[Chemical Knowledge]：Properties, uses, upstream and downstream raw materials, storage methods of isobutylene, applications of isobutylene

Isobutene Properties

Isobutylene (isobutene) is an important organic compound with the molecular formula C4H8. It is an unsaturated hydrocarbon and belongs to olefins. Isobutene is a colorless gas at room temperature and has a slight aromatic odor. It has a melting point of -140°C, a boiling point of -6.9°C and a density of 0.589g/cm³. The chemical properties of isobutylene are more active, can react with halogen, acid, oxygen and so on. Its unsaturated double bond allows isobutene to carry out addition reactions and polymerization reactions, which is also the basis for its wide application in chemical production.

Isobutene Uses

As an important chemical raw material, isobutylene has a wide range of applications. It is the key raw material for the production of butyl rubber (butyl rubber). Butyl rubber is widely used in the manufacture of tire inner tubes and pipe seals due to its good air tightness and anti-aging properties. Isobutylene is used to produce methyl tertiary butyl ether (MTBE), a high-octane fuel additive that improves the antiknock properties of gasoline. Isobutene is also an important intermediate for the production of methyl ethyl ketone (MEK), isobutyl acetate, isobutyl benzene, allyl acetate and other chemical products. In the field of medicine, isobutylene derivatives are used in the synthesis of vitamin E, A and other drugs.

Isobutene Upstream Feedstock

The main upstream raw materials of isobutylene include ethylene, propylene, butane, etc. Typically, isobutene is produced by catalytic cracking of butenes or dehydrogenation of isobutane. In petrochemical processes, isobutene can be extracted as a by-product of ethylene and propylene cracking. Isobutane dehydrogenation is one of the important ways to produce isobutene. Isobutene with high purity can be obtained by dehydrogenation of isobutane under high temperature conditions with a catalyst such as platinum, chromium or molybdenum.

Isobutene downstream products

There are many kinds of downstream products of isobutylene, covering rubber, fuel, solvent, medicine, fragrance and other fields. The production of butyl rubber is one of its largest application markets. Butyl rubber has excellent air tightness and chemical resistance and is widely used in automobile tires, seals, medical supplies, etc. As a fuel additive, MTBE can significantly improve the octane number and combustion efficiency of gasoline, and is another important downstream product of isobutylene. In addition, isobutylene can also be used to produce a variety of chemical intermediates and solvents, such as methyl ethyl ketone, isobutyl acetate, etc., these intermediates in coatings, plastics, adhesives and other industries have important applications.

Isobutylene Production Process

The production process of isobutene mainly includes catalytic cracking and dehydrogenation. The catalytic cracking process generally uses a petroleum fraction such as butene to undergo a cracking reaction under a specific catalyst (such as a phosphoric acid catalyst or a molecular sieve catalyst) and high temperature conditions to produce isobutene. Dehydrogenation law is based on isobutane as raw material, high temperature and specific catalyst (such as platinum, chromium, molybdenum catalyst) under the action of dehydrogenation reaction to generate isobutene. These two methods have their own advantages and disadvantages, catalytic cracking method can effectively use petroleum by-products, but the process is complex, dehydrogenation process is simple, easy to control, but the raw material purity requirements are higher.

Isobutylene storage methods

Because isobutylene is a gas at normal temperature and pressure, and has certain flammability and chemical activity, its storage and transportation need special attention. Typically, isobutylene is stored as a liquefied gas in high-pressure or low-temperature tanks. Liquefied storage can significantly reduce its volume and facilitate transportation and use. During storage, it is necessary to ensure the tightness of the storage tank to prevent leakage. Fire prevention and explosion-proof facilities shall be set in the storage area, which shall be far away from fire source and high temperature environment. Regularly check the safety valve, pressure gauge and other equipment of the storage tank to ensure that it operates under safe working conditions.

Isobutylene Safety

Isobutene is a flammable gas that is a risk of combustion and explosion when exposed to open flames, high temperatures or oxidants. Therefore, in the process of production, storage and transportation, it is necessary to strictly abide by the safety operation procedures to avoid static electricity accumulation and fire source contact. Isobutylene has a certain stimulating effect on the human body, and inhalation of high concentrations of isobutylene gas can cause dizziness, headache, nausea and other symptoms. Therefore, wear suitable protective equipment such as protective gloves, protective glasses and respiratory protection when exposed to isobutylene. The workplace should be well ventilated to avoid the accumulation of isobutylene gas.

Environmental impact

The production and use of isobutene has a certain impact on the environment. Isobutene gas leakage can cause air pollution, and long-term exposure to high concentrations of isobutene may cause harm to animal and plant health. Isobutene participates in photochemical reactions in the atmosphere to generate ozone and secondary organic aerosols (SOA), which have a negative impact on atmospheric environmental quality. Therefore, in the production and use of isobutylene, effective environmental protection measures should be taken to reduce emissions and prevent environmental pollution.

Market Prospects

With the advancement of global industrialization and the increase in demand for chemical products, the market demand for isobutylene has shown a steady growth trend. Especially in the automotive industry, construction industry and electronics industry, the increasing demand for high-performance rubber, fuel additives and solvents is driving the expansion of the isobutylene market. With the increasingly stringent environmental regulations, the demand for green and environmentally friendly fuel additives (such as MTBE) is also increasing, which brings new opportunities to the isobutylene market. Market competition is also intensifying, enterprises need to continuously optimize the production process, improve product quality and production efficiency, in order to maintain a competitive advantage.

Conclusion

As an important organic chemical raw material, isobutylene has a wide range of applications and important status in the chemical industry. Its active chemical properties enable it to participate in a variety of chemical reactions and produce a variety of high value-added chemical products. With the progress of technology and the growth of market demand, the application prospect of isobutylene is broad. Its production, storage and use require strict control of safety and environmental protection measures to ensure sustainable development. Through continuous technological innovation and process optimization, the isobutylene industry is expected to usher in a more brilliant development prospects.