Liquid–Liquid Equilibrium Measurements for Model Systems Related to Catalytic Fast Pyrolysis of Biomass

Abstract

We report liquid−liquid mutual solubilities for binary aqueous mixtures involving 2-, 3-, and 4-ethylphenol, 2-, 3-, and 4-methoxyphenol, benzofuran, and 1H-indene for the temperature range (300 < T/K < 360). Measurements in the waterrich phase for (2-ethylphenol + water) and (4-ethylphenol + water) were extended to T = 440 K and T = 380 K, respectively, to facilitate comparison with literature values. Liquid−liquid equilibrium tie-line determinations were made for four ternary systems involving (water + toluene) mixed with a third component: phenol, 3-ethylphenol, 4-methoxyphenol, or 2,4-dimethylphenol. Literature values at higher temperatures are available for the three (ethylphenol + water) systems, and in general, good agreement is seen. The ternary system (water + toluene + phenol) has been studied previously with inconsistent results reported in the literature, and one report is shown to be anomalous. All systems are modeled with the predictive methods NIST-modified-UNIFAC and NIST-COSMO-SAC, with generally good success (i.e., within 0.05 mole fraction) in the temperature range of interest (300 < T/K < 360). This work is part of a larger project on the testing and development of predictive phase equilibrium models for compound types occurring in catalytic fast pyrolysis of biomass, and background information for that project is provided.

Liquid–Liquid Equilibrium of Water + 2-Methoxyphenol + Methyl Isobutyl Ketone and Water + 1,2-Benzenediol + Methyl Isobutyl Ketone at 303.15 K and 328.15 K

“…In addition, the solubility of water in guaiacol is also reported in this work (47.8 g•kg −1 and 52.3 g•kg −1 at 303.15 K and 328.15 K, respectively). These data are in good agreement with those reported by Jasperson et al, 42 which show an increase in water solubility from 42.9 g•kg −1 to 57.8 g•kg −1 as temperature increases from 300 K to 340 K. In addition, the data at 303.15 K reported in this work is also in good agreement with the value reported by Cesari et al 41 (49.8 g•kg −1 at 303.15 K). On the other hand, the values reported by Cesari et al 41 at higher temperatures (e.g., 74.2 g•kg −1 at 323 K) are in disagreement with those reported by Jasperson et al 42 and those in this work.…”

“…At higher temperature, the solubility found in this work (31.6 g·kg –1 at 328.15 K) seems to be slightly higher than that reported by Cesari et al (27.6 g·kg –1 at 323.15 K). On the other hand, the values reported by Jasperson et al, within 39.9 g·kg –1 and 52.6 g·kg –1 for temperatures in the range of (300–360) K, are in disagreement with the above-mentioned data. In addition, the solubility of water in guaiacol is also reported in this work (47.8 g·kg –1 and 52.3 g·kg –1 at 303.15 K and 328.15 K, respectively).…”

Evaluation of experimental and predicted vapor-liquid equilibrium data for systems relevant to biomass fast pyrolysis and catalytic upgrading

“…Thus, any difference between the predicted and experimental pressure significantly exceeding this value would require special attention. A similar limit for the gas-phase mole fractions has been estimated to be close to 0.05 [14] and is supported by the statistical analysis below.…”

“…Phase behavior and related operations need to be strategically employed for the efficient separation of desired species. The significant quantity of water from CFP results in two or three liquid phases upon condensation, as discussed in the previous publication [14]. In addition to postcondensation liquid-liquid separation, vapor-liquid equilibrium (VLE) is also important for any distillation or fractional condensation for separating chemical species.…”

Multiphase Equilibria Modeling of Fast Pyrolysis Bio-Oils. Group Contribution Associating Equation of State Extension to Lignin Monomers and Derivatives

“…Lines: GCA-EOS prediction. Sources of experimental data: (■, ◆) Jasperson et al; (□, ○) Cesari et al …”