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

作者：Xiaole Chen, Na Li, Chenyang Wu, Linyu Chen, Qulan Zhou · 发表于：Industrial & Engineering Chemistry Research · 年份：2023 · DOI：10.1021/acs.iecr.3c03328 · 被引用次数：9 · 研究领域：Membrane Separation and Gas Transport、Membrane Separation Technologies、Synthesis and properties of polymers

This study presented a newly prepared silicalite-1/polydimethyldiethoxysilane (PDMDES) nanocomposite membrane through the incorporation of nanosized silicalite-1 particles to enhance the pervaporation performance for alcohol recovery from aqueous solutions. Preheating was strategically employed to facilitate the formation of chemical bonds between silicalite-1 and the cross-linking agent vinyltriethoxysilane (VTES), thereby improving the compatibility between silicalite-1 and the PDMDES polymer. Comprehensive characterizations including FT-IR, XRD, TGA, and CA demonstrated a notable increase in hydrophobicity and thermal stability, attributable to the well-incorporated silicalite-1 nanoparticles. FE-SEM observation revealed two distinct cross-sectional morphologies of the nanocomposite membrane: a dense packed structure with uniformly dispersed silicalite-1 nanoparticles within the PDMDES polymer matrix and a loosely accumulated structure where silicalite-1 was adhered by the PDMDES polymer. This phenomenon was linked to the low viscosity of PDMDES during the membrane preparation, which also resulted in the actual loading of silicalite-1 in the prepared nanocomposite membranes being higher than the intended one. The separation performance, influenced by silicalite-1 loading, operating temperature, and feed concentration, was thoroughly evaluated. Accordingly, the separation factor was enhanced by 90% compared to pure PDMDES membrane, and the optimal pervaporation performance ...