University of Kentucky
Islam, Mohammad Saiful.
MICROFILTRATION MEMBRANE PORE FUNCTIONALIZATION APPROACHES FOR CHLORO-ORGANIC REMEDIATION TO HEAVY METAL SORPTION.
Degree: 2020, University of Kentucky
Microfiltration polyvinylidene fluoride (PVDF) membranes have distinct advantage for open structure in terms of high internal surface area and ease of access in the pore domain. Functionalization of PVDF membranes with different functional groups (-COOH, -OH, -SH) enables responsive (pH, temperature) properties to membrane, tuning of effective pore size, controlling permeate flux. PVDF microfiltration membrane functionalization with suitable responsive polymer such as poly acrylic acid (PAA) to incorporate carboxyl (-COOH) group enables further modification of functionalized PAA-PVDF membranes for different application ranging from catalysis, bio reactor to heavy metal sorption platform. As a catalytic reactor bed, this PAA-PVDF membranes are very desirable platform for in-situ synthesis of catalytic nanoparticles for conducting a wide range of reactions. As a bio reactor, PAA-PVDF membrane with a net charge have been used to electrostatically immobilize enzymes for conducting catalytic reactions. Functionalization of PVDF membrane also allow for the development of high capacity heavy metal sorbents by modifying existing functional groups (-COOH) to other functional groups (-SH) to adsorb heavy metal cations from contaminated water.
Hydrophilic polymers with carboxylic (-COOH) groups are studied in different functionalization processes especially in preparation of responsive (pH) membranes. To understand the role of membrane pore polymerization condition on the properties of functionalized membrane a systematic study has been conducted, specifically, the effects of polymerization on the membrane mass gain, water permeability, Pd-Fe nanoparticle (NP) loading, of pore functionalized polyvinylidene fluoride (PVDF) membranes. In this study, monomer (acrylic acid (AA)) and cross-linker (N, N′- methylene-bis (acrylamide)) concentrations were varied from 10 to 20 wt% of polymer solution and 0.5-2 mol% of monomer concentration, respectively. Results showed that responsive behavior of membrane could be tuned in terms of water permeability over a range of 270-1 Lm-2 h-1 bar-1, which is a function of water pH. The NP size on the membrane surface was found in the range of 16-23 nm. NP loading was found to vary from 0.21 to 0.94 mg per cm2 of membrane area depending on the variation of available carboxyl groups in membrane pore domain.
The NPs functionalized membranes were then tested as a platform for the degradation of 3,3',4,4',5-pentachlorobiphenyl (PCB 126) and understand the effect of NP loading of the rate of degradation of PCB 126. The observed batch reaction rate (Kobs) for PCB 126 degradation for per mg of catalyst loading was found 0.08-0.1 h-1. Degradation study in convective flow mode shows 98.6% PCB 126 is degraded at a residence time of 46.2 s. The corresponding surface area normalized reaction rate (Ksa) is found about two times higher than Ksa of batch degradation; suggesting elimination of the effect of diffusion resistance for degradation of PCB 126 in convective flow mode operation.
A layer-by-layer approach…
Subjects/Keywords: Microfiltration PVDF Membrane; Nanoparticles; Catalytic Membrane Reactor; Enzyme Immobilized Membrane; Thiol Functionalized Membrane; Hollow Nanoparticles; Membrane Science
to Zotero / EndNote / Reference
APA (6th Edition):
Islam, M. S. (2020). MICROFILTRATION MEMBRANE PORE FUNCTIONALIZATION APPROACHES FOR CHLORO-ORGANIC REMEDIATION TO HEAVY METAL SORPTION. (Doctoral Dissertation). University of Kentucky. Retrieved from https://uknowledge.uky.edu/cme_etds/121
Chicago Manual of Style (16th Edition):
Islam, Mohammad Saiful. “MICROFILTRATION MEMBRANE PORE FUNCTIONALIZATION APPROACHES FOR CHLORO-ORGANIC REMEDIATION TO HEAVY METAL SORPTION.” 2020. Doctoral Dissertation, University of Kentucky. Accessed January 16, 2021.
MLA Handbook (7th Edition):
Islam, Mohammad Saiful. “MICROFILTRATION MEMBRANE PORE FUNCTIONALIZATION APPROACHES FOR CHLORO-ORGANIC REMEDIATION TO HEAVY METAL SORPTION.” 2020. Web. 16 Jan 2021.
Islam MS. MICROFILTRATION MEMBRANE PORE FUNCTIONALIZATION APPROACHES FOR CHLORO-ORGANIC REMEDIATION TO HEAVY METAL SORPTION. [Internet] [Doctoral dissertation]. University of Kentucky; 2020. [cited 2021 Jan 16].
Available from: https://uknowledge.uky.edu/cme_etds/121.
Council of Science Editors:
Islam MS. MICROFILTRATION MEMBRANE PORE FUNCTIONALIZATION APPROACHES FOR CHLORO-ORGANIC REMEDIATION TO HEAVY METAL SORPTION. [Doctoral Dissertation]. University of Kentucky; 2020. Available from: https://uknowledge.uky.edu/cme_etds/121