(3-Aminopropyl) Triethoxysilane-Modified ZIF-90 Nanoparticle/Polydimethylsiloxane Mixed Matrix Membranes for Ethanol Recovery via Pervaporation

Abstract

The present study eliminated nonselective defects by amending the MOF-based mixed matrix membrane (MMM) interface with (3-aminopropyl) triethoxysilane (APTES) via Schiff’s base reaction. This modification on the ZIF-90 nanoparticle surfaces enhanced the polydimethylsiloxane (PDMS) matrix interaction in the MMMs. Interfacial defects were then minimized through APTES-ZIF-90 nanoparticle surface alkoxy and PDMS chain hydroxyl group cross-linking. Enhanced chemical interactions between the nanoparticles and the polymeric matrix in the APTES-ZIF-90/PDMS MMMs resulted in higher interface compatibility and separation performance than the ZIF-90 nanoparticle MMMs, which ultimately improved its ethanol affinity and hydrophobicity. When the load of APTES-ZIF-90 nanoparticles was 15% and the temperature was 40 °C, the pervaporation performance of APTES-ZIF-90/PDMS MMMs was optimal, the separation factor was 16.8, and the permeation flux was 223 g/(m2·h). Compared with pure PDMS, the separation factor and permeation flux increased by 91 and 67%, respectively. In addition, stable APTES-ZIF-90/PDMS MMM pervaporation performance was observed after an optimal operation time of 120 h. Overall, the present work presented methods to optimize MOF-based MMMs for enhanced interface morphology and separation performance for ethanol recovery.

pH-Responsive Graphene Oxide-Based 2D/3D Composite for Enhancing Anti-Corrosion Properties of Epoxy Coating

“…For GO, the sharp peak at 9.7° is attributed to the characteristic diffraction peak of the GO (001) crystal plane [ 33 ]. The characteristic diffraction peaks of ZIF–90 can be observed at 7.3°, 14.5° and 17.9°, which are consistent with those of ZIF–90 reported in the literature [ 34 ]. For ZIF–90/GO, the diffraction peaks of ZIF–90 and GO can be detected.…”

High flux and ultra‐thin poly‐dimethyldiethoxysilane/poly(vinylidene fluoride) composite membrane for alcohols recovery from aqueous solution by pervaporation

“…The PV performance of PDMDES composite membrane at different temperatures is illustrated in Figure 12. Inferred from Figure 12A, the total permeation flux through the membrane was greatly enhanced which can be attributed to the increase of free volume and the permeate pressure of mixture, and the permeation of alcohols increased linearly with the temperature increase 57,58 from 30 to 60°C. Thus, the total permeation flux through the membrane was greatly enhanced as from 2.71 to 10.07 kg m −2 h −1 for methanol/water solution and from 2.97 to 10.06 kg m −2 h −1 for ethanol/water solution.…”

Enhancing Pervaporation Performance for Alcohol Recovery from Aqueous Solutions with Silicalite-1/Polydimethyldiethoxysilane (PDMDES) Nanocomposite Membranes

“…A linear relationship with a negative slope was observed for both water and alcohol, suggesting enhanced permeation with increasing temperature, leading to higher flux levels at elevated temperatures. For both the methanol separation and ethanol separation, the E a values for water (36.2 kJ mol –1 for the methanol separation and 35.9 kJ mol –1 for the ethanol separation) were higher than those for alcohol (29.2 kJ mol –1 for methanol and 24.6 kJ mol –1 for ethanol), indicating that the extent of flux increment with elevating temperature of water was larger than that of alcohol when using this nanocomposite membrane for separation, which was also found in other reported results. − This resulted in a reduction in the separation factor at elevated temperatures, suggesting that the newly prepared nanocomposite membrane facilitated the internal transport of water molecules at high temperatures. Therefore, elevated temperatures are not conducive to achieving optimal performance with these membranes.…”