Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Fouling behavior of microstructured hollow fibers in cross-flow filtrations: Critical flux determination and direct visual observation of particle deposition
Date
2011-04-15
Author
Çulfaz Emecen, Pınar Zeynep
Wessling, M.
Lammertink, R.G.H.
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
192
views
0
downloads
Cite This
The fouling behavior of microstructured hollow fiber membranes was investigated in cross-flow filtrations of colloidal silica and yeast. In addition to the as-fabricated microstructured fibers, twisted fibers made by twisting the microstructured fibers around their own axes were tested and compared to round fibers. In silica filtrations, the three different fibers showed similar behavior and increasing Reynolds number increased the critical fluxes significantly. In yeast filtrations, the twisted fiber performed similar to the round fiber and better than the structured fiber. Among the three fibers, during yeast filtrations the critical flux for irreversibility was highest for the twisted fiber. The Reynolds number had little effect on the critical fluxes for particle deposition, which was attributed to the strong adsorption of yeast particles on the membrane. On the other hand, the critical fluxes for irreversibility increased with increasing Reynolds number for all three fibers. Direct visual observation of yeast particles on the surface of the three different hollow fibers revealed that for the structured and twisted fibers, the initial deposition rate on the fins is much lower than that in the grooves. This is attributed to the shear-induced migration of the yeast particles from areas of high shear (fins) to those of low shear (grooves). Furthermore, on the fins of the twisted fiber the deposition rate was lower than that on the fins of the structured fiber. This observation, together with the observed high critical fluxes for the twisted fiber led to the conclusion that the twisting induces a secondary flow in the liquid. This secondary flow is effective in depolarizing the buildup of micron-sized yeast particles since the diffusion of these particles is strongly effected by gradients in shear rate. On the other hand, for the silica colloids which are much smaller, shear-induced diffusion is not significant and twisting does not have an improving effect on filtration.
Subject Keywords
Physical and Theoretical Chemistry
,
Filtration and Separation
,
General Materials Science
,
Biochemistry
URI
https://hdl.handle.net/11511/39744
Journal
Journal of Membrane Science
DOI
https://doi.org/10.1016/j.memsci.2011.02.002
Collections
Department of Chemical Engineering, Article
Suggestions
OpenMETU
Core
Fouling behavior of microstructured hollow fiber membranes in dead-end filtrations: Critical flux determination and NMR imaging of particle deposition
Çulfaz Emecen, Pınar Zeynep; Utiu, Lavinia; Kueppers, Markus; Bluemich, Bernhard; Melin, Thomas; Wessling, Matthias; Lammertink, Rob G. H. (2011-03-01)
The fouling behavior of microstructured hollow fibers was investigated in constant flux filtrations of colloidal silica and sodium alginate. It was observed that the fouling resistance increases faster with structured fibers than with round fibers. Reversibility of structured fibers' fouling was similar during silica filtrations and better in sodium alginate filtrations when compared with round fibers. The deposition of two different silica sols on the membranes was observed by NMR imaging. The sols had dif...
Helical hollow fibers via rope coiling: Effect of spinning conditions on geometry and membrane morphology
Yucel, Hazal; Çulfaz Emecen, Pınar Zeynep (Elsevier BV, 2018-08-01)
Helical hollow fiber membranes from poly(ether sulfone) were spun via dry-wet spinning, making use of the liquid rope coiling phenomenon. The polymer solution composition was changed by varying the coagulation value and adding PEG400 as pore former. The bore liquid composition, outer coagulation bath temperature, air gap, polymer dope and bore liquid flowrates were varied to map the conditions where helical fibers form. It was observed that increasing air gap changed fiber geometry from straight to helical....
Polycarbonate-polypyrrole mixed matrix gas separation membranes
Hacarlioglu, P; Toppare, Levent Kamil; Yılmaz, Levent (Elsevier BV, 2003-11-01)
The gas separation properties of the polycarbonate-polypyrrole mixed matrix membranes were evaluated based on the introduction of conducting polymer as powder fillers. The electrically conductive fillers are obtained from two main synthesis routes namely electrochemical and chemical methods. The permeation properties of polycarbonate-polypyrrole systems are highly dependent on the synthesis method (electrochemical or chemical) and also the membrane casting conditions (casting solvent type). The introduction...
Fouling behavior of microstructured hollow fiber membranes in submerged and aerated filtrations
Çulfaz Emecen, Pınar Zeynep; Lammertink, R.G.H. (2011-02-01)
The performance of microstructured hollow fiber membranes in submerged and aerated systems was investigated using colloidal silica as a model foulant. The microstructured fibers were compared to round fibers and to twisted microstructured fibers in flux-stepping experiments. The fouling resistances in the structured fibers were found to be higher than those of round fibers. This was attributed to stagnant zones in the grooves of the structured fibers. As the bubble sizes were larger than the size of the gro...
Development of enhanced ultrafiltration methodologies for the resolution of racemic benzoin
Olceroglu, Ayse Hande; Çalık, Pınar; Yılmaz, Levent (Elsevier BV, 2008-09-15)
In the scope of achieving the separation of chiral molecules, enzyme enhanced ultrafiltration (EEUF), a new method based on polymer enhanced ultrafiltration (PEUF), utilizing apoenzymes as ligands, was developed. Benzoin was chosen as the model chiral molecule. Bovine serum albumin (BSA) and apo form of benzaldehyde lyase (BAL) (E.C. 4.1.2.38) were used as chiral ligands in PEUF and EEUF experiments, respectively. In order to bind to the target enantiomer well, the addition of ligand to the benzoin solution...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
P. Z. Çulfaz Emecen, M. Wessling, and R. G. H. Lammertink, “Fouling behavior of microstructured hollow fibers in cross-flow filtrations: Critical flux determination and direct visual observation of particle deposition,”
Journal of Membrane Science
, pp. 210–218, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39744.