The paper contains a status report on an international project coordinated by the Subcommittee on Transport Properties of Conamissiort 1.2 of the International Union of Pure and Applied Chemistry. The project has been conducted to investigate the large discrepancies between the results reported by various authors Ibr the transport properties of RI34a. The project has involved the remeasurenaent of the transport properties of a single sample of R I34a in rdne laboratories throughout the world in order to test the hypothesis that at least part of the discrepancy could be attributed to the purity of Ihe sample. This paper provides an intercomparison of the new experimental results obtained to data in this project Ibr the viscosity and the thermal conductivity in both gaseous and liquid phases. The agreclncnt between the viscosity data from the laboratories contributing to the prc, jcct was improved with several techniques, now producirtg consistent results. This suggests that the purity of the samples of R I34a used in previous work was at least partly rcponsible Ibr the discrepancies observed. For the thermal conductivity in the liquid phasc the resuhs of the measurenlents are also more cortsistenl than before, although nut Ibr all experimental techniques. Nut all of the previous measurements suffered from ~ Invited paper presented at the Twelfth Symposium on Tllermophysical Properties. significant sample impurities, so Ihe present measurements on a consistent high-purity sample can be used to detect data sets v,,hich are outliers, possibly because of impurities. Identification of laboratories and techniques with systematic differences may require the examination of data Ibr several Iluids. The implications for future measurements of the transport properties of other refrigerants are significant.

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The density for mixtures of ethylenediamine (EDA) and water at a pressure of 0.2 MPa have been measured with a vibrating tube densitometer at temperatures in the range (283 to 353) K. The entire composition range was covered with intervals of molar fractions of 10 %. The excess volume has a minimum at a molar fraction of water of 59 %. The variation with temperature in excess volume is small, whereas the temperature variation in density is complex. The temperature dependence in density is well described by combining a Redlich-Kister model for excess volume, without temperature-dependent parameters, with models for the pure component densities.

Glycerol can be synthesized to make 1,3-dinitroglycerin as an intermediate product to produce polyglycidyl nitrate. This study performed kinetic modeling of nitration used elementary reactions that consisting of seven reversible reactions. The aim of this present work is to find out the representing reaction of seven reactions tested. The concept work is to study the reaction rates and its relation to the position of the nitrated hydroxyl group in the molecule. Nitration of glycerol to 1,3-dinitroglycerin was studied in the temperature range 10-30 °C, the molar ratio of nitric acid to glycerol 1/1 to 7/1 and nitric acid concentration of 69%. The seven reaction terms represent the reactions that occurred in the nitration of glycerol. The position of hydroxyl group in molecule causes difference reaction rate. The primary hydroxyl group is more reactive than secondary hydroxyl group. The parameter values describe that the 1 st , 3 rd , 5 th and 7 th reaction rates are very fast. On the contrary, the 2 nd , 4 th and 6 th reaction rates are slow.

The temperature and the composition of the vapor and liquid phases at equilibrium were measured at atmospheric pressure and (50 and 20) kPa for the binary mixtures: water (1) and ethylenediamine (2, EDA); water and ethylethylenediamine (3, EtEDA); and EDA and EtEDA. For the ternary mixture of water, EDA, and EtEDA, equilibrium conditions were measured at atmospheric pressure. The vapor pressure of EtEDA was measured in the temperature range from (358 to 402) K, and Antoine parameters were fitted to the data. Parameters for the universal quasichemical (UNIQUAC) equation are estimated from binary data and applied to the ternary mixture. It was shown that the mixture of EDA and EtEDA has a zeotropic pinch close to pure EDA. Furthermore, it was found that the ternary mixture has a saddle point azeotrope at a molar fraction of 0.24 of water, 0.62 of EDA, and 0.14 of EtEDA and a temperature of 392.6 K at atmospheric pressure. Thus, the volatility between EDA and EtEDA is reversed in the water-rich region, and EtEDA is the most volatile component close to the binary azeotrope between water and EDA. This is illustrated by univolatility lines in a ternary diagram.