Chloro- and bromo-fluoro olefin compounds useful as organic rankine cycle working fluids

摘要

Aspects of the present invention are directed to working fluids and their use in processes wherein the working fluids comprise compounds having the structure of formula (I):;
wherein R1, R2, R3, and R4 are each independently selected from the group consisting of: H, F, Cl, Br, and C1-C6 alkyl, at least C6 aryl, at least C3 cycloalkyl, and C6-C15 alkylaryl optionally substituted with at least one F, Cl, or Br, wherein formula (I) contains at least one F and at least one Cl or Br, provided that if any R is Br, then the compound does not have hydrogen. The working fluids are useful in Rankine cycle systems for efficiently converting waste heat generated from industrial processes, such as electric power generation from fuel cells, into mechanical energy or further to electric power. The working fluids of the invention are also useful in equipment employing other thermal energy conversion processes and cycles.

主权项

1. A process for converting thermal energy to mechanical energy in a Rankine cycle comprising:
vaporizing a working fluid with a low grade thermal energy heat source; expanding the resulting vapor and then cooling with a cold heat source to condense the vapor; and pumping the condensed working fluid;
wherein the working fluid comprises at least one compound having the formula (I):wherein R1, R2, R3, and R4 are each independently selected from the group consisting of: H, F, Cl, Br, and C1-C6 alkyl, at least C6 aryl, at least C3 cycloalkyl, and C6-C15 alkylaryl optionally substituted with at least one F, Cl, or Br, wherein formula (I) contains at least one F and at least one Cl or Br, provided that if formula (I) contains Br, then it also contains no hydrogen and wherein at least one of R1, R2, R3, and R4 is methyl, ethyl, or propyl, optionally substituted with at least one F, Cl, or Br.