Modeling vapor liquid equilibrium of ionic liquids + gas binary systems at high pressure with cubic equations of state

Abstract

-Ionic liquids (IL) have been described as novel environmentally benign solvents because of their remarkable characteristics. Numerous applications of these solvents continue to grow at an exponential rate. In this work, high pressure vapor liquid equilibria for 17 different IL + gas binary systems were modeled at different temperatures with Peng-Robinson (PR) and Soave-Redlich-Kwong (SRK) equations of state, combined with the van der Waals mixing rule with two binary interaction parameters (vdW-2). The experimental data were taken from the literature. The optimum binary interaction parameters were estimated by minimization of an objective function based on the average absolute relative deviation of liquid and vapor phases, using the modified Simplex algorithm. The solubilities of all gases studied in this work decrease as the temperature increases and increase with increasing pressure. The correlated results were highly satisfactory, with average absolute relative deviations of 2.10% and 2.25% for PR-vdW-2 and SRK-vdW-2, respectively.

Use of CO2 as a co-reactant to promote syngas production in supercritical water gasification of sugarcane bagasse

“…Similar thermic trends are reported in previous works of our group [6,7] who reported slightly exothermic behavior in thermodynamic evaluation of SCWG of glucose, cellulose and microalgae biomass when CO 2 was added as co-reactant. In these works the effect of CH 4 addition as co-reactant was discussed too, the authors emphasize that the addition of CH 4 resulted in significant increases in hydrogen production.…”

“…The Gibbs energy minimization and entropy maximization models were previously validated with both experimental and simulated data for the SCWG of microalgae biomass [6], for the SCWG of glucose and cellulose [7], for the oxidative reforming of methane [13] and for SCWG of glycerol and microalgae biomass from Spirulina sp. [18].…”

“…The obtained H 2 /CO molar ratio was discussed and the aspects of CO 2 addition in the reaction behavior were discussed with focus on obtained product composition. The addition of CO 2 as coreactant in SCWG reactions was previously studied by our group [6,7] but in none of these papers the behavior of CO 2 in the system are studied extensively, as done in this paper. Fig.…”

“…The entropy was determined using the chemical potential of each component in the mixture and the chemical potential can be determined using the previous presented Eqs. (5) and (6). So the total entropy can be expressed as follows: …”

“…These methodologies and considerations were applied in previous works of our research group with good predictive results for similar systems like as SCWG of microalgae biomass [6], glucose and cellulose [7] and oxidative reforming of methane [13].…”