Azeotrope-like composition containing 1,2-difluoroethylene or 1,1,2-trifluoroethylene and hydrogen fluoride

Patent metadata

Field	Value
Publication number	US-12036491-B2
Application number	US-202117385196-A
Country	US
Kind code	B2
Filing date	Jul 26, 2021
Priority date	Jan 28, 2019
Publication date	Jul 16, 2024
Grant date	Jul 16, 2024

Abstract

This disclosure provides a novel azeotrope-like composition and a separation method using the composition. The disclosure provides an azeotrope-like composition comprising 1,2-difluoroethylene (HFO-1132) and hydrogen fluoride; an azeotrope-like composition comprising 1,1,2-trifluoroethylene (HFO-1123) and hydrogen fluoride; and a separation method of a composition comprising hydrogen fluoride and at least one member selected from the group consisting of trans-1,2-difluoroethylene (HFO-1132(E)), cis-1,2-difluoroethylene (HFO-1132(Z)), and 1,1,2-trifluoroethylene (HFO-1123).

First claim

The invention claimed is:

1. An azeotrope-like composition comprising hydrogen fluoride and 99 mass % or more and less than 100 mass % of 1,2-difluoroethylene (HFO-1132), based on the total amount of HFO-1132 and hydrogen fluoride, defined as 100 mass %, and an additional compound in a total amount of more than 0 mass % and 15 mass % or less based on the entire azeotrope-like composition defined as 100 mass %, the additional compound being at least one member selected from the group consisting of 1,1-difluoroethylene (HFO-1132a), 1,1,2-trifluoroethylene (HFO-1123), fluoromethane (HFC-41), 1,1,2,2-tetrafluoroethane (HFC-134), and 1,1,2-trifluoroethane (HFC-143).

2. The azeotrope-like composition according to claim 1 , wherein the HFO-1132 is trans-1,2-difluoroethylene (HFO-1132(E)).

3. The azeotrope-like composition according to claim 1 , wherein the HFO-1132 is cis-1,2-difluoroethylene (HFO-1132(Z)).

4. An azeotrope-like composition comprising 1,1,2-trifluoroethylene (HFO-1123), hydrogen fluoride, and an additional compound,
the composition comprising the additional compound in a total amount of more than 0 mass % and 1 mass % or less based on the entire azeotrope-like composition defined as 100 mass %.

5. A separation method of a composition consisting of hydrogen fluoride and at least one member selected from the group consisting of trans-1,2-difluoroethylene (HFO-1132(E)), cis-1,2-difluoroethylene (HFO-1132(Z)), and 1,1,2-trifluoroethylene (HFO-1123),
the method comprising steps (a) and (b), and optionally further comprising step (c):
(a) supplying a composition comprising hydrogen fluoride and at least one member selected from the group consisting of HFO-1132(E), HFO-1132(Z), and HFO-1123 to a first distillation column;
(b) obtaining, as a first distillate, an azeotrope-like composition comprising hydrogen fluoride and at least one member selected from the group consisting of HFO-1132(E), HFO-1132(Z), and HFO-1123, and extracting, as a bottom composition of the first distillation column, a composition that is more enriched in either i) at least one member selected from the group consisting of HFO-1132(E), HFO-1132(Z), and HFO-1123, or ii) hydrogen fluoride in terms of the concentration than the supplied composition; and
(c) supplying the first distillate to a second distillation column to perform distillation in the second distillation column under a pressure different from that of the first distillation column.

Assignees

• Daikin Ind Ltd

Inventors

• Takahashi Kazuhiro

Classifications

• C01B7/196

  by distillation · CPC title

• Y02P20/582

  Recycling of unreacted starting or intermediate materials · CPC title

• C07C17/383

  by distillation · CPC title

• B01D3/36 Primary

  Azeotropic distillation · CPC title