METHOD OF PENTAFLUOROETHANE PRODUCTION Russian patent published in 2017 - IPC C07C17/20 C07C17/10 C07C19/08 C07C19/12 

FIELD: chemistry.

SUBSTANCE: process of preparation of pentafluoroethane involves the synthesis of hydrodifluorotrichloroethane (R 122) by reacting 1,1-difluoroethane with chlorine at elevated temperature and near atmospheric pressure, separating the products of synthesis from hydrogen chloride, isolating the fractions boiling below the boiling point R 122, For chlorination, and the fraction R 122, which is contacted with hydrogen fluoride at a temperature of 320-420°C, a pressure of 0.1-0.5 MPa and a contact time of 10-60 s. The synthesis products of R 122 are washed with water from hydrogen chloride, compressed to 0.12-0.15 Mpa and rectified to give a fraction of the products boiling below R 122 and the R 122 fraction or compressed to 1.2-1.5 MPa and rectified with separating the hydrogen chloride fraction, the fraction of the products boiling below R 122, and the fraction R 122. Pentafluoroethane (R 125) is further purified from impurity R 115.

EFFECT: use of domestic raw materials in production, improvement of the quality of the target product due to additional purification from impurities on catalysts characterized by high stability, high productivity and selectivity.

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