Process for the manufacture of chlorodifluoromethane

[0070]The reaction apparatus and procedure of Comparative Example 1 were used in this example with the following changes. The reactor liquid phase is maintained at the maximum mass that does not cause entrainment and / or flooding of the reactor liquid phase into the reflux column 5 . A brine cooling medium is circulated through the cooling jacket 10 of the condenser 9 and is used to set the reflux ratio of the condenser 9 to be substantially constant during steady state operation of the reactor so that part of the reflux column vapor effluent condenses and forms 2 of the condenser liquid effluent, and have reduced or substantially no CHCl 2 F and CHF 3 containing CHClF 2 and HCl in the condenser vapor effluent. The reflux ratio averaged 1.60 (min 1.41, max 1.79). The temperature of a point within the lower 1 / 3 of the theoretical stage of the reflux column is 41.5°C on average (minimum 37.9°C, maximum 43.4°C). The amount of pentavalent antimony catalyst present in the liqui...

[0077] The reaction apparatus and procedure of Example 1 were used in this example with the following changes. The reflux column of Example 1 was replaced with a cylindrical column of the same dimensions, however, the bottom 1 / 3 of the length of the reflux column contained a packed bed of stainless steel #25 IMTP packed packing (from Norton Chemical Process Products Co., Ohio, USA), The top 2 / 3 of the reflux column contained 18 trays and had no packing. The average reflux ratio was 1.59 (minimum 1.53, maximum 1.99). The temperature of a point within the lower 1 / 3 of the theoretical stage of the reflux column is 45.9°C on average (minimum 36.5°C, maximum 48.7°C). The amount of pentavalent antimony catalyst present in the liquid phase of the reactor averaged 28.4 wt% (minimum 27.6 wt%, maximum 29.2 wt%). CHCl via line 2 to the reactor 3 The / HF feed ratio averaged 2.78 (min 1.71, max 2.95). Reactor pressure measured at the upper end of the reflux column averaged 199.8 psig (...