Bubble Point Measurements of Three Binary Mixtures of Refrigerants: R-32/1234yf, R-32/1234ze(E) and R-1132a/1234yf.

Bubble point pressures of three binary mixtures at two compositions each have been measured utilizing a static method. The mixtures studied were: difluoromethane + 2,3,3,3 tetrafluoroprop-1-ene (R-32/1234yf), difluoromethane + (E)-1,3,3,3-tetrafluoroprop-1-ene (R-32/1234ze(E)) and 1,1-difluororethene + 2,3,3,3 tetrafluoroprop-1-ene (R-1132a/1234yf). For all the mixtures the minimum temperature measured was 270 K.

Bubble Point Measurements of Mixtures of HFO and HFC Refrigerants.

Bubble point pressures of six binary mixtures at two compositions each have been measured utilizing a static method. The performance of the apparatus was characterized from bubble point measurements of R32 + R125 for which 19 literature studies are available for comparison. The mixtures studied were as follow: R1234yf + R134a, R134a + R1234ze (E), R1234yf + R1234ze (E), R125 + R1234yf, R1234ze (E) + R227ea and R1234yf + R152a.

Compressed-liquid Densities of the Binary Mixture Dimethyl Carbonate + Heptane at Three Compositions.

Compressed-liquid densities of the binary system dimethyl carbonate + heptane have been measured with a vibrating-tube densimeter over the temperature and pressure ranges of 270 K to 470 K, and 1 MPa to 50 MPa at three compositions of the mixture. The measurements are part of an effort to better understand the molecular interactions of polar/non-polar mixtures. These types of mixtures often exhibit very non-ideal behavior.

Calibration Fluids and Calibration Equations: How Choices May Affect the Results of Density Measurements Made with U-Tube Densimeters.

Data on the calibration fluids water and toluene individually, and the combination of those two sets of data, were correlated with two different equations (resulting in six sets of calibration equation parameters) to analyze data measured with a vibrating-tube densimeter on the lubricants pentaerythritol tetrapentanoate (POE5), pentaerythritol tetraheptanoate (POE7), and pentaerythritol tetranonanoate (POE9) at temperatures from 270 K to 470 K and pressures from 0.5 MPa to 50 MPa. The objective was to explore how the calculated densities of the lubricants would differ based on the calibration equations and calibration fluid(s).

Density measurements of compressed-liquid dimethyl ether + pentane mixtures.

Compressed-liquid densities of three compositions of the binary mixture dimethyl ether (CAS No. 115-10-6) + pentane (CAS No. 109-66-0) have been measured with a vibrating U-tube densimeter.

Bubble-Point Measurements of -Propane + -Decane Binary Mixtures with Comparisons of Binary Mixture Interaction Parameters for Linear Alkanes.

To develop comprehensive models for multicomponent natural gas mixtures, it is necessary to have binary interaction parameters for each of the pairs of constituent fluids that form the mixture. The determination of accurate mixture interaction parameters depends on reliably collected experimental data. In this work, we have carried out an experimental campaign to measure the bubble-point pressures of mixtures of -propane and -decane, a mixture that has been thus far poorly studied with only four existing data sets.

A Small-Volume Apparatus for the Measurement of Phase Equilibria.

An apparatus has been designed and constructed for the measurement of vapor-liquid equilibrium properties. The main components of the apparatus consist of an equilibrium cell and a vapor circulation pump. The cell and all of the system valves are housed inside a temperature controlled, insulated aluminum block.