Preparation methods and purification technologies for special gases refer to the process of special treatment and processing of specific gases or gas mixtures in the laboratory or industrial production to achieve the required purity, concentration, pressure and other indicators. These gases are widely used in electronics, metallurgy, medical treatment, scientific research and other fields.
I. Preparation Methods
1. Electrolysis method: It is suitable for the preparation of common gases, such as hydrogen and oxygen. By electrolysis of water or salt solution, the size of current and electrolysis time can be controlled so as to obtain gases of different purity.
2. Chemical reaction method: The desired gas is produced by a chemical reaction. For example, hydrogen peroxide can be decomposed to produce oxygen, nitrates can be heated to produce nitrogen, etc.
3. adsorption method: the desired gas is separated from the gas mixture by using the adsorption effect of adsorbent. Commonly used adsorbents are activated carbon, molecular sieve, etc. 4.
4. distillation method: the different boiling points of gases are utilised to separate the required gases by distillation. Rotary evaporators are usually used for laboratory operations.
II. Purification techniques
1. Coagulation methods: Separate the required gases by lowering the temperature of the gas so that the impurities condense into liquid or solid.
2. washing method: use appropriate liquid or solid absorbent to absorb the impurities in the gas and obtain relatively pure gas.
3. analysis method: using the difference of adsorption or dissolution properties of different substances on the chromatographic column to separate the impurities from the desired gas.
4. Heating method: volatilise or decompose the impurities by heating, so as to obtain relatively pure gases.
In the process of preparing and purifying special gases, it is necessary to choose suitable preparation methods and purification techniques according to the specific types of gases and application needs. At the same time, in order to achieve the purpose of economy, safety and environmental protection, it is also necessary to pay attention to the safe operation and environmental protection requirements.
Post time: Sep-24-2024