IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Carbon dioxide with Ethylene and Poly(methyl methacrylate) (PMMA)

Components:
   (1) Poly(methyl methacrylate) (PMMA); ; [9011-14-7]  NIST Chemistry WebBook for detail
   (2) Carbon dioxide; CO2; [124-38-9]  NIST Chemistry WebBook for detail
   (3) Ethylene; C2H4; [74-85-1]  NIST Chemistry WebBook for detail

Original Measurements:
   E.S. Sanders, W.J. Koros, H.B. Hopfenberg and V. Stannett, J. Membr. Sci. 18, 53 (1984).

Variables:
   Temperature = 308 K
   Pressure = 308 K

Prepared By:
   Yu. P. Yampol'skii

Experimental Remarks:

   The two following figures (Fig. 6 and 7) deal with mixed gas sorption of CO₂ and C₂H₄. Points are experimental data, solid lines are predictions of DMS equation and dashed lines are prediction of equation:

C₁=k_D1p₁++C¹₁b₁p₁/(1+b₁p₁+b₂p₂)

C₂=k_D2p₂++C¹_H2b₂p₂/(1+b₁p₁+b₂p₂).

All the parameters for gases (1) and (2) are pure components sorption parameters from Table 2.

Experimental Data: (Subscripts 1,2,3, ..., in column headings refer to components 1,2,3, ...)

Table 1. Sorption isotherms of pure carbon dioxide and ethylene in PMMA at 308 K (The original data were represented graphically)
Chemical Name	Pressure [MPa]	Sorption [(V₁(STP)/V₃)]
CO2	0.07	2.40
CO2	0.13	4.09
CO2	0.20	5.92
CO2	0.22	6.25
CO2	0.27	7.28
CO2	0.31	8.08
CO2	0.35	8.87
C2H4	0.10	2.16
C2H4	0.16	3.00
C2H4	0.20	3.47
C2H4	0.23	3.80
C2H4	0.27	4.31
C2H4	0.33	4.97
CO2	0.43	9.86
CO2	0.46	10.51
CO2	0.46	10.70
CO2	0.49	10.84
CO2	0.51	11.31
CO2	0.56	12.16
CO2	0.57	12.44
C2H4	0.35	5.20
C2H4	0.39	5.67
C2H4	0.44	6.00
C2H4	0.47	6.47
C2H4	0.54	6.93
C2H4	0.56	7.00
CO2	0.64	13.09
CO2	0.66	13.61
CO2	0.68	13.80
CO2	0.70	14.22
CO2	0.71	14.36
C2H4	0.65	7.82
C2H4	0.73	8.29
C2H4	0.80	9.08
C2H4	0.81	9.13

Table 2. Dual mode sorption parameters for pure carbon dioxide and ethylene in PMMA at 308 K
Chemical Name	Henry's law constant, K [cm³(STP)/cm³ atm]	Langmuir's parameter, C_H [cm³(STP) cm^-3]	Affinity Coefficient b [atm^-1]
CO2, Pressure based parameters	0.916	12.59	0.236
C2H4, Pressure based parameters	0.531	7.09	0.259
CO2, Fugacity based parameters	1.015	11.86	0.243
C2H4, Fugacity based parameters	0.490	8.32	0.217

View Figure 1 for this Evaluation

View Figure 2 for this Evaluation

Method/Apparatus/Procedure:
   Apparatus specifically designed to measure mixed gas sorption was described is Ref. I. It consisted of four chambers: one chamber contained the polymer, three others were used to meter gases accurately (individual or mixtures) into the first one or for sampling gases directly into a gas chromatograph. All chambers were provided with pressure transducers (Gould Model PA 822). The method is based on the concept of maintaining material balance. For both pure gases and mixtures. PVT behaviour was taken into account.

Source and Purity of Materials:
   C0₂: Air Products, purity 99.99 %.
C₂H₄ Airco, purity 99.5 %.
PMMA: Aldrich Chemical Co., M_v = 600 000, glass transition temperature 393 K.

Estimated Errors:

   Temperature: Precision in T: ± 0.01 K.
   Pressure: Relative precision of pressures: ± 0.3 %.

References:
   ¹E. S. Sanders, W. I. Koros, H. B, Hopfenberg, and V. T. Stannett, J. Membr, Sci. 13,161 (1983).