Gerrity Daniel, Ryu Hodon, Crittenden John, Abbaszadegan Morteza
National Science Foundation Water Quality Center, Department of Civil and Environmental Engineering, Arizona State University, Tempe, Arizona 85287-5306, USA.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2008 Sep;43(11):1261-70. doi: 10.1080/10934520802177813.
The carcinogenic potential of chlorine disinfection by-products and recent changes in water quality regulations have led to a greater emphasis on alternative disinfection mechanisms. In this study, the efficacy of bench-scale and pilot-scale titanium dioxide (TiO(2)) photocatalytic disinfection was explored using four bacteriophages (MS2, PRD1, phi-X174, and fr). The optimized bench-scale experiments indicated that 1 mg/L of Degussa P25 TiO(2) irradiated by low-pressure ultraviolet (UV) light reduced the dose requirements for viral inactivation in comparison to UV light alone. The highest UV dose reductions for 4-log inactivation of PRD1, MS2, phi-X174, and fr were 19%, 15%, 6%, and 0%, respectively. Bench-scale photocatalysis was inhibited by limited adsorption of the viruses onto the TiO(2) nanoparticles, as indicated by the poor results for high TiO(2) concentrations. Subsequently, pilot-scale experiments were completed using the Photo-Cat Lab from Purifics. The annular reactor configuration and increased viral adsorption dramatically improved photocatalytic inactivation for samples with high TiO(2) concentrations. Using the Photo-Cat Lab, 2-log inactivation of the bacteriophages was achieved with 400 mg/L of Degussa P25 TiO(2) and a UV dose of approximately 34 mJ/cm(2) (energy consumption of 0.33 kWh/m(3))-a 700-fold decrease in energy use compared to bench-scale photocatalysis.
氯消毒副产物的致癌潜力以及水质法规的最新变化，使得人们更加重视替代消毒机制。在本研究中，使用四种噬菌体（MS2、PRD1、phi-X174和fr）探索了实验室规模和中试规模的二氧化钛（TiO₂）光催化消毒的效果。优化后的实验室规模实验表明，与单独使用紫外光相比，1 mg/L的德固赛P25 TiO₂在低压紫外光照射下降低了病毒灭活所需的剂量。对于PRD1、MS2、phi-X174和fr的4对数级灭活，最高的紫外剂量降低分别为19%、15%、6%和0%。实验室规模的光催化受到病毒在TiO₂纳米颗粒上有限吸附的抑制，高TiO₂浓度下效果不佳就表明了这一点。随后，使用Purifics公司的Photo-Cat Lab完成了中试规模实验。环形反应器配置和增加的病毒吸附显著提高了高TiO₂浓度样品的光催化灭活效果。使用Photo-Cat Lab，400 mg/L的德固赛P25 TiO₂和大约34 mJ/cm²的紫外剂量（能耗为0.33 kWh/m³）实现了噬菌体2对数级的灭活——与实验室规模的光催化相比，能源使用减少了700倍。
