Vapor-Phase Thermal Conductivity of Binary Mixtures of Cyclopentane and R134a with R365mfc
The thermal conductivity of mixtures of R365mfc (1,1,1,3,3-pentafluorobutane), with R134a (1,1,1,2-tetrafluoroethane) and cyclopentane were measured using a transient hot-wire method, in the pressure range between 0.1013 and 0.7 MPa and temperatures between 311 and 413 K. The composition of the measured mixtures was 93.0% R365mfc + 7.0% R134a (kg/kg), 27.0% R365mfc + 73.0% R134a (kg/kg) and 62.8% R365mfc + 37.2% Cyclopentane (kg/kg). The Wassiljewa mixing rules modified by Mason and Saxena and the Extended Corresponding States Theory were used to correlate and to predict the experimental results obtained, with an average absolute deviation of 1.8 and 10%, respectively.
Aging of Rigid Polyurethane Foams: Thermal Conductivity of N2 and Cyclopentane Gas Mixtures
The thermal conductivity of three mixtures of nitrogen and cyclopentane is measured using a transient hot wire method, at temperatures between 315.14 and 395.89 K, and pressures up to 0.53 MPa. These mixtures are important in the evaluation of the evolution of the thermal insulation capacity of closed-cell polyurethane foams considering their aging during the respective applications’ total life time. The experimental thermal conductivity data are correlated with the Wassiljewa mixing rules as modified by Mason and Saxena, and predicted using extended corresponding states theory (ECST), with an average absolute deviation of 1.1 and 8.9%, respectively. The increase of the nitrogen fraction in cyclopentane-nitrogen mixtures leads to higher thermal conductivity values than has been predicted by ECST using only pure component thermal conductivity data for all measurements.
Thermodynamics on the Carbochlorination of Titanium-bearing Ores
The equilibrium compositions of the multi-component, multi-phase and multi-reaction system of carbochlorination of titanium-bearing ores are calculated with HSC, a computational chemistry software. The thermodynamic equilibrium calculation of the reaction system shows that a complete conversion of titanium-bearing ores is feasible at a temperature near 200oC. At temperatures ranging from 800 to 1600oC, the products of the reaction system are all in gaseous phase. Thermodynamic analysis accords with the industrial practice. The simulated results provide reasonable scientific basis for improving suitable technological conditions of the carbochlorination reduction.