摘要:
The invention relates to a process for the manufacture of 1-chloro-1,1-difluoroethane in the liquid phase by reacting hydrofluoric acid with 1,1,1-trichloroethane and/or 1,1-dichloro-1-fluoroethane.The selectively is improved by using a perfluoroalkanesulphonic acid, in particular trifluoromethanesulphonic acid, as a catalyst.
摘要:
In order to remove the impurities (in particular 1-chloro-2,2-difluoroethylene) present in crude 1,1,1,2-tetrafluoroethane (F134a), a gaseous mixture of crude F134a and hydrofluoric acid is treated in the gas phase, in the presence of a fluorination catalyst, at a temperature of between 200 and 380° C. and under a pressure between atmospheric pressure and 2.5 MPa, the HF/F134a molar ratio being between 0.05 and 0.5.
摘要:
The invention relates to the manufacture of difluoromethane by catalytic gas-phase fluorination of methylene chloride.The operation is carried out in the presence of oxygen at a temperature of between 330 and 450.degree. C. and with a bulk or supported chromium catalyst.
摘要:
In order to purify a crude pentafluoroethane (F125) containing chloropentafluoroethane (F115), it is subjected to a heat treatment in the presence of hydrogen, the treatment being carried out at a temperature at least equal to 550.degree. C. and with an H.sub.2 /F115 molar ratio of at least 10.
摘要:
To recover the antimony contained in a solution of use antimony-containing catalyst, emananting from units for the fluorination or chlorofluorination of halogenated hydrocarbons comprising at least two carbon atoms, the solution is concentrated to the limit of distillation of antimony trichloride, an excess of chlorine is then added to convert SbCl.sub.3 to SbCl.sub.5, and SbCl.sub.5 is distilled under reduced pressure without exceeding 120.degree. C.The recoverd antimony pentachloride is sufficiently pure to be able to be recycled directly to the fluorination reactor.
摘要:
1,1,1,3,3-Pentachlorobutane, whose fluorination leads to 1,1,1,3,3-pentafluorobutane, is prepared with high yield and selectivity by addition of carbon tetrachloride to 2-chloropropene in the presence of a copper salt and an amine.
摘要:
To remove the traces of chlorotrifluoroethylene (F1113) which are present in a pentafluoroethane (F125), the F125 is passed through a bed of active carbon.
摘要:
Novel 2,2-bis(2-perfluoroalkylethylthio)acetaldehydes having the formula: ##STR1## wherein R.sub.F and R'.sub.F are the same or different perfluoroalkyl groups, together with processes for producing the same and using the same to prepare surface active agents and products with hydrophobic and lipophobic properties.
摘要:
Demoisturizing composition used for the displacement of liquid water, comprising a chlorofluorocarbon that is liquid at room temperature, containing a surface-active agent responding to the formula: ##STR1## in which R is an alkyl group in C.sub.6 -C.sub.18R' is an alkyl group in C.sub.1 to C.sub.2R" is an alkyl group in C.sub.1 to C.sub.18p is a value ranging between 1 and 2characterized in that the surface-active composition is prepared by mixing the following three constituents: ##STR2## where R.sub.F represents a straight or branched perfluorinated alkyl chain of formula C.sub.q F.sub.2q+1 in which q is a whole number ranging between 2 and 20 and where X is a divalent bond group that may be partially halogenated and R.sub.1 and R.sub.2 represent a hydrogen atom, an alkyl radical or a hydroxyalkyl radical, containing less than 6 carbon atoms.
摘要:
To remove the olefinic impurities from a hydrochlorofluoroethane of formula: CF.sub.3 --CHClX (X=H, F, or Cl), it is subjected to a photochlorination stage.