Measurement and Modeling of the Solubility of 9H-Carbazole in Sub- and Supercritical Propane

Abstract

The solubility of 9H-carbazole in sub- and supercritical propane has been measured using a static view cell at pressures from (4.3 to 10.0) MPa and temperatures from (323 to 405) K. The mole fraction of 9H-carbazole varied from 4·10−5 to 4·10−4 over the experimental range studied. The solubility of 9H-carbazole in propane is 1 order of magnitude higher than that of 9H-carbazole in CO2 for similar values of the reduced pressure and temperature, which highlights the excellent solvent properties of propane relative to CO2 for the extraction of polyaromatic compounds. The experimental solubility data were correlated with the Peng−Robinson equation of state using six different sets of mixing rules for the estimation of the mixture parameters a M and b M. Good fits of the experimental results were obtained for all of the mixing rules tested, especially for those involving two adjustable parameters; the absolute average percentage deviation (AAPD) was 16.4 % for the best fit. In addition, the empirical equation of Chrastil was used to model the experimental solubility, and a similar AAPD (16.6 %) was obtained. In this case, because of the simplicity of the empirical model, three adjustable parameters were required for the adjustment. Both of the mathematical expressions evaluated (Peng−Robinson and Chrastil) can be used for the prediction of the solubility of 9H-carbazole in propane.

Compressed isobutane as a solvent of heavy hydrocarbons

“…In equations above a ij and b ij represent the interaction parameters whose calculation is via mixing rules. We have used in this work two sets of mixing rules that yielded good correlation of the experimental results in previous works of our group . They are the Van der Waals set of rules (labeled S1 below), defined for binary mixtures by Eq.…”

“…According to all above, in this article we will report the solubilities of these compounds in isobutane at temperatures between 367 and 413 K and pressures from 3.9 to 7.5 MPa. Following, we will compare the solubility results obtained with isobutane to those reported in the literature for propane and CO 2 . Next, considering that rational process design is entirely dependent on the existence of appropriate thermodynamic models for phase equilibrium calculation at working conditions, the solubility data experimentally obtained will be modeled by the Peng – Robinson equation of state .…”

An Effective Approach for Separating Carbazole and Its Derivates from Coal-Tar-Derived Anthracene Oil Using Ionic Liquids

“…Heteronuclear single quantum coherence (HNSQC) spectra (Figures S5−S7 of the Supporting Information) can show the correlation peak between the 1 H nucleus and 13 C nucleus directly connected to it. With the formation of the complex, 1 H and 13 C NMR chemical shifts (δ) of carbazole moved to the low field with great change in the hydrogen atom of the N−H bond (Δδ 1 = 0.027 ppm) and C−H bond (Δδ 3 = 0.016 ppm).…”

“…Effectively separating carbazole faces a big challenge due to the weaker N−H•••N bond binding energy (13−40 kJ mol −1 ). 10 Carbazole separation methods can be divided into 2 major categories: physical methods (including crystallization, 11 distillation, emulsion liquid membrane, 12 and supercritical fluid extraction 13 ) and chemical methods (sulfuric acid and alkali metal methods). However, high-temperature distillation usually leads to coking.…”

Measurement and Modeling of the Solubility of Tetramethylthiuram Disulfide and 2-Nitrophenyl Disulfide in Compressed Propane

“…In these equations a ij and b ij represent the interaction parameters whose calculation is via mixing rules for which there are different sets reported in the literature. [13][14][15][16]48,49 …”