University of Twente Student Theses


The Influences of Hydrogel Geometry on the Desalination of Salt Water

Derckx, E.G.H (2017) The Influences of Hydrogel Geometry on the Desalination of Salt Water.

[img] PDF
Abstract:In this bachelor's thesis, the in uences of geometry on ion transport on a patterned membrane stack from researchers from SFI and BIOS (MESA+ from University of Twente) are investigated. Three geometries were used with different properties regarding shape, aspect ratio and exchange area: A linear shaped ('full'), a coned shaped ('tilted') and a H-patterned ('original') shape. The relative efficiencies of these three geometries have been investigated using amperometry. Mi- croscopic observations were used to quantify the vortex generation (as a result of electroconvection) in each geometry. It has been found that the 'tilted' shaped membrane stack is the most efficient, using amperometry with 8 volt. Concentration profiling and vortex generation measurements have indicated that the 'original' shaped membrane stack has the highest capability to generate vortices in the system compared to the other two geometries, due to its multiple sites for vortices to nucleate from. Specifically, it has been suggested that the vortex size affects the desalination rate as suggested by two cases that show the extremes of vortex generation (in the presence of an optimum present. Case 1: Where there is over-mixing when turbulent convection generated from the vortices limit the directional movement of ions towards the membrane, limiting the transfer rate. This is due to the vortex size being bigger than the channel width. Case 2: A lower vortex size could increase mixing properties between membranes while the depletion zone decreases.
Item Type:Essay (Bachelor)
Faculty:TNW: Science and Technology
Subject:35 chemistry
Programme:Chemical Engineering BSc (56960)
Link to this item:
Export this item as:BibTeX
HTML Citation
Reference Manager


Repository Staff Only: item control page