Measurement and modeling of the solubility of CO2 and N2 in a model resin system based on resin from spruce wood (Picea abies (L))

In this thermodynamic description of phase behavior between CO2, N2 and wood resin, the resin from spruce wood has been represented by a model system composed of three main components from the resin (oleic acid, α-pinene and abietic acid). A new simple experimental equipment for the determination of gas solubility in substances with high stickiness and viscosity at sub- and super-critical conditions is presented.

New solubility data for N2 in α-pinene, for CO2 and N2 in oleic acid, and for CO2+N2 mixtures in a model resin mixture at the temperatures 298 K and 318 K and in the pressure range 20–148 bar are presented. The experimental solubility's data were used to estimate the interaction parameters for the modified Huron–Vidal first-order model, MHV1, for parameters not included in the earlier work.

In addition, the binary interaction parameters for the remaining binaries estimated in the earlier work were used to evaluate the vapor liquid equilibrium (VLE) of the binary systems. However, the predictions of the model for some of the binary systems were not satisfactory and these parameters were re-estimated on the basis of binary data from the literature.

The results predicted by the MHV1-model for the solubility of CO2 and N2 in the model resin show that the model can qualitatively describe the CO2N2-resin mixtures. Both the temperature dependence and the composition changes are described well.