Fluoroketone C2F5C(O)CF(CF3)2 as a Heat Transfer Fluid for Passive and Pumped 2-Phase Applications

C₂F₅C(O)CF(CF₃)₂, a new Fluoroketone (FK) working fluid with an atmospheric boiling point of 49degC and Global Warming Potential (GWP) ~1, is proposed as an alternative to Perfluorocarbons (PFCs) and hydrofluorocarbons (HFCs) for passive and pumped 2-phase systems. Its thermophysical properties are very similar to those of the PFC C₆F₁₄C₂F₅C(O)CF(CF₃)₂ exhibits low acute toxicity and bears a recommended 8-hour exposure guideline of 150 ppmv. Pool boiling experiments conducted with a porous metallic boiling enhancement at P_atm showed h>8 W/cm²-K at >30 W/cm². Metal corrosion and elastomer compatibility testing show the material to be very inert. 120 hour thermal stability tests conducted with C₂F₅C(O)CF(CF₃)₂ at 230degC in sealed glass ampules with copper and aluminum coupons showed purity changes -0.02%. It will hydrolyze in the presence of a separate water phase and the implications of this incompatibility for water-cooled systems require further investigation.