The prediction of phase equilibria for hydrocarbon/water blends in separators, is a subject of considerable importance for chemical processes. Despite its relevance, there are still pending questions. Among them, is the prediction of the correct number of phases. While a stability analysis using the Gibbs Free Energy of mixing and the NRTL model, provide a good understanding with calculation issues, when using HYSYS V9 and Aspen Plus V9 software, this shows that significant phase equilibrium uncertainties still exist. To clarify these matters, n-octane and water blends, are good surrogates of naphtha/water mixtures. Runs were developed in a CREC vapor–liquid (VL_ Cell operated with octane–water mixtures under dynamic conditions and used to establish the two-phase (liquid–vapor) and three phase (liquid–liquid–vapor) domains. Results obtained demonstrate that the two phase region (full solubility in the liquid phase) of n-octane in water at 100 °C is in the 10-4 mol fraction range, and it is larger than the 10-5 mol fraction predicted by Aspen Plus and the 10-7 mol fraction reported in the technical literature. Furthermore, and to provide an effective and accurate method for predicting the number of phases, a machine learning (ML) technique was implemented and successfully demonstrated, in the present study.

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This work describes vapour pressure measurements of a water/synthetic naphtha mixture using a dynamic CREC-VL-Cell, designed to obtain reliable vapour measurements (P v sat,i ). The CREC-VL-Cell is used to measure vapour pressures for immiscible or partially miscible liquids, given its high multiphase mixing capability. Runs in the CREC-VL-Cell involve a dynamic method, operating with a set heating ramp, with continuous tracking of both saturation vapour pressure and temperature within the cell. This system allows for the establishment equilibrium vapour pressures, in a recommended 50-120 C range, emulating the conditions of the naphtha recovery in oil sand processes.Results obtained in the CREC-VL-Cell at 1080 rpm are validated using data from Aspen-Hysys with a Peng-Robinson fluid package for pure octane and water. On the other hand, using a 2.5 wt.% and 4 wt.% synthetic naphtha in 97.5 wt.% water blend, experimental data shows partial agreement with the Aspen-Hysys Peng-Robinson fluid package predictions, demonstrating the value of the experimental vapour-liquid-liquid (VLL) data obtained in the CREC-VL-Cell.

Bitumen is extracted from oil sands using warm water and additives. The resulting bitumen froth is diluted with naphtha in a froth treatment process. Residual naphtha in the aqueous tailings of the froth treatment unit is recovered in a naphtha recovery unit (NRU). It is imperative to maximize the naphtha recovery process to minimize the plant's environmental and economic impact. It is, in this respect, that NRU vapour–liquid–liquid equilibrium data is of significant value. In this work, a paraffinic‐aromatic synthetic naphtha (PASN) with a true boiling point (TBP) similar to that of froth treatment naphtha is used. Water/PASN mixtures are studied using the Soave‐Redlich‐Kwong equation of state with a Kabadi‐Danner modification. The tangent plane distance (TPD) is evaluated as a possible criterion to calculate the number of phases, with its significant shortcomings being established. As well, experimental data obtained in a CREC‐VL‐Cell is observed to display higher solubilities of PASN in water than the ones obtained by HYSYS‐Aspen Plus V9 simulation. To address these issues, a machine learning (ML)‐based phase classification methodology was considered, predicting the number of phases with a 99% recall. This anticipates that ML will be of significant value for faster convergence of the flash split calculations for the naphtha hydrocarbon‐water systems under consideration.

A B S T R A C TDesign guidelines were applied for the production of methyl acetate in a pervaporation membrane reactor. The limits of operation were determined. The shift in equilibrium is evaluated by a simple model involving simultaneously chemical equilibrium and transport across the membrane. This analysis establishes possibilities and limitations of a pervaporation membrane reactor. The performance of a continuous stirred tank reactor with a pervaporation membrane (PV-CSTR) is analyzed. To achieve conversions higher than 90%, conditions must satisfy D a > 150 and 0.01 < P e < 100. Increasing temperature has a negative effect on membrane reactor conversion. The effect of sweep is important at high-permeate pressures. Two design charts were created to illustrate dynamics between permeation rates, reaction rates, and selectivity with conversion. The three powerful tools proposed for the analysis of a pervaporation membrane reactor described the system in a systematic way.