Title : Surface functionalized ceramic membrane using super hydrophilic catalysis to enhance of oil in water separation
Abstract:
Coating surfaces with thin or thick films of zwitterionic material is an effective method to reduce or eliminate nonspecific adsorption to the solid/ liquid interface. The coating of the membranes was done in place i.e., while the membranes were fixed in the membrane housing connected to the filtration rig. 1 M cysteic acid solution was prepared using distilled water in the feed tank and preheated to 65oC. The filtration rig was then run with the permeate side open for 12 hours at a temperature of 85oC. Conductivity measurements from the permeate side were taken and when four approximately equal Two alpha-alumina microfiltration membranes operated in crossflow mode were tested with feed water containing 1000 ppm mineral oil. The ceramic membranes have a mean pore size of 0.2 µm and are multichannel with tubular configuration.
The use of zwitterions to protect surfaces is expected to raise, for example would be protecting membranes from fouling by particles and organics. Because zwitterion interactions are reduced with exposure to aqueous NaCl, they are ideally suited for physiological or marine conditions and applications. Stable oil-in-water emulsion was treated using surface modified ceramic microfiltration membranes in crossflow mode. The ceramic membranes were surface treated with cysteic acid (HO3SCH2CH(NH2)CO2H) in order to improve their performance evaluated by flux monitoring and oil rejection efficiency. The cysteic acid is not intended to create a separation layer on the membrane surface but enhanced the hydrophilic feature of the membrane. The ceramic membranes showed high hydrophilicity by attaining a steady sustained flux in a short time indicating reduced membrane fouling. The flux was monitored under constant pressure operation and results showed that the membrane performance was improved significantly. The membrane efficiency was found to be greater than 99% with permeate quality of less 5mg/L oil concentration. The cysteic acid coating when compared to other coating materials like nano-TiO2 and nano-ZrO2, exhibited a superior capability in improving membrane performance.
