Process of separating pentafluoroethane and process of producing pentafluoroethane using the same

A process of producing pentafluoroethane which comprises the steps of:

• (1) reacting perchloroethylene and hydrogen fluoride under pentafluoroethane producing conditions to obtain a gas mixture which comprises components including at least perchloroethylene, pentafluoroethane, hydrogen chloride, dichlorotrifluoroethane, tetrafluorochloroethane and hydrogen fluoride,
• (2) passing the gas mixture through a first condensation stage to obtain a first liquid phase which contains, as a main component, perchloroethylene contained in the gas mixture and a first vapor phase which contains the other components of the gas mixture,
• (3) passing the first vapor phase through a second condensation stage to obtain a second vapor phase which contains pentafluoroethane and hydrogen chloride as main components and a second liquid phase which contains the other components of the first vapor phase,
• (4) introducing the second liquid phase to a distillation stage to separate the second liquid phase into a top fraction which contains mainly pentafluoroethane and hydrogen chloride as main components and a bottom fraction which is substantially free from pentafluoroethane and hydrogen chloride and which contains the other components of the second liquid phase, and
• (5) removing hydrogen chloride from the second vapor phase and the top fraction of the second liquid phase to obtain pentafluoroethane,
• wherein the second liquid phase at the step (3) does not separate into immiscible liquid phases.

A process of producing pentafluoroethane which comprises the steps of:

• (1) reacting perchloroethylene and hydrogen fluoride under pentafluoroethane producing conditions to obtain a gas mixture which comprises components including at least perchloroethylene, pentafluoroethane, hydrogen chloride, dichlorotrifluoroethane, tetrafluorochloroethane and hydrogen fluoride,
• (2) passing the gas mixture through a first condensation stage to obtain a first liquid phase which contains, as a main component, perchloroethylene contained in the gas mixture and a first vapor phase which contains the other components of the gas mixture,
• (3) introducing the first vapor phase to a distillation stage to separate the first vapor phase into a ton fraction which contains mainly pentafluoroethane and hydrogen chloride as main components and a bottom fraction which is substantially free from pentafluoroethane and hydrogen chloride and which contains the other components of the first vapor phase, and
• (4) removing hydrogen chloride from the top fraction to obtain pentafluoroethane.