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In this work, tubular γ-alumina ultrafiltration membranes have been modified with a sodium alginate/α-alumina suspension based on a modified polyol process in order to be used as forced flow membrane reactors. A C/Cu nanocomposite layer containing Cu nanoparticles of small and uniform size (ca. 14 nm) was deposited and stabilized on the external and internal surface of the membrane. The structural, morphological and gas permeance properties of the obtained catalytic membranes have been studied and their DeNO x performance has been evaluated in flow through mode of operation. NO catalytic abatement evaluation in flow through dead-end mode with 1% NO in N 2 fed from shell to lumen showed high efficiency even at low temperatures and reached 75% at 400 °C. Steady state NO conversion efficiency reached about 30% at 400 °C and heat treatment in He atmosphere at 440 °C revealed the role of NO sorption onto the carbon dressing.

Specific interactions, for example hydrogen bonding, dominate in numerous industrially important polymeric systems, both polymer solutions and blends. Typical cases are water-soluble polymers including biopolymers of special interest to biotechnology (e.g. the system polyethyleneglycol/dextran/water). Furthermore, most polymer blends are non-compatible and the requirement for compatible polymer pairs is often the presence of hydrogen-bonding interactions (e.g. polyvinylchloride/chlorinated polyethylene). In this work we give at first a short, comparative evaluation of existing thermodynamic models suitable for polymeric systems that take into account, explicitly, specific interactions like HB. The range of application of the models in terms of phase equilibria and their specific characteristics (accuracy of calculation, degree of complexity) are discussed. Finally, vapor–liquid equilibria (VLE) calculations for a number of polymer+solvent systems (including five different polymers) with a novel and very promising model are presented. This model is in the form of an equation of state that is (in its general formulation) non-cubic with respect to volume and has separate terms for physical and chemical interactions. The model has recently been proposed and has already been successfully applied to non-polymeric hydrogen-bonding systems (alcohol/water/hydrocarbons). This is the first time that it is extended to polymer solutions.

Prediction of phase equilibrium for multicomponent systems containing associating compounds (e.g., water and alcohols) is essential in a number of engineering applications (e.g., environmental technology, gas hydrate inhibition) and at the same time represents one of the most stringent tests for a thermodynamic model. Conventional models (e.g., cubic equations of state and excess Gibbs free energy models) provide rapid and often reliable estimates of phase equilibrium in many cases but extension to multicomponent systems, especially those containing water is often troublesome. On the other hand, novel association equations of state perform considerably better but are slower compared to conventional models. Furthermore, the extension of several of them to cross-associating systems (e.g., water–alcohols) exhibits problems. In this work, the performance of two well-known conventional models (SRK and NRTL) is compared for multicomponent systems to a recently proposed association equation of state both in terms of accuracy of predictions and timing. The proposed model incorporates the Wertheim chemical association theory (employed previously in models such as SAFT) and the SRK equation. The model is applied in this work to multicomponent systems in such a way that the inclusion of the Wertheim theory does not give execution times much higher than conventional models. The model yields very satisfactory predictions of multicomponent equilibria for aqueous (both vapor–liquid and liquid–liquid equilibria) systems containing methanol, gases and hydrocarbons, which are moreover, as will be demonstrated in this work, considerably better compared to SRK and NRTL.

The Cubic Plus Association Equation of State (CPA EoS) is applied to the prediction of Vapor–Liquid Equilibrium (VLE) and Liquid–Liquid Equilibrium (LLE) in ternary associating mixtures containing water, alcohols and alkanes. The appropriate set of combining rules for the cross-association energy and volume parameters of the EoS is identified by evaluating the performance of four such sets in the correlation of VLE and LLE for water/alcohol mixtures. Using only one interaction parameter per binary mixture, in the physical part of the EoS, CPA gives very satisfactory predictions of ternary VLE and LLE.

Using an extensive database of experimental critical properties for heavy compounds, which have been compiled mostly from recent literature sources, it is shown that the ratio Tc: Pc (critical temperature over critical pressure) can be expressed in terms of the van der Waals surface area (Qw), which is readily available for any compound from the group contributions of Bondi (given also in UNIFAC tables). The proposed correlation is based on the hole theory of Kurata and Isida for n-paraffin liquids, which is mathematically equivalent to Flory's theory of polymer solutions. The method is suitable for medium to high molecular weight compounds with unknown critical constants. For example, if only one of the two critical constants is available, then the proposed generalized equation offers a useful rapid procedure for the estimation of the other critical property for use in corresponding states, and other relevant applications where knowledge of the critical properties is required. Furthermore, the Tc: Pc method can be used in many cases for identifying the most suitable among the existing group contribution methods for estimating the critical properties of heavy and complex compounds for which experimental values are, very often, not available.

A recently developed equation of state, which combines the physical term of the classical SRK EoS with the association term based on the perturbation theory of Wertheim, called the Cubic Plus Association Equation of State (CPA EoS) (Kontogeorgis et al. [1]), is applied to liquid-liquid equilibrium (LLE) calculations in alcohol hydrocarbon mixtures. The CPA EoS performs very well in all cases using the conventional van der Waals one-fluid mixing rules in the parameters of the physical term and a temperature-independent interaction parameter. The performance of the CPA EoS is compared to that of the conventional SRK EoS and UNIFAC models, and with another association model, the ESD EoS of Suresh and Elliott [2]. The CPA EoS gives much better results than the two conventional models and results comparable to those obtained with the ESD model.

The recently developed Cubic-Plus-Association Equation of State (CPA EoS) is extended in this study to binary systems containing one associating compound (alcohol) and an inert one (hydrocarbon). CPA combines the Soave-Redlich-Kwong (SRK) equation of state for the physical part with an association term based on perturbation theory. The classical van der Waals one-fluid mixing rules are used for the attractive and co-volume parameters, α and b, while the extension of the association term to mixtures is rigorous and does not require any mixing rules. Excellent correlation of Vapor-Liquid Equilibria (VLE) is obtained using a small value for the interaction parameter (kij) in the attractive term of the physical part of the equation of state even when it is temperature-independent. CPA yileds much better results than SRK and its performance is similar to that of other association models, like the Anderko EoS, and the more complex SAFT and Simplified SAFT EoS.

A recently developed equation of state-excess Gibbs free energy (EOS/GE) model with the LCVM (linear combination of Vidal and Michelsen) mixing rule, capable of successful VLE prediction in asymmetric systems is applied to the prediction of solubilities of alkenes, ethers, acids, alcohols, and esters in supercritical carbon dioxide. Considering the experimental uncertainties, excellent correlation of binary data and satisfactory prediction of ternary and multicomponent equilibria are obtained in most cases over a wide range of temperature, pressure, and system asymmetry. These promising results render the LCVM model a useful tool for the preliminary design of processes involving mixtures with organic compounds and supercritical carbon dioxide.