Is sodium metaaluminate a strong base? Properties of sodium metaaluminate

Sodium metaaluminate chemical formula Naalo2, white, odorless, tasteless, melting point 1650, a strong alkaline solid, high temperature melting product is white powder, soluble in water, insoluble in ethanol, easy to absorb water and carbon dioxide in the air, easy to precipitate aluminum hydroxide after dissolving in water, aluminum hydroxide dissolved in sodium hydroxide solution also produces sodium metaaluminate solution. It is used as a mordant for textiles, a filler for paper, and a purifying agent for water. It can be prepared by co-melting alumina with solid sodium hydroxide or sodium carbonate.

Sodium metaaluminate encounters weak acid and a small amount of strong acid to form white aluminum hydroxide precipitate, and the phenomenon is that a large number of white precipitates are generated, and the amount of final precipitate remains unchanged. In the case of excessive strong acid formation, the corresponding aluminum salt is formed, and the phenomenon is that there is a white precipitate first, and after a period of time, the mass of the white precipitate gradually decreases and finally disappears. Sodium metaaluminate and alkali do not work.

Because it itself is alkaline due to the hydrolysis of metaaluminate ions, it does not interact with alkaline.

In the textbook of the People's Education Edition, it is written that aluminum hydroxide is dissolved in sodium hydroxide solution to form sodium metaaluminate solution, and in the later chemistry textbook (compulsory one) published by Shandong Science and Technology Press, it is said that Al and NaOH react with water to form sodium Na[Al(OH)4]tetrahydroxyaluminate. In fact, sodium metaaluminate exists in the form of Na[Al(OH)4] and in aqueous solution, which was abbreviated as Naalo2 for convenience.

But its actual composition is still na[al(OH)4].

In the construction process, this product is mixed with water glass for leakage plugging agent in construction; In the paper industry, this product is mixed with aluminum sulfate and is a good filler; This product can be used as a water purification agent additive to improve the effect of water purification, reduce the hardness of water and accelerate the settlement of suspended solids. Cement construction, this product can be used as a cement quick-setting agent, which can promote the rapid setting of cement, and is an ideal additive for underground and rapid construction, and cement requires fast setting; It can be used as a raw material for catalysts and catalytic carriers in petroleum, chemical and other industries. The production of high-grade white paint can be used as a surface treatment agent; In addition, this product is also widely used in the production of textile, printing and dyeing, pharmaceutical, rubber, laundry detergent, steel surface treatment, etc.

Main uses: In civil engineering, this product is mixed with water glass for leak plugging in construction.

In the paper industry, this product is mixed with aluminum sulfate as a good filler.

In terms of water treatment, it can be used as a water purification agent auxiliary.

It can be used as a cement quick-setting agent.

It is also widely used in petrochemical, pharmaceutical, rubber, printing and dyeing, textile, and catalyst production.

The product is used in the production process of titanium dioxide to coat its surface and improve its properties.

It is used as a mordant for textiles, a filler for paper, and a purifying agent for water. It can be prepared by co-melting alumina with solid sodium hydroxide or sodium carbonate.

Manufacture of zeolite, milky glass, and soap.

Sodium metaaluminate is not present in solution, and sodium metaaluminate can be formed by a solid-state high-temperature reaction.

The compound formed by the reaction of a solution of aluminum metal and sodium hydroxide was once thought to be Naalo2, but scientific research has shown that the product is actually Na[Al(OH)4] (sodium tetrahydroxyaluminate), which is a coordination compound.

Sodium metaaluminate is an alkaline substance with the chemical formula Naalo2. Sodium metaaluminate is a white particle, easy to absorb moisture, very soluble in water, insoluble in ethanol, and the aqueous solution is strongly alkaline.

Chinese name: sodium metaaluminate.

Chinese aliases: sodium aluminate; sodium leadate;

Product Name: Sodium Aluminum Synonyms: Sodium Metaaluminate; aluminum sodium oxide sodium aluminum oxide;sodium aluminate;

CAS Number: 11138-49-1

Sodium metaaluminate chemical molecular structure.

Molecular formula: AlnaO2

Molecular weight: Exact mass:

PSA: white particles, easy to absorb moisture, very soluble in water, insoluble in ethanol, aqueous solution is strongly alkaline, melting point: 1650 C.

Preparation. 1.Aluminum elemental reacts with sodium hydroxide to release hydrogen:

2naoh+2al+2h2o=2naalo2+3h2↑2.Alumina and sodium hydroxide reaction:

al2o3+2naoh=2naalo2+h2o<>

Properties: white amorphous crystalline powder, hygroscopic.

Density (g ml, 25):

Melting point (c): 1800.

Refractive index (n20 d): .

Solubility: soluble in water, insoluble in ethanol.

Common chemicals, white, odorless, tasteless, strong alkaline solid. It is widely used in civil engineering, petrochemical industry, water treatment and other aspects.

The same substance.

Sodium aluminate is an important inorganic chemical jujube commodity. It is an efficient raw material for the generation of aluminium hydroxide, which is widely used in industry and science and technology. Pure sodium aluminate (anhydrous) is a white crystal that manifests itself in a variety of molecular forms such as Naalo2, Na2O·Al2O2, or Na2Al2O4

Sodium aluminate is obtained by dissolving aluminum hydroxide in a caustic soda solution. Trivalent aluminium hydroxide (diaspore) can be dissolved in a caustic soda solution containing 20 25 water, at a temperature close to the boiling point. The use of a higher concentration of caustic soda solution produces a semi-solid product, the reaction must be carried out in a steam-heated nickel or steel vessel, while the aluminium hydroxide should be boiled with 50 caustic soda until a pulp-like substance is formed, and the final mixture is poured into a tank to cool, so that a solid substance containing 70 Naalo2 is formed.

After crushing, it is dehydrated in a heated rotary oven and heated directly or indirectly with burning hydrogen, resulting in a final product consisting of 90 parts of Naalo2 and 1 of water, and 1 of free caustic soda.

Sodium metaaluminate naalo2

Sodium metaaluminate] chemical formula Naalo2, is a shorthand for it. In fact, it may be na[al(oh)4] or na3[al(oh)6].The high-temperature melting product is white powder, and the aluminum hydroxide dissolved in the sodium hydroxide solution also forms a partial sodium aluminate solution.

Melting point 1650Soluble in water, insoluble in ethanol. It is very alkaline and can gradually absorb water to form aluminum hydroxide.

It is used as a mordant for textiles, a filler for paper, and a purifying agent for water. It can be prepared by co-melting alumina with solid sodium hydroxide or sodium carbonate. al2o3(s)＋2naoh(s)2naalo2(s)＋h2o(g)

Sodium metaaluminate, white particles, easy to absorb moisture. It is very soluble in water, insoluble in ethanol, and the aqueous solution is strongly alkaline. Melting point 1650

It can react with hydrochloric acid, the reaction is a white precipitate, and then the precipitate disappears, and the reaction equation is as follows: Naalo2+HCl+H2O==Al(OH)3 +Naclal(OH)3+3HCl==AlCl3+3H2O. It is mainly used as: mordant, coarse water softening agent, making zeolite, milky glass and soap.

Sodium metaaluminate is not present in solution, and the compound formed by the reaction of aluminum metal and NaOH solution was once thought to be Naalo2. However, scientific research has proved that the product is actually Na[Al(OH)4]tetrahydroxysodium aluminate, which is a coordination compound. Li Shi wanted to prepare sodium metaaluminate with the formula Naalo2 by adding activated alumina to molten rock disturbed mode sodium hydroxide, and the product was sodium metaaluminate and water.

Summary. Hello, <>

The reason for the high specific gravity but low caustic of sodium aluminate solution is that it contains more solid sodium aluminate, which is denser than most aqueous solutions.

What is the reason for the high specific gravity of sodium aluminate solution but low caustic?

Hello, Zheng Lun <>

The reason why the specific gravity of the sodium aluminate solution is higher but the caustic is lower because it contains more solid sodium aluminate, and the density of sodium aluminate is higher than that of most aqueous solutions.

The causticity of the sodium aluminate solution is low, because the sodium aluminate itself is a weak alkaline substance, and its acid-base properties in water are mainly determined by the relative concentration of aluminum ions and hydroxide ions, while the chemical formula of sodium aluminate socks is NaAl(OH)4, in which the concentration of hydroxide ions is relatively low, so its caustic degree is relatively low.

During the evaporation process of the evaporator, if the AO content is large, will it affect the concentration of caustic soda.

During the evaporation process of the evaporator, if the AO (active rubber contact oxygen in solution) content is higher, it may affect the concentration of caustic soda Liang Natan. This is because caustic decomposes at high temperatures, and solutions with high AO content produce more free radicals during heating, which may accelerate the decomposition of caustic, thus affecting the concentration of caustic.

In addition, the concentration of caustic soda may also be affected by other factors, such as the temperature and pressure of the evaporator, the design and operation of the evaporator. Therefore, in practice, it needs to be adjusted and controlled according to the specific situation to ensure that the concentration of caustic alkali is stable and meets the requirements.

This is today's indicator, steamed mother NK186 184, steamed original can reach 190 before 142 143, the evaporator's rock is basically unchanged, is it related to the content of AO, and the proportion of today's steamed mother is not low.

Pro, the steamer nk186 184 and the steamer can reach 190 before 142 143, and now the indicator of Xiaolu Lutian is the steamer nk186 184, which means that the evaporator uses the nk186 184 solution. Generally speaking, when other conditions of the steamer are basically unchanged, the specific gravity of the steamer is not low, which may be related to the content of AO in the solution.

During the evaporation process, the higher AO content in the solution will increase the viscosity and surface tension of the solution, which will affect the heat transfer and mass transfer in the evaporator, resulting in a decrease in the efficiency of the evaporator. Therefore, it is necessary to pay attention to controlling the content of AO in the solution to ensure the normal operation of the evaporator and the quality of the product.

In addition, other conditions of the evaporator may also affect the evaporation process and the specific gravity of the evaporator, such as temperature, pressure, flow rate, evaporator design and operation, etc. Therefore, in the actual operation of Luboxiao, it is necessary to adjust and control according to the specific situation to ensure the stability of the production process and the consistency of the quality and quantity of the production process. Thank you.

Chemical formula Naalo2, white, odorless, tasteless, melting point 1650, is a strong alkaline solid, high temperature melting product is white powder, soluble in water, insoluble in ethanol, easy to absorb water and carbon dioxide in the air, easy to precipitate aluminum hydroxide after dissolving in water, aluminum hydroxide dissolved in sodium hydroxide solution also produces sodium metaaluminate solution.

2naalo2+co2+3h2o==2al(oh)3↓+na2co3

According to the classification of substances, sodium metaaluminate is not a base, it is salt.

Because it is a strong alkaline and weak salt, its aqueous solution is hydrolyzed and alkaline.

Note: Alkaline alkaline, but alkaline is not necessarily alkaline, like our commonly used sodium carbonate, which is salt, but its aqueous solution is also alkaline.

Reasons why the aqueous solution of sodium metaaluminate is alkaline:

The water of Naalo2 ALO2-+2H2O == (reversible) ==AL(OH)3+OH- (produces hydroxide, alkaline).

That's the right answer