1,1,1,2,3-PENTAFLUOROPROPANE synthesis

Yield:431-31-2 91.3 %Chromat.

Reaction Conditions:

with cobalt(II) fuoride;fluorine at 250;Inert atmosphere;Large scale;Concentration;Temperature;

Steps:

12 Experimental Examples 10 to 13

A total of 48 kg of CoF₂ was added into the reactor and the regenerator, the angle of the blades attached to the paddles was adjusted, and the number of rotations of the screws of each conveyor was adjusted so that a transfer rate of CoF₂ reached 48 kg/hr. Thereafter, internal temperatures of the reactor and the regenerator were increased by allowing nitrogen to flow in the reactor and the regenerator (flow rate of 2 L/min to 15 L/min), thereby removing moisture in CoF₂. When the moisture in CoF₂ was completely removed, the internal temperatures of the reactor and the regenerator were maintained respectively to a temperature of 250 °C while gradually decreasing a flow rate of nitrogen to 2 L/min. First, a fluorine gas was added to the regenerator at a rate of 0.94 kg/hr for 3 hours, and the addition of the fluorine gas was then suspended. A catalyst was rotated for 1 hour, the fluorine gas was added again at a rate of 0.94 kg/hr for 30 minutes, and the source gas, HFO-1243zf (CF₃CH=CH₂), was added to the reactor at a rate of 2.45 kg/hr. A fluorination temperature of the regenerator was constantly maintained at 250 °C. An initial molar ratio between CoF₃ and CoF₂ was adjusted by changing an addition time (3 hours, 2 hours and 1 hour) of an initial fluorine gas without adding the source gas (1243zf) when CoF₂ was filled to 100%. When the change in initial molar ratio between CoF₃ and CoF₂ (3/7-->2/8-->1/9) and the change in operation conditions were performed, HFP (CF₃CF=CF₃) was added to completely convert CoF₃ into CoF₂ and a reaction system was purged with nitrogen, and thus the changes were carried out under a condition in which CoF₂ was filled to 100% at the beginning. [0096] Table 2 lists ratios of products at a cobalt fluoride flow rate of 48 kg/hr according to changes in reaction temperature of the reactor and composition ratio of initial CoF₃/CoF₂, as analyzed using GC. As listed in Table 2, it could be seen that a ratio of the produced 1,1,1,2,3-pentafluoropropane (HFC-245eb) was increased at the same reaction temperature with a decrease in molar ratio between CoF₃ and CoF₂. Also, it could be seen that a ratio of the produced HFC-245eb was increased at the same molar ratio between CoF₃ and CoF₂ with an increase in reaction temperature. Experimental Examples 10 to 13 were carried out in the same manner as in Experimental Examples 1 to 9, except that a total of 96 kg of CoF₂ was added to each of the reactor and the regenerator. [0099] The following Table 3 lists ratios of products at a cobalt fluoride flow rate of 96 kg/hr according to changes in reaction temperature of the reactor and composition ratio of initial CoF₃/CoF₂, as analyzed using GC. As listed in Table 3, it could be seen that the 245eb had a high yield of 80% or more, which exceeded those of Experimental Examples 1 to 9, at all the reaction temperatures compared with those listed in Table 2 (1 mole of a source gas: 10 moles of CoF₃/CoF₂-containing cobalt fluoride). Also, the entire amount of the catalyst was decreased, based on 1 mole of the source gas (1243zf), but the molar ratio between CoF₃ and CoF₂ was decreased, compared with those of Experimental Examples 1 to 9. As a result, it could be seen that the selectivity to 245eb was shown to be very excellent.

References:

EP2733135,2014,A1 Location in patent:Paragraph 0095-0099