Zeta Potential and Mobility of Particles

A Coulter Delsa 440 Zeta Sizer was used to measure the particle mobility from which zeta potential was calculated. The method is based on the movement of charged particles in between two electrodes, imposing current or voltage. The samples were equilibrated for at least 12 hours at a defined solution chemistt) prior to analysis which was carried out at 25 C. 

2 Particle Size and Structure Analysis/Fractal Dimension (Malvern) 

Particle size and aggregate fractal dimension were measured with a Malvern Instruments Mastersizer/E. A 100 mm lens was used to measure particle sizes between 200 nm and 110 im (the 45 mm lens allowed particle analysis from 50 nm to 80 pm). Measurements were taken immediately after filling the cell to avoid settling effects, and no stirring was applied. 

Since the aggregation process is a function of time, samples of the feed suspension were taken prior to the filtration experiments and immediately analysed with the Malvern Mastersizer. Size distribution information was directly available from the instrument output. 

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