, it was found that the cleaning agent of the present invention exhibits a cleaning effect equivalent to or higher than that of the conventional cleaning agent even when the temperature of the cleaning liquid is lowered from 60 ° C. to 40 ° C. In particular, the cleaning liquid using the composition 1 shows a cleaning rate of 40% (Example 64) even when the cleaning liquid temperature is 40 ° C., and the cleaning rate of the conventional cleaning liquid at 60 ° C. is 30% (comparison). Since the cleaning power exceeding Example 21) was shown, it was found that the iron plate cleaning agent of the present invention has a high cleaning ability even when the temperature of the cleaning solution is lowered.

  The iron plate cleaning agent of the present invention can be used in a cleaning process for cold-rolled steel sheets.

Claims (7)

(A)
(A) semiconductor particles, (b) a peroxide and / or carbonate, and (c) an activity promoter that is at least one selected from the group consisting of sodium compounds, inorganic acids, and organic acids. A composition obtained by mixing;
(B) an alkaline substance;
(C) A cleaning agent for an iron plate, which contains a nonionic or anionic surfactant. The iron plate cleaning agent according to claim 1, wherein the sodium compound is sodium silicate and / or sodium phosphate. The iron plate cleaning agent according to claim 1 or 2, wherein the alkaline substance is sodium silicate. The cleaning agent for an iron plate according to any one of claims 1 to 3, wherein the semiconductor is at least one oxide selected from the group consisting of titanium, vanadium, and iron.   The said composition is obtained by mixing the said activity promoter after mixing the particle | grains of the said semiconductor and the said peroxide and / or the said carbonate so that it may grind | pulverize. The cleaning agent for iron plates as described in any one of these. The cleaning method of the iron plate which wash | cleans the iron plate to which the fat and oil component adhered using the cleaning agent aqueous solution for iron plates as described in any one of Claims 1 thru | or 5. In the iron plate cleaning method of cleaning an iron plate to which an oil and fat component is adhered using a cleaning agent aqueous solution containing an alkaline substance, the semiconductor particles, the peroxide and / or the carbonate in the cleaning agent aqueous solution, A method for cleaning an iron plate, comprising adding a composition obtained by mixing at least the activity promoter in advance.