Método de análisis de un hidrofluoroalcano

Método de análisis del contenido de impurezas orgánicas de un hidrofluoroalcano de calidad farmacéutica seleccionado de 1,1,1,2,3,3,3-heptafluoropropano, 1,1,1,3,3-pentafluoropropano, 1,1,1,3,3- pentafluorobutano y 1,1,1,2-tetrafluoroetano en el que el hidrofluoroalcano presenta un contenido individual de cada impureza orgánica como máximo de 8 ppm molar, y en el que a) se somete el hidrofluoroalcano a una operación de cromatografía de gases en el que la fase estacionaria comprende al menos un polialquilsiloxano funcionalizado mediante grupos polares de tipo nitrilo y; b) se efectúa una operación de detección de impurezas orgánicas mediante espectrometría de masas en el que el método de detección se selecciona del modo de ion seleccionado (selected ion monitoring (SIM)) o el modo de tiempo de vuelo (time of flight (TOF)). A process comprises subjecting 1, 1, 1, 2 - tetrafluoroethane containing organic impurities to at least two distillations. A process comprises subjecting 1, 1, 1, 2 - tetrafluoroethane containing organic impurities to at least two distillations, where the second is conducted under higher pressure than the first one; and separated at the exit from the second distillation process. At least one fraction comprises hydrofluoroalkane, free from organic impurities. Independent claims are also included for: (1) use of 1, 1, 1, 2 - tetrafluoroethane purified by process as claimed as propulsive gas for pharmaceutical aerosols; (2) a method for analysis of organic impurities level of hydro-fluoroalkane comprising gas chromatography conducted at initial temperature up to 40[deg]C (preferably up to (-20)[deg]C), and detection of impurities by mass spectrometry, using SIM (selected ion monitoring) or TOF (time of flight) mode; (3) a process for production of hydrofluoroalkane, using purification process and method of analysis as claimed as means of quality control; (4) a process for producing pharmaceutical aerosols containing at least one hydrofluoroalkane of pharmaceutical quality, using quality control method as claimed; (5) production of purified hydrofluoroalkane selected from 1, 1, 1, 2, 3, 3, 3 - heptafluoropropane, 1, 1, 1, 3, 3 - pentafluoro-propane and 1, 1, 1, 3, 3 - pentafluorobutane, using 2-stage distillation process as claimed; and (6) purified hydrofluoroalkane with molar content of each organic impurity below 10 ppm.