Membrane Science Commons^™

Nanometer-Scale Membrane Electrode Systems For Active Protein Separation, Enzyme Immobilization And Cellular Electroporation, Zhiqiang Chen

Theses and Dissertations--Chemical and Materials Engineering

Automated and continuous processes are the future trends in downstream protein purification. A functionalized nanometer-scale membrane electrode system, mimicking the function of cell wall transporters, can selectively capture genetically modified proteins and subsequently pump them through the system under programmed voltage pulses. Numerical study of the two-step pulse pumping cycles coupled with experimental His-GFP releasing study reveals the optimal 14s/1s pumping/repel pulse pumping condition at 10 mM bulk imidazole concentration in the permeate side. A separation factor for GFP: BSA of 9.7 was achieved with observed GFP electrophoretic mobility of 3.1×10^-6 cm² s^-1 V^-1 at 10 …

Iron And Iron Oxide Functionalized Membranes With Applications To Selected Chloro-Organic And Metal Removal From Water, Minghui Gui

Theses and Dissertations--Chemical and Materials Engineering

The development of functionalized membranes with tunable pores and catalytic properties provides us an opportunity to manipulate the membrane pore structure, selectivity and reactivity. By introducing the functional groups into membrane pores, dissolved metal ions and reactive particles can be effectively immobilized within the polymer matrix for toxic chloro-organic and heavy metal remediation in water.

A polyelectrolyte functionalized membrane platform with tunable pore size and ion exchange capacity has been developed for iron/iron oxide nano-catalyst synthesis and chlorinated organic compound (trichloroethylene, TCE and polychlorinated biphenyls, PCBs) degradation. Highly robust polyvinylidene fluoride (PVDF) microfiltration membranes are used as the support with …

Layer-By-Layer Assemblies For Membrane-Based Enzymatic Catalysis, Andrew R. Tomaino

Theses and Dissertations--Chemical and Materials Engineering

While considerable progress has been made towards understanding the effect that membrane-based layer-by-layer (LbL) immobilizations have on the activity and stability of enzymatic catalysis, detailed work is required in order to fundamentally quantify and optimize the functionalization and operating conditions that define these properties. This work aims to probe deeper into the nature of transport mechanisms by use of pressure-induced, flow-driven enzymatic catalysis of LbL-functionalized hydrophilized poly(vinyldiene) (PVDF)-poly(acrylic acid) (PAA)-poly(allylamine hydrochloride) (PAH)-glucose oxidase (GOx) membranes. These membranes were coupled in a sealed series following cellulose acetate (CA) membranes for the elimination of product accumulation within the feed-side solution during operation. …

Membrane Immobilized Reactive Fe/Pd Nanoparticles: Modeling And Tce Degradation Results, Ruo He

Theses and Dissertations--Chemical and Materials Engineering

Detoxification of chlorinated organic compound is an important and urgent issue in water remediation nowadays. Trichloroethylene (TCE), as a model compound in this study, has been proved to be degraded effectively by bimetallic nanoparticles (NPs) in solution phase. In this study, Fe/Pd bimetallic NPs were synthesized in poly (acrylic acid) (PAA) functionalized polyvinylidene fluoride (PVDF) microfiltration membranes. TCE dechlorination with these bimetallic NPs was conducted under different pH values and different metal loadings to study the role of corrosion on reaction rates.

One-dimensional mathematical model with pseudo first-order reaction kinetic was introduced to discuss the TCE dechlorination profile in membrane …