Process for producing 2, 3, 3, 3-tetrafluoropropene and 1, 1-difluoroethylene
View Patent ↗To provide an economically advantageous process for producing HFO-1234yf useful as a new refrigerant in sufficiently high yield by one reaction involving thermal decomposition. A process for producing HFO-1234yf and VdF from raw material containing R22, R40 and TFE, by a synthetic reaction involving thermal decomposition, which comprises (a) a step of supplying the R22, the R40 and the TFE to a reactor, as preliminarily mixed or separately, (b) a step of supplying a heat medium to the reactor, and (c) a step of bringing the heat medium in contact with the R22, the R40 and the TFE in the reactor to form the HFO-1234yf and the VdF.
1. A process for producing 2,3,3,3-tetrafluoropropene and 1,1-difluoroethylene from chlorodifluoromethane, chloromethane and tetrafluoroethylene, the process comprising:
(a) supplying chlorodifluoromethane, chloromethane and tetrafluoroethylene to a reactor, as preliminarily mixed or separately,
(b) supplying a heat medium to the reactor, and
(c) contacting the heat medium with chlorodifluoromethane, chloromethane and tetrafluoroethylene in the reactor to form a reaction product comprising 2,3,3,3-tetrafluoropropene and 1,1-difluoroethylene.
2. The process according to claim 1 , wherein a molar ratio of tetrafluoroethylene to chlorodifluoromethane supplied to the reactor ranges from 0.01 to 100.
3. The process according to claim 1 , wherein a molar ratio of chloromethane to chlorodifluoromethane and tetrafluoroethylene in total supplied to the reactor ranges from 0.1 to 10.
4. The process according to claim 1 , wherein chloromethane is supplied to the reactor at a temperature of from 0 to 1,200° C.
5. The process according to claim 1 , wherein chlorodifluoromethane is supplied to the reactor at a temperature of from 0 to 600° C.
6. The process according to claim 1 , wherein tetrafluoroethylene is supplied to the reactor at a temperature of from 0 to 1,200° C.
7. The process according to claim 1 , wherein a temperature in the reactor in said contacting (c) is adjusted to be from 400 to 1,200° C.
8. The process according to claim 1 , wherein the heat medium is supplied to the reactor at a temperature of from 100 to 1,200° C.
9. The process according to claim 1 , wherein the heat medium is at least one selected from the group consisting of steam, nitrogen and carbon dioxide.
10. The process according to claim 1 , wherein the heat medium is supplied at an amount of from 20 to 98 vol % in an entire gas supplied to the reactor.
11. The process according to claim 1 , wherein gas supplied to the reactor has a contact time in the reactor of from 0.01 to 10 seconds.
12. The process according to claim 1 , wherein a pressure in the reactor is from 0 to 2 MPa by gauge pressure.
13. The process according to claim 1 , wherein at least one selected from the group consisting of chlorotrifluoroethylene, trifluoroethylene, hexafluoropropene and octafluorocyclobutane, is further supplied to the reactor.
14. The process according to claim 1 , wherein
the reaction product further comprises chlorotrifluoroethylene, and
a molar ratio of 2,3,3,3-tetrafluoropropene to chlorotrifluoroethylene in the reaction product is ≧9.0.
15. The process according to claim 1 , further comprising:
(d) after said contacting (c), withdrawing from the reactor a reaction mixture comprising 2,3,3,3-tetrafluoropropene and 1,1-difluoroethylene formed in the reactor,
wherein said supplying (a), said supplying (b), and said withdrawing (d) are continuously carried out.