Preparation of zeolite-coated pervaporation membranes for the integration of reaction and separation

Potential of Pervaporation and Vapor Separation with Water Selective Membranes for an Optimized Production of Biofuels—A Review

“…Some important reviews concerning the types of membrane, reactor configuration and modeling [21,35,[42][43][44][45][46][47][48][49], specific applications, and hybrid processes realized on an industrial scale [50] have been published [1,9,21,[41][42][43]47,[51][52][53][54][55][56]. In a hybrid process, several possibilities exist to implement the PV or VP modules and the membrane separation devices and the reactor can be separated into two units or integrated into a single one [53,55].…”

“…In a hybrid process, several possibilities exist to implement the PV or VP modules and the membrane separation devices and the reactor can be separated into two units or integrated into a single one [53,55]. In Figure 2 some conceptual processes from the literature are shown [53,56]. The stirred batch reactor is the most commonly used for PV and VP studies.…”

Acetals as Possible Diesel Additives

“…3. Active membrane in reactor: when the reaction and separation takes place in the same unit using catalytically active membranes (Bagnell et al, 1993;Peters et al, 2005;Peters et al 2007). With regards to the level of complexity, the first configuration is the simplest one and the last one is the most complex one showing some limitations.…”

“…In 1993 Bagnell et al (Bagnell et al, 1993) studying the esterification of acetic acid with methanol and n-butanol, concluded that catalytically active membranes show higher permselectivities for water at the same or higher flux, compared to when no reaction was taking place within the membrane phase. In 2005 Peters et al (Peters et al, 2005) developed a zeolite-coated pervaporation membrane depositing zeolite H-USY layers on a silica membrane by dip-coating using TEOS and Ludox AS-40 as binder material. This membrane was tested in the esterification reaction between acetic acid and butanol.…”

“…Another important classification concerns the membrane material, with the two main classes being ceramic and polymeric. In esterification processes, where the pervaporation unit is not integrated in the reaction unit, most of the articles report the use of commercial polymeric dehydration membranes (Benedict et al, 2006;Domingues et al, 1999;Sanz & Gmehling, 2006a;Sanz & Gmehling, 2006b), whereas in those processes where the reaction and the separation are combined in one single reactor polymeric, ceramic and polymeric/ceramic membranes are applied (Bagnell et al, 1993;Bernal et al, 2002;Peters et al, 2005;Peters et al, 2007;Zhu et al, 1996). As an example, the acetalization of ethanol with butanal was carried out using the second configuration, i.e., placing a passive membrane in a reactor (Agirre et al, 2011b) showing a good behavior.…”