Lopez successfully defended his Ph.D. dissertation

Engr. Edgar Clyde R. Lopez successfully defended his Ph.D. dissertation entitled "Functional Cyclodextrin Metal-organic Framework Composites: Fundamental Studies and its Application in Wastewater Engineering, March 19, 2024, at the Beta Epsilon Multimedia Hall, Melchor Hall, UP Diliman.

Abstract:

Cyclodextrin metal-organic frameworks (CD-MOFs) are renowned for their high surface area, porosity, and unique supramolecular chemistry, making them promising materials for diverse applications. However, their inherent instability in water has limited their use in aqueous solutions. Here, a novel approach was used by incorporating CD-MOFs into composite beads with polyacrylonitrile (PAN) and polyvinylpyrrolidone (PVP) to enhance stability and expand their utility in water treatment for the first time. The optimization of composite bead composition through design of experiments results in remarkable sorption capacities for cationic and anionic dyes. The optimal composition for Crystal Violet (CV) and Brilliant Blue (BB) removal is PAN = 5.91 wt%, PVP = 1.89 wt%, and CD-MOF = 2.68 wt%, achieving sorption capacities of 50.8109 ± 0.0634 mg/g and 28.5583 ± 0.1296 mg/g, respectively. Meanwhile, the removal of Congo Red (CR) and Methylene Blue (MB) is optimized at PAN = 6.96 wt.%, PVP = 2.20 wt.%, and CD-MOF = 2.88 wt%, yielding sorption capacities of MB 37.40 mg/g and CR 18.42 mg/g. Methyl orange is effectively removed with a sorption capacity of 6.56 mg/g at PAN = 4.10 wt.%, PVP = 3.07 wt.%, and CD-MOF = 2.00 wt%. The results of molecular modeling indicate significant interactions between dye and CD-MOF while molecular dynamics calculations demonstrate the kinetic stability of the dye-CD-MOF structures. The composite beads exhibit similar efficacy with other adsorbents, showcasing the potential for industrial-scale application. Nevertheless, further investigations, particularly mechanistic and regeneration studies, are essential to fully harness the PAN/PVP/CD-MOF composite beads' capabilities in removing various pollutants from water. Overall, the incorporation of CD-MOFs into a stable polymeric matrix demonstrates their potential as effective adsorbents for wastewater treatment. Additionally, the study highlights the environmentally friendly nature of this composite material, emphasizing the use of green precursors in CD-MOF synthesis, which enhances its appeal for sustainable adsorption applications.