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In the recent decades, due to environmental sustainability, abundance, availability and appropriate thermo-physical properties, natural refrigerants are being considered with potential of substitute refrigerants. In this study, Propylene (R1270), Propane (R290), Isobutane (R600a), R407c, R410a, R12, R22 and R134a have been investigated as refrigerant in common refrigeration systems. In the case studies, the thermodynamic and technical parameters of the cycle, using above mentioned refrigerants, have been investigated for common refrigeration systems in temperature range of -30°C to 10°C in the evaporator, and also for heat pump systems with a temperature range of 45°C to 60°C in the condenser. Finally, Propylene was introduced as a refrigerant to replace with synthetic refrigerants in the above mentioned temperature ranges in common refrigeration cycles.