Hydrogen Gas has a wide range of applications, among which the largest amount is used as an important petrochemical raw material for the production of synthetic ammonia, methanol and hydrogenation in petroleum refining process. Hydrogen is widely used in electronics industry, metallurgy industry, food processing, float glass, fine chemical and organic synthesis, aerospace industry and other fields are also widely used. As an energy source, hydrogen is the fuel for fuel cells used in future power generation and electric vehicles.

 Petrochemical Industry

Hydrogen is one of the basic raw materials of modern oil refining industry and chemical industry, and hydrogen is used in a wide range of forms in the petrochemical industry. The main raw materials of synthetic ammonia production in China are coal to gas, natural gas, naphtha and heavy oil. A 1000t/d scale ammonia plant requires about 336m3 of hydrogen for each 1t of ammonia production. As with ammonia, most of the hydrogen for methanol synthesis is also produced from coal to gas, natural gas, naphtha or heavy oil, and a methanol plant with a daily kiloton scale requires about 560 m3 of hydrogen to produce 1t of methanol. Since methanol is a basic organic chemical feedstock and can be used as an alternative fuel, the amount of hydrogen used for methanol synthesis is likely to continue to grow.

The amount of hydrogen used in petroleum refining industry is second only to synthetic ammonia. In the petroleum refining process, hydrogen is mainly used for naphtha hydrodesulfurization, crude diesel hydrodesulfurization, fuel hydrodesulfurization, improving the performance of aircraft fuel and hydrocracking. In the field of petrochemical, hydrogen is mainly used for C3 distillate hydrogenation = gasoline hydrogenation, C6~C8. Distillate hydrodealkylation and cyclohexane production.

The hydrogenation of catalytic reforming feedstock is to remove sulfide, nitride, lead, arsenic and other impurities in naphtha, which is the earliest process used in petroleum refining industry. Hydrocracking is a catalytic cracking process in the presence of hydrogen, and the main characteristic of the reaction is C-C bond fracture. Selective hydrogenation is mainly used for pyrolysis products at high temperature, with gas phase hydrogenation for ethylene distillate and liquid phase hydrogenation for propylene distillate.

Hydrofining is also the process of removing harmful compounds, in addition to hydrogen sulfide, mercaptan, total sulfur, alkynes, olefins, metals and quasi-metals can be removed in the hydrogenation process. Therefore, in the modern petrochemical processing process, the use of hydrogenation process can improve the quality of petrochemical chemicals, increase the production of the most valuable petrochemical chemicals, reduce the generation of heavy oil residue and tar, reduce the amount of carbon, improve the adaptability of petroleum processing plants, from petroleum processing waste can get a lot of valuable petrochemical products, purify a series of products, Remove harmful impurities. Hydrogen is the most common chemical agent for modern petroleum processing industry products, which can improve the production capacity of large cracking units.

In the field of petrochemical industry, hydrogen and carbon monoxide can also be used to synthesize a variety of organic compounds, such as the synthesis of ethylene glycol, the synthesis of polymethene, the homology reaction of alcohol, and the reaction with unsaturated hydrocarbons to produce aldehydes. In addition, selective hydrogenation can be used to produce alcohols from aldehydes, olefins from alkynes, anilines from nitrobenzene and hydrogenated naphthalene from naphthalene.

Electronic Industry

In the growth of some electronic materials and substrate preparation, oxidation process, epitaxy process and chemical vapor deposition (CVD) technology, hydrogen is used as reaction gas, reduction gas or protection gas. The production of semiconductor integrated circuits requires very high gas purity, such as the allowable concentration of oxygen impurities of 10-12. The "incorporation" of trace impurities will change the surface characteristics of the semiconductor, and even reduce the product yield or cause waste.

In the manufacture of amorphous silicon solar cells, high purity hydrogen is also needed. Amorphous silicon thin film semiconductor is a new material successfully developed in the world in the past ten years, and has shown attractive application prospects in the fields of solar energy conversion and information technology.

The application and development of optical fiber has been used on a scale, quartz glass fiber is the main type of optical fiber, in the fiber prefabrication process, need to use hydrogen and oxygen flame heating, after dozens of deposition, hydrogen purity and cleanliness have certain requirements.

Float Glass Production Process

Gases widely used in the glass industry are hydrogen, acetylene, oxygen and nitrogen. In the production of float glass, in order to prevent the liquid tin in the tin tank from being oxidized, nitrogen and hydrogen mixture is used to protect the tin tank, and the purity of the gas is high, of which the purity of hydrogen is 99.999%.

 Metallurgical Industry

In the gold industry, hydrogen is mainly used as a reduction gas to reduce metal oxides to metals. In addition to the reduction of several metal oxides to produce pure metal, hydrogen is often used as a protective gas in high temperature forging of some metal equipment to prevent the metal from being oxidized.

Food Processing Industry

Many natural edible oils have a large degree of unsaturated, after hydrogenation treatment, the products can be stably stored, and can resist the growth of bacteria, improve the viscosity of oil. The hydrogen used for vegetable oil hydrohydrogenation has high purity requirements and generally needs to be strictly purified before being used. Edible oil hydrogenation products can be processed into margarine and edible protein. Non-edible oil hydrogenation can obtain raw materials for soap production and animal husbandry feed. The process involves introducing hydrogen into the composition of a liquid fat or vegetable oil by saturating a glycerine with a hydrogen unsaturated acid (oleic acid, linoleic acid, etc.).

Space Technology and Gas Applications

There are many advantages of hydrogen as aviation fuel, it can not only meet many requirements of future aviation fuel, the most important is that hydrogen fuel does not pollute the environment.

Using hydrogen as fuel is superior to hydrocarbon fuel in many aspects, foreign countries began to develop the problem of using hydrogen as vehicle fuel in the 1960s, conventional internal combustion engines can be used as fuel with a little modification.

Japan has conducted a feasibility study on a superconducting maglev train fueled by liquid hydrogen. Boeing and the Lewis Research Center in the United States have conducted feasibility studies on liquid hydrogen aircraft. It is foreseeable that hydrogen will replace hydrocarbon as fuel in the near future.

Hydrogen and oxygen can be used for welding or melting of metals and non-metals. Hydrogen in oxygen combustion temperature can be more than 3100K, hydrogen through the arc flame decomposition into atomic hydrogen, atomic hydrogen can be used for the most difficult to melt metal, high carbon steel, corrosion resistant materials, non-ferrous metals and other melting and welding. The advantage of welding with atomic hydrogen is that the hydrogen beam can prevent the welding site from being oxidized, so that the welding site does not produce oxide

As an energy source, hydrogen is the fuel for fuel cells used in future power generation and electric vehicles. Fuel cell is the chemical energy of hydrogen fuel and oxidizer directly converted into electricity, high conversion efficiency, the product is water, no pollution to the environment known as "zero emission", hydrogen is the future of human clean energy.

Other applications

(1) Because hydrogen has a high thermal conductivity, hydrogen is commonly used as a coolant in large generator sets.

(2) In scientific research requiring ultra-low temperatures, hydrogen is commonly used as a refrigerant.

(3) Hydrogen is commonly used as carrier gas in gas chromatographic analysis.

(4) Due to its low density, hydrogen can also be used to fill balloons and airships.

(5) The use of metal hydride hydrogen absorption heat release, dehydrogenation heat absorption properties, can establish a heat pump cycle or heat adsorption compressor.