The first artificial preparation of hydrogen (H2) was at the beginning of16th century. The method used at that time was to put the metal into strong acid. In industry, natural gas or water gas is generally used to produce hydrogen instead of electrolyzed water with high energy consumption.
Hydrogen is flammable and explosive, so pure hydrogen is very dangerous. If there is a sharp knocking sound during combustion, it means that hydrogen is impure; It is easy to explode, so we must pay enough attention to it.
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Because hydrogen is a flammable compressed gas, it should be stored in a cool and ventilated warehouse. The temperature in the warehouse should not exceed 30℃. Stay away from fire and heat sources. Avoid direct sunlight. It should be stored separately from oxygen, compressed air, halogen (fluorine gas, chlorine gas, bromine) and oxidant to avoid mixed storage and transportation.
The lighting, ventilation and other facilities in the warehouse should be explosion-proof, and the switch should be located outside the warehouse, equipped with corresponding varieties and quantities of fire-fighting equipment. It is forbidden to use mechanical equipment and tools that are easy to generate sparks. Pay attention to the product name, bottle inspection date and the first use of the advanced warehouse during acceptance. Lightly load and unload when handling, so as to prevent the cylinders and accessories from being damaged.
Although hydrogen is non-toxic and physiologically inert to the human body, if the hydrogen content in the air increases, it will cause hypoxia and suffocation. Like all cryogenic liquids, direct contact with liquid hydrogen can cause frostbite. Liquid hydrogen overflow and sudden large-scale evaporation will also cause environmental hypoxia, and may form an explosive mixture with air, causing combustion and explosion accidents.
When it is mixed with air, it can form an explosive mixture, and it will explode in case of heat or open flame. Gas is lighter than air. When used and stored indoors, the leaked gas rises and stays on the roof, which is not easy to be discharged. When it meets Mars, it will cause an explosion. Hydrogen reacts violently with halogens such as fluorine, chlorine and bromine.
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