Engineering Commons^™

Investigation Of Solid Polymeric Hollow Fiber Heat Exchange Devices For Use In Thermally-Driven Desalination Processes, Saskia Christian

Theses

The heat exchange between hot brine (4 wt% NaCl) and cold water as well as between condensing steam and cold water without direct fluid-fluid contact using modules made out of solid polymeric hollow fibers of polypropylene (PP) and polyetheretherketone (PEEK) has been studied. The solid hollow fiber dimensions were 425μm/575μm (ID/OD) for PP and 420μm/570μm (ID/OD) for PEEK. Extensive heat transfer measurements have been performed and the experimentally-determined overall heat transfer coefficients utilized to isolate the wall heat transfer coefficient, the inside heat transfer coefficient and the outside heat transfer coefficient. The heat exchange between hot brine and cold water …

Synthesis And Characterization Of Polymer Nanocomposites, Nirav S. Patel

Theses

Polymer nanocomposites were produced by solution mixing of a commercial flexible acrylic polymer paint, with nanofillers of different size, shape, aspect ratio and purity such as hydrotalcite (HT), sodium montmorillonite (MMT), single wall carbon nanotubes (SWNT) and fullerenes (FUL), at 5 and 10 wt% loading. Structural characteristics and mechanical, thermal and barrier properties of the nanocomposites were characterized by different techniques and compared to those of the unfilled polymer.

The presence of partially exfoliated and intercalated nanoplatelets in the polymer resulted in increased 2% secant tensile modulus, and decreased tensile strength and elongation at break, to different extents. While the …

Evaluation Of Unifac Group Interaction Parameters Usijng Properties Based On Quantum Mechanical Calculations, Hansan Kim

Theses

Current group-contribution methods such as ASOG and UNIFAC are widely used for approximate estimation of mixture behavior but unable to distinguish between isomers. Atoms in Molecules (AIM) theory can solve these problems by using quantum mechanics and computational chemistry to compute atomic contributions to molecular properties and to intermolecular interactions. Rigorously defined properties available through AIM theory and new functional group definitions are used for the UNIFAC model to predict the behavior of various mixtures. Results are presented for various mixtures with nine regressed global parameters to optimize model's predictive capability. The results are also compared to analogous results for …

Evaluation Of Knox Group Contribution Parameters Using Quantum Based Molecular And Group Properties, Myriam Carrillo

Theses

Thermodynamic property prediction through the group contribution methods has been improving. However, the approaches considered in the past present not only limitations on the physical basis but often have restrictions as to certain substances, such as isomers. A new group contribution method is proposed that uses AIM theory, which is based on computational chemistry and quantum mechanics, to overcome these limitations by treating each molecule individually. An evaluation of this method as applied to the Knox model is proposed and analyzed for Vapor Liquid Equilibrium (VLE) of mixtures with the help of nine global parameters that are obtained by correlation. …

Pervaporation Of Water From Solvent Solutions, Richard Manning

Theses

Pervaporation is an emerging membrane technology which has found acceptance as a method for the dehydration of organic solvents.

An existing pervaporation apparatus was modified to accommodate a new type of pervaporation membrane. The instrumentation used with the pervaporation apparatus was upgraded to include a Keithley Data Logger. A HAZOP was carried out on the modified pervaporation apparatus to ensure the apparatus was safe to operate after the modifications were completed.

The pervaporation apparatus was initially tested using screening experiments to verify that changing the operating parameters produced a measurable response which could be recorded. The pervaporation apparatus was successfully …