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MWW family of different structural types (MCM-22, MCM-49, MCM-56 and MCM-36) was used as catalysts for aldol condensation of furfural and acetone studied in a batch reactor at 100 °C, autogenous pressure and a reaction time of 0-4 h. To establish a relation between physico-chemical and catalytic properties of microporous materials, the samples were characterized by XRD, SEM, N2 adsorption, FTIR and TGA. It was found that the acidic solids possessed appreciable activity in the reaction and resulted in the formation of products of aldehyde-ketone interaction. Surprisingly, MCM-22 and MCM-49, i.e. three-dimensional materials containing internal supercages, exhibited higher activity than two MCM-36 catalysts with two-dimensional character having larger accessible external surface area due to expansion of the interlayer space by swelling and pillaring treatments. Moreover, all MWW family catalysts gave higher conversion than the large-pore zeolite BEA. Nevertheless, furfural conversion decreased rapidly for all the studied materials due to coke formation. Unexpectedly, the deactivation was found to be more severe for MCM-36 catalysts than for MCM-22 and MCM-49, which was attributed to the reaction taking place also in supercages that are protected by 10-ring channels from severe coking. In contrast the cups located on the external surface were coked rapidly.

The Peng−Robinson (PR) and cubic-plus-association (CPA) equations of state are used to predict the phase behavior and solubility of CO 2 and normal alkanes from C 1 to nC 10 in several bitumens. Both of the equations of state are investigated over wide ranges of temperature and pressure. The results show that the PR-EOS describes mixure of bitumens with CO 2 and alkanes when there is no second liquid phase or when the asphaltene content in the second liquid phase is not high. The CPA-EOS describes the phase behavior of mixtures of bitumens and CO 2 and alkanes in liquid−liquid states even when the asphaltene content of one of the phases is high. High asphaltene content results in significant association and cross-association where the CPA-EOS is a natural choice. In this work the only adjustable parameter in the CPA-EOS is the cross-association energy parameter, and we show that the solubility of CO 2 and alkanes in bitumens is usually not sensitive to this parameter. However, in two-phase liquid−liquid and three-phase liquid−liquid−vapor states with one phase having a high concentration of asphaltenes, the results become sensitive to the cross-association energy parameter.