“Low GWP” HFO refrigerants R1234yf and R1234ze(E)

The ban on the use of R134a in mobile air-conditioning systems within the EU has triggered a series of research projects. Apart from the CO2 technology (page 35), new refrigerants with very low GWP values and similar thermodynamic properties as R134a have been developed.

In early 2006, two refrigerant mixtures were introduced under the names „Blend H“ (Honeywell) and „DP-1“ (DuPont). INEOS Fluor followed with another version under the trade name AC-1. In the broadest sense, all of these refrigerants were blends of various fluorinated molecules.

During the development and test phase it became obvious that not all acceptance criteria could be met, and thus further examinations with these blends were discontinued. Consequently, DuPont (meanwhile Chemours) and Honeywell bundled their research and development activities in a joint venture which focused on 2,3,3,3-tetrafluoropropene (CF3CF=CH2). This refrigerant, designated R1234yf, belongs to the group of hydro fluoro olefins (HFO). These refrigerants are unsaturated HFCs with a chemical double bond. Read more