Chemwin is a styrene manufacturer and trader established in China. We take the production of high-quality styrene as our own responsibility, and achieve the leading position in China's styrene market. Whether as a supplier or as a manufacturer, our customers can obtain stable quality and reliable delivery from us. Chemwin's mission is to provide customers with high-quality styrene products and the best service.
In addition, our service is also excellent. Our professional sales team develops personalized solutions for customers, and timely response and satisfactory pre-sale and after-sales service are synonymous with high-quality service. We also provide a lot of market information and maintain interaction and contact with customers to better understand the market situation and release the latest updates and trends.
If you need to buy styrene, Chemwin is your first choice. We promise fast and high-quality delivery service, and allow customers to customize different sizes and special specifications, and continue to carry out technical innovation and production upgrading to ensure that our quality and service reach the best state. We sincerely welcome customers at home and abroad to contact us by email or telephone, and look forward to working with you to create a great future.

PRODUCT OVERVIEW

Styrene is an organic compound with the chemical formula of C8H8. The electron of vinyl is conjugated with the benzene ring. It is insoluble in water and soluble in most organic solvents such as ethanol and ether. It is an important monomer for synthetic resin, ion exchange resin and synthetic rubber.

ATTRIBUTES

Density: 0.902g/cm3
Melting point: - 30.6 ℃
Boiling point: 145.2 ℃
Flash point: 31.1 ℃
Refractive index: 1.546 (20 ℃)
Saturated vapor pressure: 0.7kPa (20 ℃)
Critical temperature: 369 ℃
Critical pressure: 3.81MPa
Ignition temperature: 490 ℃
Upper explosion limit (V/V): 8.0%
Lower explosive limit (V/V): 1.1%
Appearance: colorless transparent oily liquid
Solubility: insoluble in water, soluble in most organic solvents such as ethanol and ether

CHEMICAL PROPERTY

Styrene is colorless oily liquid with aromatic smell. Freezing point - 30.6 ℃. The boiling point is 145 ℃. Relative density 0.9051. Flash point (open cup) 31 11℃。 The self-ignition point is 490 ℃. The refractive index is 1. 5467. Viscosity (20 ℃) 0.763mPa - s. Slightly soluble in water, soluble in ethanol, ether, methanol, acetone and carbon disulfide. When heated or exposed to sunlight, or in the presence of peroxide, it is easy to polymerize, which releases heat and can cause explosion. Explosion limit 1. 1%~6 1% by volume.

PRECAUTIONS FOR PROTECTION

Engineering control: the production process is closed and ventilation is strengthened.
Respiratory protection: When the concentration in the air exceeds the standard, it is recommended to wear a filtered gas mask (half mask). In case of emergency rescue or evacuation, it is recommended to wear an isolated respirator.
Eye protection: Generally, no special protection is required, and chemical safety glasses can be worn when exposed to high concentration.
Body protection: wear protective clothing against poison penetration.
Hand protection: wear rubber oil-resistant gloves.
Other protection: smoking, eating and drinking are prohibited at the work site. After work, take a shower and change clothes. Maintain good hygiene habits.

APPLICATION AREA

1. The main use of styrene is as monomer of rubber and plastic, used to produce styrene butadiene rubber, polystyrene, foam polystyrene; It is also used to copolymerize with other monomers to produce engineering plastics with different uses.
2. Styrene is used for organic composition and resin composition, and is used for making copper plating brightener, with leveling and brightening effect.
3. Styrene is used as a hard monomer for making styrene acrylic lotion and solvent pressure sensitive adhesive, and also as a crosslinking monomer for unsaturated polyester resin. Used for making polystyrene, foam polystyrene and styrene butadiene rubber; ABS resin is prepared by copolymerization with acrylonitrile and butadiene; SBS and SIS thermoplastic elastomers are prepared by copolymerization and separation with butadiene and isoprene; Lotion adhesive and coating are prepared by copolymerization with vinyl acetate and acrylate.
4. Styrene is used to form styrene-butadiene rubber and polystyrene resin, polyester glass fiber reinforced plastics and coatings, as well as dye intermediate anthraquinone, pesticide emulsifier, medicine, mineral processing agent styrene phosphonic acid, etc.
5. Styrene is used to make polystyrene, form rubber, ion exchange resin, etc.

PRODUCTION METHOD

There are mainly two methods: catalytic dehydrogenation of ethylbenzene and co-oxidation of ethylbenzene.
1、Catalytic dehydrogenation of ethylbenzene
Ethylbenzene dehydrogenates to styrene at 550~600 ℃ under the action of catalyst:
Dehydrogenation of ethylbenzene is a reversible endothermic and molecular increase reaction. Heating and pressure reduction are conducive to the reaction in the direction of styrene generation. The method adopted in industry is to add a large amount of high-temperature water vapor into the feed to reduce the partial pressure of hydrocarbons and provide part of the heat required for the reaction. The molar ratio of water vapor to hydrocarbon (water ratio for short) varies with the type of reactor, ranging from 6 to 14.
① Catalyst
In the early stage, the magnesium catalyst of the California Standard Oil Company of the United States and the zinc catalyst of the German Faben Company were used. After the Second World War, the catalysts developed by Shell Oil Company of the United States with iron oxide as the main component (Fe2O3: K2O: Cr2O3=87:10:3) were widely used, with the conversion rate of about 60% and selectivity of about 87%. In 1978, a new type of iron-based catalyst with a variety of co-catalysts appeared. The selectivity of styrene reached 95%. Most of the co-catalysts added were alkali metals or alkaline earth metals, such as potassium, vanadium, molybdenum, tungsten, cerium, chromium, etc. In the 1980s, industry continued to make efforts to develop catalysts suitable for low water ratio to save energy consumption.
② Reactor
There are two types of ethylbenzene dehydrogenation reactors: isothermal and adiabatic. The isothermal reactor is tubular and has been rarely used. When the adiabatic reactor is used, the heat required for the reaction is brought in by raising the feed temperature (610~660 ℃) and increasing the water ratio (≈ 14). However, too high temperature will cause the thermal cracking of ethylbenzene. Usually, radial reactors are used to reduce the temperature drop and pressure drop of gas passing through the catalyst layer, and superheated steam is introduced in sections to make the axial temperature distribution uniform.
③ Process flow
It includes ethylbenzene dehydrogenation and styrene distillation separation. The conversion rate of ethylbenzene in the reactor is about 35% - 40%. The dehydrogenation solution contains about 55% - 60% ethylbenzene, 35% - 40% styrene and a small amount of benzene, toluene and tar. The finished styrene can be separated by distillation. Because the boiling points of ethylbenzene and styrene are relatively close, more plates are required for separation, and styrene is very easy to polymerize at higher temperatures. In order to reduce the occurrence of polymerization reaction, in addition to adding polymerization inhibitors such as hydroquinone or sulfur, it is also necessary to adopt decompression operation, and use a new type of tower with high tray efficiency and low resistance or a new type of high efficiency packed tower, so that the tower kettle temperature does not exceed 90 ℃.
2、Ethylbenzene co-oxidation method
Styrene is also commercially produced through the POSM process, and styrene and propylene oxide are obtained from ethylbenzene and propylene. In this production line, ethylbenzene is oxidized by oxygen to form a peroxide of ethylbenzene, which is then used to oxidize propylene to obtain 1-phenylethanol and propylene oxide. Finally, styrene can be obtained after dehydration of 1-phenylethanol.
The characteristic of this method is that 0.4t propylene oxide can be produced simultaneously with each ton of styrene. It does not need the high temperature of dehydrogenation method, and can avoid the pollution of propylene oxide produced by chlorohydrin method. However, the reaction is complex, there are many by-products, the process is long, and the unit consumption of ethylbenzene is higher than that of dehydrogenation.

CONTACT INFORMATION

How to buy from us

Chemwin can provide a wide range of bulk hydrocarbons and chemical solvents for industrial customers.
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Before that, please read the following basic information about doing business with us:

1.security

Safety is our top priority. In addition to providing customers with information about the safe and environmentally friendly use of our products, we are also committed to ensuring that the safety risks of employees and contractors are reduced to a reasonable and feasible minimum. Therefore, we require the customer to ensure that the appropriate unloading and storage safety standards are met before our delivery (please refer to the HSSE appendix in the general terms and conditions of sales below). Our HSSE experts can provide guidance on these standards.

2.Delivery method

Customers can order and deliver products from chemwin, or they can receive products from our manufacturing plant. The available modes of transport include truck, rail or multimodal transport (separate conditions apply).
In the case of customer requirements, we can specify the requirements of barges or tankers and apply special safety/review standards and requirements.

3.Minimum order quantity
If you purchase products from our website, the minimum order quantity is 30 tons.

4.payment
The standard payment method is direct deduction within 30 days from the invoice.

5.Delivery documentation

The following documents are provided with each delivery:

• Bill of Lading, CMR Waybill or other relevant transport document
• Certificate of Analysis or Conformity (if required)
• HSSE-related documentation in line with regulations
• Customs documentation in line with regulations (if required)