中文摘要：

实验研究了在大气压力和室温条件下,利用介质阻挡放电（DBD）等离子体技术结合二氧化钛/活性碳纤维催化剂（Ti O2/ACFs）去除水溶液中的咖啡因。采用溶胶-凝胶法制备得到了Ti O2/ACFs复合催化剂,扫描电镜（SEM）表征显示,二氧化钛在活性碳纤维表面均匀分布。研究表明,当咖啡因的初始浓度为10 mg L-1时,相比较与单独DBD等离子体系,在输入功率40-90 W的范围内,复合催化剂的加入使咖啡因的的去除率提高了12-34%,能量效率提高0.06-0.11 g·k W-1·h-1,矿化率提高7-14%。自由基淬灭实验证明氧气和羟基自由基在咖啡因的降解过程中起到主要作用。产物分析表明咖啡因在等离子体协同Ti O2/活性炭纤维复合体系下的降解途径主要为嘌呤环上的羟基化和开环反应。

英文摘要：

The removal of caffeine in aqueous solution by dielectric barrier discharge （DBD） plasma combined with titanium dioxide/activated carbon fibers （TiO2/ACFs） was investigated at atmospheric pressure and room temperature. The TiOJACFs was prepared by sol-gel method and characterized by SEM. The results indicated that TiO2 was crystallized on the surface of ACFs. The removal efficiency of caffeine was improved 12-34% by putting the TiO2/ACFs catalysts compared with sole DBD system in the of input power of 40-90 W with caffeine initial concentration of 10 mg L-1. The energy efficiency was also increased 0.06-0.11 g-kW- 1 ＂h-l. Meanwhile, the mineralization efficiency of TCC was improved by 7-14 % by combining the TiO2/ACFs catalysts in DBD plasma. Oxygen and hydroxyl radical （＇OH） played a more important role during the treatment process. The major degradation pathway of caffeine was the open-ring reaction and hydroxylation in the pyrimidine ring of caffeine.