摘要:
A method and a device for purifying 1,4-bis(bromodifluoromethyl)benzene are disclosed. In order to solve the problem of hard to purify and separate 1,4-bis(bromodifluoromethyl)benzene crude products, diphenylmethane that has a higher boiling point and does not interact with 1,4-bis(bromodifluoromethyl)benzene is mixed with the 1,4-bis(bromodifluoromethyl)benzene crude products for evaporation. Afterwards, the purity of the vaporized product is detected and only that reaching an expected purity is collected to obtain high-purity 1,4-bis(bromodifluoromethyl)benzene.
摘要:
A process for producing 1,1,1-trifluoroethane (HFC-143a) which process comprises reacting hydrogen fluoride with vinylidene chloride along with one or more of 1,1,-dichloro-1-fluoroethane (HCFC-141b), 1-chloro-1,1-difluoroethane (HCFC-142b) and 1,1,1-trichloroethane (HCC-140a) in the presence of pentavalent antimony as a fluorination catalyst under conditions to produce 1,1,1-trifluoroethane (HFC-143a), generally in yields of 90% or more.
摘要:
A convenient and economical process for the preparation of 1,1-dichloro-3,3,3-trifluoropropane (HCFC-243) by the reaction of 1,1,1,3,3-pentachloropropane (HCC-240) with hydrogen fluoride in the presence of an activated hydrofluorination catalyst. Also, the selective fluorination of hydrochlorocarbons and/or hydrochlorofluorocarbons, or mixtures thereof is shown. A HCFC-243 reaction product yield of greater than 40% is obtained.
摘要:
The dehydrochlorination of 1,1,2,3,3-pentachloropropane to produce 1,2,3,3-tetrachloropropene is conducted using aqueous alkali metal hydroxide in the substantial absence of added ethanol. The 1,2,3,3-tetrachloropropene is recovered from the reaction mixture in the substantial absence of added ether. The preferred methods of recovery are steam distillation and flash distillation.
摘要:
Fullerenes are selectively functionalized by adsorbing fullerene molecules on molecular sieves such as zeolites as the first step in a desired functionalizing reaction and then adding functional groups or compounds to the fullerenes within the molecular sieves. An improved reactor for fullerene material is thereby available. Selectively functionalized fullerenes formed in accordance with the invention can also serve as precursors for further selectively functionalized products.
摘要:
In this process for recovering noble metals of group VIII from a contaminated catalyst solution originating from the carbonylation of methyl acetate and/or dimethylether (the catalyst solution containing carbonyl complexes of these noble metals, organic or inorganic promoters, undistillable organic contaminants as well as volatiles) the volatiles are distillatively removed from the catalyst solution and the remaining distillation residue is water-treated, whereby the noble metal/carbonyl-complex is precipitated together with the organic contaminants and is separated from the aqueous phase, while the promotor is dissolved and recovered in conventional manner. The noble metals are then set free in elemental form by subjecting the noble metal/carbonyl-complex separated and contaminated with organic polymers at temperatures of 150.degree. to 300.degree. C. to treatment with an ethyleneglycoldialkylether solvent of the formula R(--OCH.sub.2 --CH.sub.2).sub.n --OR, in which n stands for a number of from 1 to 4 and R stands for identical or different alkyl groups having from 1 to 6 carbon atoms. The noble metal can then be recovered by filtration, and the solvent can be freed of organic contaminants by distillation.
摘要:
A process for reducing the chloride concentration in a system which contains an ethylenically unsaturated chlorinated hydrocarbon, water and HCl which includes providing certain nitrogen-containing compounds in the system and contacting the system with a molecular sieve. The process surprisingly is capable of regenerating the nitrogen-containing compounds employed.
摘要:
In accordance with the present invention, the process for preparing allyl chloride comprises chlorination of propylene with hydrogen chloride in an upward stream consisting of propylene, hydrogen chloride and a catalyst, i.e. manganese dioxide incorporated in a leaned manganese ore in an amount of 20 to 35% byu weight at a temperature within the range of from 300.degree. to 500.degree. C., concentration of the catalyst in the stream of 130-180 kg/m.sup.3, time of contact between propylene, hydrogen chloride and the catalyst in the stream of 0.2-0.7 sec and a volume ratio between propylene and hydrogen chloride in the stream of 1:3-5 respectively. Then the spent catalyst is separated from the reaction mixture resulting from chlorination, regenerated with oxygen at a temperature of from 500.degree. to 520.degree. C. and recycled to the chlorination process. The process according to the present invention makes it possible to achieve a yield of allyl chloride of up to 81.5 vol. % as calculated for the passed propylene, conversion of propylene of up to 98.0% at a process selectivity of from 80 to 85 vol. %. Furthermore, the process according to the present invention makes it possible to provide a wasteless production of allyl chloride.
摘要:
Increased selectivity to vinylidene chloride is obtained in the catalytic vapor phase dehydrochlorination of 1,1,2-trichloroethane by conducting the reaction in the presence of a cesium nitrate catalyst.
摘要:
A melt oxychlorination process which produces trichloroethylene and perchloroethylene by chlorinating C.sub.2 hydrocarbons and their incompletely chlorinated derivatives containing at least 50% by weight of 1,1,2-trichloroethane, dichloroethylene, or both together, with a melt consisting essentially of iron chloride, copper chloride and alkali metal chloride by dispersing the material to be chlorinated in the melt whereby said material is chlorinated by the melt, wherein certain alkali metal chlorides, proportions thereof, and process conditions are utilized to provide desired product selectivity.