I. Introduction
Sodium dihydrogen phosphate dihydrate is an inorganic compound with the appearance of a white crystalline powder, soluble in water. Its chemical formula is NaH2PO4·2H2O, indicating that each molecule contains two molecules of crystalline water, usually colorless to white crystals or crystalline powder, easily soluble in water, almost insoluble in ethanol. Continued heating after loss of water of crystallization at 100°C produces acidic sodium pyrophosphate.
Molecular weight 156.0075
Cas No. 13472-35-0
Related article: Breif introduction to Sodium dihydrogen phosphate dihydrate
II. Uses
Disodium hydrogen phosphate dihydrate can be used to make citric acid, water softener, fabric weight gainer, fire retardant, and used in glazing agent, welding agent, medicine, pigment, and other phosphates. It can be used as industrial water quality treatment agent, printing and dyeing detergent, quality improvement agent, neutralizer, culture agent, biochemical treatment agent, and food quality improvement agent.
a. Water treatment
- In high-pressure boiler systems, sodium dihydrogen phosphate dihydrate is commonly used to maintain proper alkalinity in the boiler while controlling the pH of the water and preventing the production of excessive OH- ions. For optimum water quality control, disodium dihydrogen phosphate is often used in combination with disodium hydrogen phosphate or trisodium phosphate, and appropriate amounts of dispersants are added to minimize deposit formation.
- Sodium dihydrogen phosphate can chelate with calcium and magnesium ions in water to form stable water-soluble complexes, thus reducing water hardness and preventing scale deposition on boilers and pipelines. This reaction not only prevents scale generation, but also extends the service life of the equipment and improves thermal efficiency
b. Weighting agent for tanning and fabrics
In the leather processing and textile industries, disodium hydrogen phosphate dihydrate can be used as a weighting agent to increase the weight and density of materials.
c. Flame retardant for wood and paper
It can also be used in the flame retardant treatment of wood and paper to improve the fire resistance of the material.
d. Mordant for dyeing
In the textile dyeing process, disodium hydrogen phosphate dihydrate can be used as a mordant to help fix the dye.
e. Stabilizer for hydrogen peroxide bleaching
In the process of hydrogen peroxide bleaching, disodium hydrogen phosphate dihydrate can be used as a stabilizer to ensure the bleaching effect and product quality.
f. Food quality improver
Sodium dihydrogen phosphate dihydrate is used as a quality improver in the food industry to increase the complex metal ions, pH and ionic strength of foodstuffs, thus improving the adhesion and water retention of foodstuffs. In addition, it is also used in the fermentation industry as a buffer and baking powder raw materials.
g. Chemical synthesis
Sodium dihydrogen phosphate is the raw material for the manufacture of sodium hexametaphosphate and sodium pyrophosphate.
h. Other applications
Sodium dihydrogen phosphate dihydrate is also used in the preparation of phosphate buffers and SCCP solutions, and as a termination buffer.
III. Difference between sodium dihydrogen phosphate and sodium dihydrogen phosphate in uses
Because sodium dihydrogen phosphate dihydrate can be converted to sodium dihydrogen phosphate, sodium dihydrogen phosphate dihydrate is often used as a precursor to sodium dihydrogen phosphate. However, there are some differences in their applications.
a. In the food industry
Sodium dihydrogen phosphate dihydrate is used as a bulking agent and buffering agent. In contrast, sodium dihydrogen phosphate is used as a food flavoring agent, leavening agent, and nutritional fortifier, among others.
b. In the biological and pharmaceutical fields
Sodium dihydrogen phosphate dihydrate can be used as a regulator and enhancer in cell culture and storage to promote cell growth.In the pharmaceutical industry, sodium dihydrogen phosphate is used as an antacid and a drug to regulate the acid-base balance of body fluids.
IV. Conclusion
Sodium dihydrogen phosphate dihydrate is an inorganic compound that is used in water treatment, leather, food, chemical and pharmaceutical industries. It can be converted into sodium dihydrogen phosphate and is often used as a precursor to sodium dihydrogen phosphate in practical applications. However, although they are similar, in practical application, each has its own strengths. For different industries and applications, the appropriate compounds should be selected for use to ensure the effectiveness of the experimental or processing process.
