三價鋁金屬與二價可大量合成之MOF對於揮發性有機物的除去效能比較

Abstract

論文透過高孔洞性金屬有機骨架(Metal-Organic Frameworks, MOFs)與其高分子混摻顆粒進行揮發性有機物在不同的測試下的吸附效率。所選擇的MOFs包含了可大量合成的二價金屬MOFs : HKUST-1、ZIF-8；具有中心金屬含氧鍊狀結構的鋁三價MOFs : MIL-68、A520及CAU-10等，進一步將多種MOFs進行和高分子聚乙烯醇(PVA)進行混摻，找出孔隙率最佳的比例進行揮發性有機物的吸附測試。在性質的鑑定上，以粉末X-ray繞射鑑定混摻後的MOF@PVA高分子顆粒和所使用的MOF比較繞射圖譜結構差異；傅立葉轉換紅外線光譜儀(FTIR)測試MOFs與PVA高分子是否有配位或鍵結產生官能基；場發射式掃描電子顯微鏡(FE-SEM)進行混摻顆粒橫切面的微觀觀察；熱重分析儀(TGA)測定顆粒以及粉體的結構穩定性。結果成功配置出10%、20%、30% PVA/MOF混摻比例的高分子顆粒，且10% MIL-68@PVA 10%顆粒有著高達0.86 g/g的醋酸、0.62 g/g的丙酮、0.53 g/g的異丙醇及0.7 g/g的甲苯氣體吸附量，對比於市售的活性碳、沸石吸附劑都有著1.5~3倍的吸附優越性，同時擁有極佳的循環使用效率。而在低濃度的甲苯動態吸附測試結果中，10% HKUST-1@PVA顆粒卻有著比10% MIL-68@PVA顆粒更好的甲苯吸附效率，總吸附量接近3倍差距，並且透過動力學模型的模擬成功找出了較適合解釋在低濃度動態下微孔MOFs對甲苯的吸附機理，表明在高濃度甲苯環境如工廠中更適合以MIL-68@PVA顆粒作為吸附劑，而低濃度工業及家庭廢氣則更適合小孔徑的HKUST-1@PVA。This paper mainly uses Metal-Organic Frameworks (MOFs) and PVA mixed with MOFs particles for testing their ability inVolatile Organic Compounds (VOCs) adsorption capacity. The selected MOFs include divalent metal MOFs that can be synthesized in large quantities: HKUST-1 and ZIF-8; aluminum trivalent MOFs with a central metal oxygen-containing chain structure : MIL-68, A520 and CAU-10. A variety of MOFs were mixed with polymer polyvinyl alcohol (PVA) to find out the best ratio for the adsorption test of volatile organic compounds. In the identification of properties, powder X-ray diffraction (PXRD) was used to identify the difference in the diffraction pattern between the MOF powder and MOF@PVA Beads; Fourier transform infrared spectroscopy (FTIR) tested whether new functional group produced by interaction between MOFs and PVA; field emission scanning electron microscope (FE-SEM) was used for observating the cross-section of mixed particles and the thermogravimetric Analyzer (TGA) measures the structural stability of particles and powders. As a result, MOF@PVA Beads with 10%, 20%, and 30% PVA/MOF blending ratios were successfully configured, and the 10% MIL-68@PVA particles have up to 0.86 g/g of acetic acid, 0.62 g/g of acetone, 0.53 g/g of isopropanol and 0.7 g/g of toluene gas adsorption capacity, at least 1.5~3 times better than commercially available activated carbon and zeolite adsorbents and has excellent recycling efficiency.In the low concentration of toluene dynamic adsorption test results, 10% HKUST-1@PVA Beads have a better toluene adsorption efficiency than 10% MIL-68@PVA up to 3 times gap. Through the simulation of the kinetic model, we found that it is more suitable to explain the adsorption mechanism of toluene by the microporous MOFs under the low concentration dynamic.