Hsin Shao

Effects of activated carbon characteristics on the electrosorption capacity of titanium dioxide/activated carbon composite electrode materials prepared by a microwave-assisted ionothermal synthesis method.

Titanium dioxide (TiO2)/ activated carbon (AC) composite materials, as capacitive deionization electrodes, were prepared by a two-step microwave-assisted ionothermal synthesis method. The electrosorption capacity of the composite electrodes was studied and the effects of AC characteristics were explored. These effects were investigated by multiple analytical techniques, including X-ray photoelectron spectroscopy, thermogravimetry analysis and electrochemical impedance spectroscopy, etc. The experimental results indicated that the electrosorption capacity of the TiO2/AC composite electrode is dependent on the characteristics of AC including the pore structure and the surface property. An enhancement in electrosorption capacity was observed for the TiO2/AC composite electrode prepared from the AC with higher mesopore content and less hydrophilic surface. This enhancement is due to the deposition of anatase TiO2 with suitable amount of Ti-OH. On the other hand, a decline in electrosorption capacity was observed for the TiO2/AC composite electrode prepared from the AC with higher micropore content and highly hydrophilic surface. High content of hydrogen bond complex formed between the functional group on hydrophilic surface with H2O, which will slow down the TiO2 precursor-H2O reaction. In such situation, the effect of TiO2 becomes unfavorable as the loading amount of TiO2 is less and the micropore can also be blocked.

The Usage of Non‐woven Fabric Material as Separation Media in Submerged Membrane Photocatalytic Reactor for Degradation of Organic Pollutants in Water

Abstract Photodegradation tests with continuous mode were carried out in a photocatalytic reactor containing a submerged flat sheet non‐woven fabric membrane, which was able to retain the photocatalyst. The non‐woven fabric membrane was made of polypropylene with a pore size of 2 µm. In this study, three operational parameters were investigated: light intensity, feed concentration, and feed flow rate. Experimental results showed no significant variation of permeate flux and TMP (transmembrane pressure) during the experimental period. The SS (suspended solid) of the permeate was non‐detectable. These behaviors were due to the formation of a dynamic porous cake layer on the non‐woven fabric membrane surface in our experimental condition. We also found that it was important to control the operation parameter mentioned above as to exactly when we wanted to maintain the steady pollutant concentration in the permeate at very low value.