Liquid ammonia is mainly used for the production of nitric acid, urea, and other chemical fertilizers, and can also be used as a raw material for pharmaceuticals and pesticides.
1. In the national defense industry, it is used to manufacture propellants for rockets and missiles.
2. Used as an ammonification raw material for organic chemical products and also as a refrigerant.
The lone electron pairs in NH3 molecules tend to form coordination bonds with other molecules or ions, generating various forms of ammonia complexes. Complexes such as [Ag (NH3) 2]+, [Cu (NH3) 4] 2+, BF3 • NH3, etc. are all coordinated with NH3.
3. Liquid ammonia is heated to 800-850 ℃, and under the action of nickel based catalysts, ammonia is decomposed to obtain a hydrogen nitrogen mixture gas containing 75% H2 and 25% N2. The gas obtained by this method is a good protective gas
4. It can be widely applied in the semiconductor industry, metallurgical industry, as well as other industries and scientific research that require protective atmospheres.
5. Used in various chemical auxiliary materials, smelting and other industries.
Notes:
Ammonia has a corrosive and irritating effect on the skin tissue in contact, which can absorb water from the skin tissue, denature tissue proteins, saponify tissue fat, and destroy cell membrane structure. Ammonia has extremely high solubility, so it mainly has irritating and corrosive effects on the upper respiratory tract of animals or humans. It is often adsorbed on the skin, mucous membranes, and conjunctiva, resulting in irritation and inflammation. It can paralyze respiratory cilia and damage mucosal epithelial tissue, making it easier for pathogenic microorganisms to invade and weakening the body's resistance to diseases. Ammonia is usually inhaled into the human body in the form of a gas. After being inhaled into the lungs, ammonia easily enters the bloodstream through the alveoli, binds with hemoglobin, and disrupts oxygen transport function. A small amount of ammonia entering the alveoli is neutralized by carbon dioxide, while the rest is absorbed into the bloodstream. A small amount of ammonia can be excreted from the body through sweat, urine, or respiration. In the short term, inhaling a large amount of ammonia can cause tearing, sore throat, hoarseness, cough, bloody sputum, chest tightness, difficulty breathing, and may be accompanied by dizziness, headache, nausea, vomiting, fatigue, etc. In severe cases, pulmonary edema, adult respiratory distress syndrome, and respiratory irritation symptoms may occur. If too much ammonia is inhaled, causing a high concentration of ammonia in the blood, it can cause cardiac arrest and respiratory arrest through the reflex effect of the trigeminal nerve endings, endangering life. Long term exposure to ammonia may cause symptoms such as skin pigmentation or finger ulcers in some people. The ammonia gas in indoor air mainly comes from concrete additives used in construction. Additives contain a large amount of ammonia internal substances, which are reduced to ammonia gas and released in the wall due to changes in environmental factors such as temperature and humidity.
Emergency response:
The physiological effects of ammonia on the human body. Ammonia has a strong irritating odor and is highly toxic to the human body. Chronic ammonia poisoning can cause respiratory diseases such as chronic bronchitis and emphysema, while acute ammonia poisoning is reflected in persistent coughing and suffocation.
(1) Minor leakage.
Evacuate all personnel within the area. Prevent inhalation of vapors and contact with liquids or gases. Personnel handling should use respirators. Prohibit entering confined spaces where ammonia may accumulate and strengthen ventilation. Leakage can only be blocked while ensuring safety. The leaking container should be transferred to a safe area and the valve should only be opened for pressure relief when safety is ensured. Inert absorbent materials such as sand and vermiculite can be used to collect and adsorb leaked materials. The collected leakage should be placed in a sealed container with corresponding labels for disposal.
(2) Large amount of leakage.
Evacuate all unprotected personnel in the venue and transfer them upwind. The leakage disposal personnel shall wear fully enclosed heavy chemical protective clothing and air respirators, and dilute the leakage area with spray water flow after taking personal protective measures. By diluting with a water gun, the ammonia gas on site gradually dissipates, and a spark free tool is used to seal the leakage point.
Report to the local government, "119", local environmental protection departments, public security and traffic police departments, and the content of the report should include the accident unit; The time, location, chemical name, leakage amount, and degree of danger of the accident; Is there any casualties and the name and phone number of the person reporting the incident.
Prohibit contact or crossing of leaked liquid ammonia to prevent leakage from entering sewers and drainage channels.Enhance ventilation. Smoking and open flames are prohibited in the premises. While ensuring safety, it is necessary to plug or flip the leaking container to prevent liquid ammonia from leaking out. Spray water to restrain steam or change the flow direction of steam cloud, but it is forbidden to directly impact the leaked liquid ammonia or leakage source with water. Prevent leakage from entering water bodies, sewers, basements, or enclosed spaces. Prohibit entering confined spaces where ammonia may accumulate. After cleaning, all protective clothing and equipment should be washed away before storage and reuse.
