What is disodium hydrogen phosphate and its use?

What is disodium hydrogen phosphate and its use?

Disodium hydrogen phosphate, with the chemical formula Na₂ HPO-H2O, is an inorganic compound that belongs to the phosphate class. It is a white or colorless crystalline solid, odorless, slightly soluble in water, but its solubility in water increases with increasing temperature. Disodium hydrogen phosphate is widely used in industry, agriculture, medicine and food. This paper will analyze its basic properties, preparation methods and uses in detail.

1. of Disodium Hydrogen Phosphate Basic Properties

Disodium hydrogen phosphate is a neutral salt produced by the reaction of phosphoric acid (H03PO4) and sodium hydroxide (NaOH). Its aqueous solution is weakly alkaline, with a pH value of about 8.0. Disodium hydrogen phosphate has a molar mass of about 141.96g/mol, a melting point of 244°C and a boiling point of 1740°C. Its solubility in water varies greatly with temperature, being about 14.8g/100 mL water at 20°C and 40g/100 mL water at 80°C.

2. disodium hydrogen phosphate preparation method

Disodium hydrogen phosphate is mainly produced by the neutralization reaction of phosphoric acid with sodium hydroxide or sodium carbonate. The specific process is as follows:

1. Neutralization reaction method: the concentrated phosphoric acid is mixed with sodium hydroxide solution, and the reaction conditions are controlled to generate disodium hydrogen phosphate.

   The reaction formula is: H₃PO₄ NaOH → NaH₂PO₄ H₂O NaH₂PO₄ NaOH → Na₂HPO₄ H₂O

2. Crystallization separation method: by evaporating and concentrating the neutralization solution, the disodium hydrogen phosphate is crystallized out, and then filtered and dried to obtain the finished product.

The method is simple in process and low in cost, and is the main way for industrial production of disodium hydrogen phosphate.

3. of disodium hydrogen phosphate main use

Disodium hydrogen phosphate has important applications in many fields because of its unique physical and chemical properties.

1. Food Additives Disodium hydrogen phosphate is often used as a food additive, mainly for food preservation, antioxidant and pH adjustment. For example, adding the right amount of disodium phosphate to pasta, dairy and beverages can extend shelf life and improve flavor. It can also be used as a leavening agent and stabilizer in food processing.

2. medical field Disodium hydrogen phosphate is mainly used in the pharmaceutical industry for the production of antacids and diuretics. For example, when disodium hydrogen phosphate is mixed with sodium bicarbonate, it can be used as an antacid to relieve discomfort caused by excessive stomach acid. It is also used in the preparation of other pharmaceutical intermediates.

3. Industrial Cleaning Disodium hydrogen phosphate is an efficient metal cleaning agent, especially suitable for degreasing and rust removal of steel, aluminum and other metals. Its alkaline properties can effectively decompose grease and oxides, and at the same time has anti-rust function, widely used in machinery manufacturing and automobile maintenance industry.

4. Agricultural Applications Disodium hydrogen phosphate can be used as a plant nutrient for the preparation of compound fertilizers. It can provide phosphorus for plants, promote plant growth and increase yield. Disodium hydrogen phosphate can also be used for water treatment to adjust the pH value of water quality.

4. disodium hydrogen phosphate safety and storage

Although disodium hydrogen phosphate is widely used in many fields, its treatment still needs to pay attention to safety. In case of contact with skin or eyes, rinse immediately with plenty of water. Storage should be placed in a cool, dry, ventilated place, avoid contact with acidic substances.

5. of Disodium Hydrogen Phosphate in the Future

With the progress of science and technology, the application field of disodium hydrogen phosphate will be further expanded. For example, in the field of new energy materials and environmental protection, disodium hydrogen phosphate may be used as a precursor for preparing lithium iron phosphate batteries or as a water treatment agent. Its highly efficient and versatile features will continue to drive its use across multiple industries.

As an important inorganic compound, disodium hydrogen phosphate not only plays a key role in industrial production, but also shows a wide range of applications in food, medicine and agriculture. With the continuous progress of technology, the use of disodium hydrogen phosphate will be more diversified, and its importance will be further enhanced.