Tetrahydrofuran,CAS 109-99-9

Tetrahydrofuran (THF) is an industrial solvent widely recognized for its unique combination of useful properties. DuPont THF is better than 99.9% pure with a small (0.025-0.040 wt % ) amount of butylated hydroxytoluene (BHT, 4-methyl-2,6-di-tertbutyl phenol) added as an antioxidant. Tetrahydrofuran is a cycloaliphatic ether and is not ''photochemically reactive'' as defined in Section k of Los Angeles County's Rule 66 (equivalent to Rule 442 of the Southern California Air Pollution Control Dist

Tetrahydrofuran (THF) is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specifically a cyclic ether. It is a colorless, water-miscible organic liquid with low viscosity. It is mainly used as a precursor to polymers. Being polar and having a wide liquid range, THF is a versatile solvent.

Tetrahydrofuran Use and Manufacturing
Methods of Manufacturing
Tetrahydrofuran production process has the following.
(1) furfural method from furfural decarbonylation of furan, and hydrogenation derived. This is one of the first methods in the industry to produce tetrahydrofuran. Furfural mainly by the corn and other agricultural and sideline products hydrolysis manufacturing. The law of pollution is not conducive to large-scale production, has been gradually eliminated.
(2) maleic anhydride catalytic hydrogenation maleic anhydride and hydrogen from the bottom into the reactor containing nickel catalyst, the product of tetrahydrofuran and γ-butyrolactone ratio can be controlled by adjusting the operating parameters. The reaction product and the raw material hydrogen are cooled to about 50 ° C into the bottom of the scrubber so that the unreacted hydrogen gas and the gaseous state are separated from the liquid product. The unreacted hydrogen and gaseous products are washed and circulated to the reactor, and the liquid product is distilled to obtain the tetrahydrofuran product The The process can be 0 ~ (5: 1) within the range of any adjustment of γ-butyrolactone and tetrahydrofuran ratio, maleic anhydride one-way conversion rate of 100%, tetrahydrofuran selectivity of 85% to 95%, product content of 99.97%. The process has the characteristics of good catalyst performance, simple process, low investment and so on.
(3) 1, 4-butanediol dehydration cyclization process is: adding 1087kg 22% sulfuric acid aqueous solution to the reactor, adding 1, 4-butanediol at 110 ℃ / h at 100 ℃, the tower The top temperature was maintained at 80 ° C and an aqueous solution containing 80% tetrahydrofuran was obtained from the top of the column at a rate of about 110 kg / h. After addition of 50 t 1, 4-butanediol, about 70 kg of the mass was removed from the reactor. The filtrate is filtered and the resulting aqueous sulfuric acid solution can be reused, and the yield of tetrahydrofuran in this process can reach more than 99%. Sulfuric acid is the first catalyst used in the industrial production of tetrahydrofuran and is the catalyst used in today's production. This technology is mature, the process is relatively simple, the reaction temperature is low, the yield of tetrahydrofuran is higher, but the sulfuric acid corrosion equipment, pollute the environment.
(4) dichlorobutene method to 1, 4-dichlorobutylene as raw material, the hydrolysis of butylene glycol, and then by catalytic hydrogenation derived. 1, 4-dichlorobutene in sodium hydroxide solution hydrolysis, 110 ° C to produce butylene glycol, centrifugal separation of sodium chloride, the filtrate in the evaporative mold concentration, separation of alkali metal carboxylate, and then in the The distillation column removes the high boiling material. The refined butene diol was fed into the reactor, and the reaction was carried out at 80 to 120 ° C under a certain pressure. The butylene glycol was hydrogenated to form butanediol and distilled into the cyclization reactor. And 120 ~ 140 ° C in the acidic medium to produce crude tetrahydrofuran, distillation dehydration and de-high boiling, and finally distilled high purity tetrahydrofuran. This method is simple, mild conditions, high yield, less catalyst, can be used continuously.
(5) butadiene oxidation method to butadiene as raw material, the oxidation of furan, and then hydrogen derived. This law has been industrialized abroad.
(6) Industrial production The first sugar aldehyde as raw material, the mixture of aldehyde and steam into the filling zinc - chromium - manganese metal oxide (or palladium) catalyst reactor, at 400-420 ° C off the carbonyl group into furan And then tetrahydrofuran was prepared by hydrogenation of furan at 80-120 ° C with skeleton nickel as catalyst. The method produces 1 ton of tetrahydrofuran, about 3 tons of polysaccharide consumption. There are many kinds of production methods, the industrialization of 1, 4-butanediol catalytic dehydration ring method, because butanediol is made from acetylene and formaldehyde, this method known as lei method (Reppe method); use Chloroprene rubber monomer chloroprene by-product 1, 4-dichlorobutene production of tetrahydrofuran, known as dichlorobutene method; in recent years the development of maleic anhydride as the raw material of catalytic hydrogenation.
(7) in the presence of zinc oxide, chromium oxide, manganese dioxide, furfural can be catalyzed by deacetalization, and in the presence of nickel-aluminum catalyst hydrogenation of tetrahydrofuran

Uses
Solvent for high polymer like polyvinyl chloride. As reaction medium for grignard & metal hydride reactions. In the synthesis of butyrolactone, succinic acid, 1,4-butanediol diacetate. Solvent in histological techniques and reverse phase hplc.