摘要
研究了TiO2晶须在光催化深度净化饮用水过程中失活的原因及相应的再生方法.对TiO2薄膜失活前后的AFM、XRD表征,以及对失活前后TiO2晶须酸洗液的ICP分析表明,TiO2晶须失活的主要原因是难溶性碳酸钙在催化剂表面的沉积.由于自来水中钙离子的存在以及有机物光催化降解过程中产生的二氧化碳,生成的难溶性碳酸钙覆盖在催化剂的表面,影响了紫外光的透光率,限制了光生电子和光生空穴的生成,导致催化剂的光催化能力逐渐下降直至失活;失活的催化剂通过1 mol/L的盐酸酸洗4 h后,光催化活性可以恢复到95%左右;多次失活/再生的催化剂的光催化活性保持较好的稳定性.
The reason of deactivation of titania whiskers used for deep purification of drinking water and the corresponding regeneration methods were presented. AFM,XRD and ICP were carried out to characterize the titanium dioxide.The experimental results suggest that the main reason of deactivation of titania whiskers is the deposition of calcium carbonate on the catalyst surface.The surface of titania whiskers is covered by the insoluble carbonates generated from carbon dioxide produced during the degradation of organics and metal ions such as calcium in the tap water,and the activity of the titania whiskers decreases gradually till deactivation.After washing by 1mol/L hydrochloric acid for four hours,the photocatalytic activity of the titania whiskers can achieve 95 percent of that before deactivation.The photocatalytic activity of the titania whiskers which regenerated for many times keeps steady.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2007年第9期2025-2029,共5页
Environmental Science
基金
国家自然科学基金项目(20246002
20236010)
江苏省环保科技发展项目(2005001-2)
中石油技术开发项目(W06-03C-01-03-02)
关键词
TiO2晶须
光催化
饮用水净化
失活
再生
titania whiskers
photocatalyst
purification of drinking water
deactivation
regeneration
