摘要
对高岭土悬浮水溶液在光照过程中产生的羟基自由基(.OH)进行了测定.在pH2.0,苯浓度为7.0mmol·l-1的条件下,经过250W金属卤素灯(λ≥365nm)光照5h,高岭土浓度为20.0g·l-1的悬浮液中,.OH的产生量为21.6μmol·l-1.在pH2.0—10.0范围内,.OH产生量随pH值的降低而增加.高岭土浓度在0—20.0g·l-1的范围内,.OH产生量随高岭土浓度的升高而增加,高岭土浓度增加到25.0g·l-1时,.OH产生量反而减少.高岭土中的铁是.OH产生的重要因素.
By using benzene as scavenger to produce phenol, hydroxyl radicals （ ·OH）produced by illuminating kaolinite suspension was determined with HPLC. In the suspension containing 20. 0g·l^-1 kaolinite and 7. 0mmol·l^-1 benzene at pH 2. 0, 21.6μmol·l^-1·OH produced after irradiation by 250W metal halide lamp （λ≥365nm） for 5h. Low pH value benefited the formation of hydroxyl radicals in the pH range of 2. 0-10. 0. The ·OH concentration increased with increasing the concentration of clays in aqueous solutions in the range of 0-20. 0g·l^-1, higher concentration above 25.0g·l^-1 clays inhibited the ·OH production. Iron in the clays is believed to be one of the important factors determining ·OH formation.
出处
《环境化学》
CAS
CSCD
北大核心
2007年第5期651-653,共3页
Environmental Chemistry
基金
国家自然科学基金资助项目(No.40503016)
关键词
羟基自由基
高岭土
光化学反应
hydroxyl radicals, kaolinite, photochemical reaction.
