Membrane Fouling Characterization by Confocal Scanning Laser Microscop Unitat d'Enologia del CeRTA. Departament d’Enginyeria Química, ETSEQ, URV Tarragona, Spain student: Maria Zator supervisor: Carme Guell

3.from membrane separation to CSLM analysis... 2.Membrane fouling characterisation... 6.Future plans... a. Importance... Outlines 1.Membrane fouling... Membrane Fouling Characterization by Confocal Scanning Laser Microscopy b. Some definitions... 5.Conclusions... 4.Results...

1a. What is important... Fouling characterisation - generally Fouling characterisation – present study fundamental mechanisms & processes involved not fully understood novel, non-invasive, in-situ quantification of physico-chemical processes key to breakthroughs in the understanding of fouling phenomena Confocal Scanning Laser Microscope appropriate strategy for membrane fouling characterization

1b....membrane fouling... Flux as a function of time. The biggest problem associated with the application of the separation processes for membranes is FOULING What is the problem...? What is fouling...? The fouling is manifested as a decrease of the permeate flux during the time of filtration Why fouling is a problem...? The (ir)reversible deposition of retained particles, colloids, emulsions, suspensions, macromolecules, salts etc. on or in the membrane. INTERNAL FOULING EXTERNAL FOULING

2. Membrane fouling characterisation In situ methods Monitoring techniques for concentration polarization Visualization of the adsorption/deposition of particles on the surface of membranes Monitoring techniques for pore blockage Monitoring techniques for cake layer formation Indirect methods Analysis of the chemical composition of the permeate and retentate Evaluation of permeate flux and total resistance versus time Chemical and physical analysis of membranes (microscopic techniques: SEM and AFM) New Method CSLM Confocal Scanning Laser Microscope excellent technique to visualise protein adsorption to porous particles and membranes

3. From membrane separation to CSLM analysis COMPUTER 5 %5 % BALANCE STIRRERPUMP DEAD – END MODUL moviol cover glass slide CSLM Sample preparationFiltration plant Data gathering

4. Results IMAGE ANALYSIS Fouling morphology Volumetric 3D reconstruction CSLM : 6,5% +/- 0,5 SEM : 7,1 % +/- 0,6 Determination of surface porosity Orthogonal view of the 3D reconstruction Location and identification of the adsorbed/depos ited proteins CSLM BSA- fluorescein and OVA- TexasRed conjugate. ZY ZX XY OVA- TexasRed conjugate. CSLM BSA- fluorescein and OVA- TexasRed conjugate. BSA- fluorescein conjugate. Data about pore surface in which protein was detected

5. Conclusions CSLM can be used to characterize membrane several agents in a mixture that cause fouling can be visualised several agents in a mixture that cause fouling can be visualised information about the presence of proteins on the surface and inside the membrane can be obtained information about the presence of proteins on the surface and inside the membrane can be obtained prevailing mechanism during fouling and the major fouling agent can be identified prevailing mechanism during fouling and the major fouling agent can be identified the formation of cake on the top of the membrane and/or the pore constriction caused by deposition or adsorption of foulant can be visualised the formation of cake on the top of the membrane and/or the pore constriction caused by deposition or adsorption of foulant can be visualised ZYZY ZXZX XYXY

6.... and further steps... FUTURE PLANS Quantitative information about membrane fouling Characterisation of reversible/irreversible membrane fouling filtration module modifications to carry out on-line experiments Set up membrane cleaning procedure

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