Ammonium chloride (NH4Cl) is an importantinorganic compound that has a wide range of industrial and agricultural applications. The following is a detailed introduction to the preparation method and application field of ammonium chloride:
Preparation method of ammonium chloride
1. Hou's soda process: This is a method ofproducing soda ash and ammonium chloride at the same time, invented by the famous Chinese scientist Hou Debang.
2. Compound decomposition method: First,the mother liquor of ammonium chloride was added to the reactor and heated to 105℃, then ammonium sulfate and salt were added, and the complex decomposition reaction was carried out at 117℃ to generate ammonium chloride solution and sodium sulfate crystals. After filtration and separation, sodium sulfate was
removed, and the saturated solution of ammonium chloride was sent to the cooling crystallizer, which was cooled to 32 ~ 35℃ for crystallization and filtration. The crystals were washed with 4 different concentrations of ammonium chloride solution, and Fe < 0.008% and < 0.001% were controlled. After the crystallization was washed until qualified, the crystals were re-adjusted into slurry with ammonium chloride solution, sent to centrifuge for separation and dehydration, and then dried by hot air to obtain industrial ammonium chloride finished products.
3. Gas-liquid phase synthesis method: thehydrogen chloride gas is passed into the bottom of the turbulent absorption tower and contacted with the circulating mother liquor sprayed on the top of the tower, and the ammonium chloride mother liquor generated by saturated hydrogen chloride flows into the reactor, and the neutralization reaction is carried out with the incoming ammonia gas to generate the saturated ammonium chloride solution. Sent to the cooling crystallizer, after cooling to 30 ~ 45℃, the supersaturated ammonium chloride crystal is precipitated. The ammonium chloride solution on the upper part of the mold is sent to the air cooler for cooling and circulation to the mold; The lower crystal slurry was thickened by
thickener and then centrifuged to get ammonium chloride finished product.
Application field of ammonium chloride
1. Agriculture: Ammonium chloride is aphysiological acid fertilizer, suitable for rice, wheat, cotton, hemp, vegetables and other crops. However, because it contains more chlorine, it is
not suitable for application on acidic soil and saline-alkali soil, and it is not suitable for application on chlorine-sensitive crops (such as tobacco, potatoes, citrus, tea trees, etc.).
2. Industrial raw materials: Ammoniumchloride can be used as raw materials for the manufacture of dry batteries and batteries, other ammonium salts, electroplating additives, and metal welding fluxes.
3. Medicine: Ammonium chloride canstimulate the gastric mucosa, reflexively stimulate the respiratory glands, promote the secretion of bronchial glands, make sputum thin, easy to cough up, and present expectorant effect. In addition, ammonium chloride is used to correct metabolic alkalosis.
4. Dyes and printing and dyeing: ammoniumchloride can be used as dyeing AIDS for tinning and galvanizing, tanning leather, candle making, adhesives, chromizing, precision casting, etc.
5. Analytical reagent: ammonium chloride isused as an analytical reagent, such as preparing ammonia-ammonium chloride buffer solution, supporting electrolyte for electrochemical analysis, arc stabilizer for emission spectrum analysis, interference inhibitor for atomic
absorption spectrum analysis, test of synthetic fiber viscosity, etc.
6. Food industry: Ammonium chloride canalso be used in the food industry, such as as yeast nourishment (mainly used in beer brewing), dough conditioner, etc.
In summary, the preparation methods ofammonium chloride are diverse, and its application fields cover many important industries such as agriculture, industry, medicine, etc., showing its
importance and wide application prospects in modern society.