Most of the analytical instruments require reliable calibration standards for the accurate quantitative determination. The raw materials of these calibration standards are mainly high purity materials whose purities are determined by the SI traceable primary method. Freezing point depression method is one of the primary methods for the determination of the purity traceable to the SI without any reference materials. We introduced an adiabatic calorimeter for this freezing point depression method. We have determined the purity of some high purity organic compounds with this adiabatic calorimeter, and supplied as CRMs with certified value of purity.