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In the production of cyclohexene by benzene hydrogenation, the by-product cyclohexane forms an azeotrope with cyclohexene. For the extraction and distillation of the binary azeotrope (cyclohexene + cyclohexane), the selectivity and relative volatility of 24 different entrainers were compared and the intermolecular interaction forces and interaction energies were analyzed by the DMol3 module of Materials Studio (MS). N, N-dimethylformamide (DMF) was identified as the entrainer, and vapour–liquid equilibrium (VLE) data were measured at atmospheric pressure for the binary system {cyclohexane + cyclohexene} with a temperature range of 354 K to 356 K, the binary system {cyclohexane + DMF} with a temperature range of 354 K to 390 K, and the binary system {cyclohexene + DMF} with a temperature range of 357 K to 421 K. In addition, the thermodynamic consistency of the experimental data was checked using the Wisniak and Van Ness method. The Wilson, NRTL, and UNIQUAC models were used to regress and fit the experimental data to optimize the binary interaction parameters, and the root mean square (RMSD) and average absolute deviation (AAD) values of all models were below 0.01%, indicating that the experimental data provide a basis for the simulation and optimization of the extractive distillation process. [ABSTRACT FROM AUTHOR]

• Test the liquid–liquid balance data of ternary system. • Association analysis of LLE data was conducted using NRTL model. • The values of binary interaction parameters are obtained through data association. The intermolecular forces, interaction energy and charge density were analyzed using the DMol3 module of Materials Studio (MS). • The ability of non-functional groups to recycle acrylic acid wastewater was analyzed. To explore the effective treatment of acrylic acid wastewater, liquid–liquid equilibrium (LLE) data for water + acrylic acid + {n-propyl acetate, n-butyl acetate, n-heptanol, and methyl isopropyl ketone} at 303.2 K and 101.3 kPa were measured respectively. The distribution coefficients (D) and separation factors (S) were used to assess the extraction effectiveness of the four solvents, and the results of the comparative data showed that the D values of the four solvents for acrylic acid ranged from 1.6 to 4.4, and the S values were in the order of n-butyl acetate > n-propyl acetate > MIPK > n-heptanol. The experimental data were fitted by NRTL and UNIQUAC models to obtain the binary interaction parameters, and the obtained above parameters were proved reliable by the mixing surface analysis method of Gibbs energy topology. The root mean square deviation (RMSD) of both models did not exceed 0.0051 and 0.0077, respectively. In addition, σ-profiles analyzed the differences in extraction effects in terms of interactions and interaction energies, and the analyses showed that the theoretical calculations are in agreement with the experimental results. [ABSTRACT FROM AUTHOR]

Wastewater from coking and pharmaceutical processes often contain a significant amount of 2-methylpyridine, which forms an azeotropic mixture with water. Effectively and cleanly separating 2-methylpyridine from wastewater while conserving energy and obtaining high purity products is an urgent challenge. In this study, ternary liquid-liquid equilibrium (LLE) data for the extraction of 2-methylpyridine from wastewater were measured using three distinct solvents at temperatures of 303.2 K, 313.2 K, and 323.2 K. The obtained ternary data were subsequently correlated with thermodynamic models (NRTL and UNIQUAC) to get relevant binary interaction parameters, bridging a gap in Aspen Plus simulations of 2-methylpyridine separation by octanol solvents. Furthermore, the GUI tool was used to validate these parameters and the results confirmed the reliability of the obtained parameters. It was observed that as the temperature increased, the extraction performance of all systems decreased, indicating that elevated temperature are not conducive to the extraction process. Among the various components, iso-octanol showed the highest separation factor indicating better extraction efficiency of 2-methylpyridine. Additionally, this study integrated quantum chemical calculations to reveal the interaction mechanisms between different solvents, 2-methylpyridine, and water at the microscopic level. The computational results indicated that iso-octanol exhibited the most robust binding affinity with 2-methylpyridine, suggesting that iso-octanol has more excellent extraction properties. • The LLE data for the ternary system of water + 2-methylpyridine + solvents were measured at 303.2 K, 313.2 K, and 323.3 K under atmospheric pressures. • The distribution coefficient and separation factor were calculated. • The NRTL and UNIQUAC models were applied to correlate the LLE data. • The binary interaction parameter values were obtained from the data correlation. • The interaction of 2-methylpyridinel between different media was discussed. [ABSTRACT FROM AUTHOR]