CN103601811A - Method for causticizing corn starch - Google Patents

Abstract

The invention provides a causticizing method of cornstarch, which is characterized in that the temperature of cornstarch feed water is 40-50°C, stirring while feeding, and after the feeding is completed, it is fully stirred evenly to form a suspension, and then the weight and Sodium hydroxide solution with a volume percentage of 20%, add sodium hydroxide solid mass to corn starch with a mass ratio of 4:100, then raise the temperature to 65-75°C, causticize for one hour, add water to constant volume, and obtain a corn starch solution. Keep warm. By adopting the cornstarch causticizing method of the present invention, the prepared cornstarch solution has uniform and stable properties, is easy to preserve, and is not easy to deteriorate. Used as an iron mineral inhibitor, there will be no "clustering" phenomenon during the preparation process, and the starch utilization rate is high. Reduce the consumption of beneficiation agents by more than 5%, and reduce the energy consumption due to the reduction of causticizing temperature.

Description

Causticizing method of corn starch

technical field

The invention relates to a causticizing method of corn starch.

Background technique

Flotation is an important method of mineral separation. Generally, it is necessary to grind the minerals and add mineral dressing agents for separation. In the reverse flotation process of hematite, corn starch is generally used as an inhibitor of iron minerals.

Starch is an important depressant in reverse flotation of non-polar minerals and hematite. It can play an inhibitory role due to the existence of polar groups such as hydroxyl and carboxyl on the deformed starch molecule. Therefore, starch can associate with water molecules through hydrogen bonds, making the mineral particles affected by it become hydrophilic. The causticization of corn starch is actually a modification process. Causticization can lead to a large degree of swelling and hydration of starch aggregates, which makes the oxygen bridges between the starch molecular rings break and the degree of degradation increases. At the same time, the amylopectin is large The probability of oxidative degradation of molecules increases, and the swelling of starch aggregates partially destroys the association of hydroxyl groups in starch molecules, increasing the probability of hydroxyl groups being oxidized, which is conducive to improving the force between starch molecules and generating relatively more carboxyl groups. The inhibitory effect on iron minerals will be significantly improved.

At present, the preparation method of corn starch in the mineral processing industry is to first put the starch to be prepared into a mixing tank with an appropriate amount of water and stir evenly, then raise the temperature of the mixing tank to 90°C, and add an appropriate amount of 20% sodium hydroxide solution to the mixing tank. Then causticize at 90°C for one hour, add water to make up volume, and set aside. From the preparation and feeding to the causticization process, under the condition of 90°C, the phenomenon of "clustering" often occurs, that is, the gelatinized starch on the surface contains raw starch inside, and the "clustering" is difficult to fully break. In this way, raw starch still remains in the feed liquid after gelatinization, which cannot be used, which not only reduces the utilization rate of starch, but more importantly, it will have a negative impact on the beneficiation index. Therefore, in the mineral processing industry, when corn starch is used as an inhibitor of iron minerals, the causticizing effect of corn starch is particularly important.

Contents of the invention

The purpose of this invention is to provide a kind of causticizing method of cornstarch.

According to the causticizing method of cornstarch according to the present invention, it is characterized in that the temperature of cornstarch cutting water is 40-50°C, stirring while feeding, after the feeding is completed, fully stir evenly, and after forming a suspension, add the weight and Sodium hydroxide solution with a volume percentage of 20%, add sodium hydroxide solid mass to corn starch with a mass ratio of 4:100, then raise the temperature to 65-75°C, causticize for one hour, add water to constant volume, and obtain a corn starch solution. Keep warm.

The method for causticizing cornstarch according to the present invention is characterized in that, in the medicament preparation tank, add water 8 to 10 times the weight of cornstarch, and heat it so that the water temperature is 40-50°C, then add cornstarch , stirring while feeding, the feeding is completed, fully stirred evenly, after forming a suspension, then add a sodium hydroxide solution with a concentration of 20% by weight, and add a solid mass of sodium hydroxide to a mass ratio of cornstarch of 4:100, and then , heat up to 65-75°C, causticize for one hour, add water to constant volume, prepare a cornstarch liquid with a concentration of 1.5-5% by weight, and keep it warm for later use.

In the causticizing method of cornstarch of the present invention, during the causticizing process of cornstarch, since the gelatinization temperature of cornstarch is relatively low, the temperature of the feed water should not be too high, generally not exceeding 50°C. Excessively high feed water temperature will cause corn starch to enter gelatinization without sufficient pre-gelatinization after feed, which will cause changes in the starch crystallization area and become aged starch. After a lot of experimental research, it has been proved that the gelatinization temperature of corn starch is 65-75°C. Due to the fine particle size of cornstarch, the phenomenon of "clustering" can be formed at a higher water temperature, that is, the gelatinized starch on the surface contains raw starch inside, and the "clustering" is difficult to fully break. In this way, raw starch still remains in the feed liquid after causticizing and cannot be used, which not only reduces the utilization rate of starch, but more importantly, it will have a negative impact on the beneficiation index.

By adopting the cornstarch causticizing method of the present invention, the prepared cornstarch solution has uniform and stable properties, is easy to preserve, and is not easy to deteriorate. Used as an iron mineral inhibitor, there will be no "clustering" phenomenon during the preparation process, and the starch utilization rate is high. Reduce the consumption of beneficiation agents by more than 5%, and reduce the energy consumption due to the reduction of causticizing temperature.

Detailed ways

Example:

The causticizing method of corn starch: add water 8 to 10 times the mass of corn starch in the medicament preparation tank, and heat it so that the water temperature is 40 to 50°C, add corn starch, stir while adding, until the addition is complete, fully Stir evenly to form a suspension, then add a sodium hydroxide solution with a concentration of 20% by weight, and add a solid mass of sodium hydroxide to corn starch with a mass ratio of 4:100, and then heat up to 65-75°C and causticize for one hour, add water to make it volume, and prepare cornstarch liquid with a concentration of 1.5-5% by weight, and keep it warm for later use.

The original method is under the condition of 90°C from the process of preparation and feeding to causticization, which reduces the utilization rate of starch, and more importantly, it will have a bad influence on the beneficiation index. The test data obtained by using different configuration methods of corn starch and the data obtained by the flotation test of the same batch of hematite raw ore samples. The comparative data of embodiment method and former method are as follows:

For example: Concentration of cornstarch Utilization rate of cornstarch Chemical consumption Floating grade Floating tail grade

Example 1 1.5% 99% 600g/t 68.12% 11.28%

Original method 1 1.5% 98% 650g/t 68.06% 11.55%

Example 2 2.5% 99% 710g/t 67.88% 10.51%

Original method 2 2.5% 98% 755g/t 67.86% 10.78%

Example 3 4% 99% 680g/t 67.28% 10.41%

Original method 3 4% 98% 730g/t 67.26% 10.68%

Example 4 6% 99% 685g/t 67.27% 10.50%

Original method 4 6% 98% 738g/t 67.23% 10.55%

Example 5 7.5% 99% 630g/t 67.68% 10.75%

Original method 5 7.5% 98% 680g/t 67.65% 10.78%

Example 6 9% 99% 685g/t 67.60% 10.48%

Original method 6 9% 98% 738g/t 67.58% 10.55%

Example 7 10% 99% 660g/t 67.52% 10.88%

The original method 7 10% 98% 670g/t 67.48% 10.92%.

Claims (2)

1. a causticization method for W-Gum, is characterized in that, W-Gum blanking water temp is at 40～50 ℃, while feeding in raw material, stir, fed in raw material, stirred, formed after suspension, adding sodium hydrate solid quality and W-Gum mass ratio is 4-5:100, afterwards, be warming up to 65～75 ℃, causticization one hour, add water constant volume, be mixed with weight percent and be 1.5～10% W-Gum liquid.

2. the causticization method of W-Gum according to claim 1, it is characterized in that, in medicament preparation bucket, add the water of 8～10 times of W-Gum quality, and heat, make water temp at 40～50 ℃, add W-Gum, while feeding in raw material, stir, fed in raw material, stir, form after suspension, adding sodium hydrate solid quality and W-Gum mass ratio is 4:100, afterwards, is warming up to 65～75 ℃, causticization one hour, add water constant volume, be mixed with weight and volume percent and be 1.5～5% W-Gum liquid, be incubated standby.