Tetrahydrofuran

Tetrahydrofuran

1. Product introduction

Tetrahydrofuran (Tetrahydrofuran) is a heterocyclic organic compound, the molecular formula is C4H8O. Belongs to the ether class, is the aromatic compound furan complete hydrogenation product, is a colorless, can be miscible with water, at room temperature and pressure with small viscosity of organic liquid. The chemical formula for this ring ether may be written (CH2)4O. Because of its long liquid range, it is a commonly used medium polar aprotic solvent. Its main use is as a precursor of high polymer. Although THF has a similar smell and chemical properties to ether, the anesthetic effect is poor.

2. Product Parameters (Specifications)

3. Product features and uses

1, used as a solvent, organic synthesis of raw materials. [1]

2, used as chromatographic analysis reagent, organic solvent and nylon 66 intermediate. Tetrahydrofuran heterocyclic rings, also known as a oxygen oxygen pentane, tetramethylene oxide, is a synthetic pesticides benzene Ding Xi intermediates, on the other hand, can be directly used in synthetic fiber, synthetic resin, synthetic rubber, is also many polymer materials, precision tape and electroplating industrial solvents, are also used in adiponitrile, adipic acid, hexamethylenediamine, succinic acid, butyl glycol, gamma butyrolactone and so on, in the pharmaceutical industry, It can be used in the production of cep, progesterone, rifamycin and pharmaceutical solvent. [1]

3, tetrahydrofuran is a kind of important organic synthetic raw material and solvent of excellent performance, particularly applicable to dissolve PVC, polyethylene vinylidene chloride and butyl aniline, widely used for surface coatings, anticorrosive coatings, printing inks, tapes and film coating solvent, and used as reaction solvent, used in electroplating aluminum liquid can be arbitrary control layer thickness and light. Tetrahydrofuran itself can be polycondensation (ring-opening repolymerization initiated by cations) into polytetramethylene ether diol (PTMEG), also known as tetrahydrofuran homopolymer. PTMEG and toluene diisocyanate (TDI) were used to produce special rubber with wear resistance, oil resistance, good low temperature performance and high strength. Block polyether polyester elastic material was prepared with dimethyl terephthalate and 1, 4-butanediol. PTMEG with relative molecular weight of 2000 and p-methylene bis-(4-phenyl) diisocyanate (MDI) are made into polyurethane elastic fiber (SPANDEX fiber), special rubber and some special purpose coatings. In organic synthesis, used for the production of tetrahydrothiophene, 1, 2-dichloroethane,2, 3-dichlorotetrahydrofuran, valerolactone, butanolactone and pyrrolidone. In the pharmaceutical industry, THF is used in the synthesis of cept, rifamycin, progesterone and some hormonal drugs. THF is treated with hydrogen sulfide to produce thiophenol, which can be used as an odorous agent (identification additive) in fuel gas. THF can also be used as a surface treatment agent for synthetic leather.

4. Product details

5. In the earliest industrial production, sugar aldehyde was used as raw material, and the mixture of sugar aldehyde and steam was passed into the reactor filled with zn-Chromium-manganese metal oxide (or palladium) catalyst, and the carbonyl group was removed at 400-420℃to form furan; Tetrahydrofuran was prepared by hydrogenation of furan at 80-120℃using skeleton nickel as catalyst. To produce 1 ton of TETRAhydrofuran by this method, about 3 tons of polysaccharide aldehydes are consumed. There are many kinds of production methods developed later, the industrial method is 1, 4-butanediol catalytic dehydration ring method, because 1, 4-butanediol is prepared by acetylene and formaldehyde, this method is called Reppe method; Using chloroprene monomer chlorbutadiene by-product 1, 4-dichlorobutene production of tetrahydrofuran, known as dichlorobutene method; A catalytic hydrogenation method using maleic anhydride as raw material was developed. There are five production processes for tetrahydrofuran: [1]

6. Furfural method

7. Furan is generated by furfural decarbonyl, and then hydrogenated. This was one of the first industrial methods to produce tetrahydrofuran. Furfural is mainly produced by hydrolysis of corn cobs and other agricultural and sideline products. The law has been phased out because of its serious pollution and adverse effect on large-scale production. [1]

Catalytic hydrogenation of maleic anhydride

9. Maleic anhydride and hydrogen enter the reactor containing nickel catalyst from the bottom, and the ratio of tetrahydrofuran to γ -butyrolactone in the product can be controlled by adjusting the operating parameters. The reaction products and raw hydrogen are cooled to about 50℃and enter the bottom of the washing tower to separate the unreacted hydrogen and gaseous and liquid products. The unreacted hydrogen and gaseous products are recycled to the reactor after washing, and the liquid products are distilled to obtain tetrahydrofuran products. The ratio of γ -butyrolactone to tetrahydrofuran can be adjusted in the range of 0 ~ (5∶1). The one-way conversion of maleic anhydride is 100%, the selectivity of tetrahydrofuran is 85% ~ 95%, and the product content is 99.97%. The process has the characteristics of good catalyst performance, simple process and less investment. [1]

Dehydration cyclization of 1, 4-butanediol

11. The process is as follows: 1087kg 22% sulfuric acid solution is added to the reactor, and 1, 4-butanediol is added at a rate of 110kg/h at 100℃. The top temperature of the tower is maintained at 80℃, and an aqueous solution containing 80% tetrahydrofuran is obtained from the top of the tower at a rate of 110kg/h. After adding 50t of 1, 4-butanediol, about 70kg coke was removed from the reactor. The coke is filtered and the resulting sulfuric acid solution can be reused, with a THF yield of more than 99%. Sulfuric acid is the earliest catalyst used in the industrial production of TETRAhydrofuran, and it is also the most widely used catalyst in the production today. This process technology is mature, relatively simple, low reaction temperature, high yield of TETRAhydrofuran, but sulfuric acid is easy to corrosion equipment, pollution of the environment. [1]

12. Dichloroprene method

13. With 1, 4-dichlorobutene as raw material, through hydrolysis to generate butenediol, and then through catalytic hydrogenation. 1, 4-dichlorobutene is hydrolyzed in sodium hydroxide solution, and butenediol is generated at 110℃. Sodium chloride is removed by centrifugation. The filtrate is concentrated in an evaporative crystallizer to separate the alkali metal carboxylate, and then the high boiling matter is removed in a distillation column. The refined butenediol is sent to the reactor, and nickel is used as catalyst to hydrogenate butenediol into butanediol at 80 ~ 120℃and a certain pressure. After distillation, the butenediol is hydrogenated into the cyclization reactor, and crude TETRAhydrofuran is generated in acidic medium at normal pressure and 120 ~ 140℃. After distillation, dehydration and high boiling matter are removed, and high purity tetrahydrofuran is finally obtained by distillation. This method has the advantages of simple operation, mild condition, high yield, small amount of catalyst and continuous use. [1]

14. Butadiene oxidation method:

15 with butadiene as raw material, the oxidation of furan, and then hydrogenation. This method has been industrialized abroad.

5. Delivery, transportation and services

Operation precautions: closed operation, full ventilation. Operators must be specially trained and strictly abide by the operating procedures. It is recommended that operators wear a filter gas mask (half-mask), safety glasses, antistatic work clothes, and rubber oil-resistant gloves. Keep away from fire and heat source. No smoking in workplace. Use explosion-proof ventilation systems and equipment. Prevent steam leakage into the workplace air. Avoid contact with oxidants, acids and bases. When filling, the flow rate should be controlled, and there is a grounding device to prevent electrostatic accumulation. Handling should be carried lightly to prevent damage to packaging and containers. Equipped with the corresponding variety and quantity of fire fighting equipment and leakage emergency treatment equipment. Empty containers may contain hazardous materials. [1]

Storage matters needing attention: usually goods with polymer inhibitor. Store in a cool, ventilated warehouse. Keep away from fire and heat source. The storage temperature should not exceed 30℃. Packing should be sealed and out of contact with air. It should be stored separately from oxidizer, acid and alkali, and should not be mixed. Explosion-proof lighting and ventilation facilities are adopted. Do not use mechanical equipment and tools that may cause sparks. The storage area shall be equipped with leakage emergency treatment equipment and suitable storage materials.

6.FAQ

1.How many production lines in your factory?

Our company has two production lines.

2. How long is your delivery time?

Around 7 days to 15 days