Measurement and correlation of the (pressure, density, temperature) relation of carbon dioxide I. The homogeneous gas and liquid regions in the temperature range from 217 K to 340 K at pressures up to 9 MPa

Measurement and correlation of the (p,ρ,T) relation of nitrogen. I. The homogeneous gas and liquid regions in the temperature range from 66 K to 340 K at pressures up to 12 MPa

“…With the exception of the measuring runs of Friedman, (25) Canfield et al, (26) and Crain and Sonntag (28) nearly all data points confirm each other within the experimental uncertainty of this work. In particular, the (p, r, T ) values of Pieperbeck et al, (34) Guo et al, (31) and Duschek et al (7) are in excellent agreement with the new values, mostly to within =5·10 −5 ·r =. (The apparatus used by Pieperbecket al, (34) and Guo et al, (34) is also a ''Two-Sinker-Densimeter'' which was designed by our group (34) especially for density measurements in the gas region; this apparatus is at the laboratories of Ruhrgas AG in Dorsten, Germany.…”

“…This densimeter was developed in order to obtain accurate (p, r, T ) measurements of pure fluids in the homogeneous gas and liquid phase including the critical region and, in particular, the entire (vapour + liquid) coexistence curve. Up to now, comprehensive measurements on methane, (3)(4)(5)(6) carbon dioxide, (7)(8)(9) argon, (10,11) and ethylene (12,13) have been carried out successfully; nitrogen, (14) sulphur hexafluoride, (15) and the refrigerants R12 and R22 (16) have been measured in parts of the fluid region. The design of the densimeter was described in detail in previous papers; (3,6) therefore only the measuring principle is briefly explained here.…”

Solubility of carbon dioxide in polyethylene/titanium dioxide composite under high pressure and temperature

“…(7) were determined by fitting eqs. (6) and (7) Figure 5 shows the fitting results of PVT data of the composite for the case of no CO 2 dissolution. The opened circles represent the estimated by eqs.…”

“…A more detailed description can be found in the literature. [5][6][7]9 Principle of measurement When CO 2 dissolves in polymer, it swells the polymer. Because the degree of swelling is affected by the amount of dissolved CO 2 , the buoyancy caused by the swelling will change in the course of the solubility measurement.…”

“…5,6 Their apparatus, called magnetic suspension balance (MSB), can isolate a sample from the balance and weigh the sample while keeping the sample in a high-temperature and high-pressure chamber. Recently, using the MSB, Sato and co-workers measured the solubility of CO 2 in PS, PP, and HDPE at temperatures ranging from 373 to 473 K and pressures up to 20 MPa.…”