4种填料对氨氮的吸附效果

Adsorption effect of ammonia by four fillings

氮是引发湖泊富营养化的重要元素之一,湖泊外源和内源氮的去除对湖泊富营养化的控制非常关键,其中填料对氨氮的去除是湖泊外源控制的重要途径.研究了4种填料(天然沸石、陶粒、蛭石和土壤)对氨氮的吸附行为、填料去除氨氮的主要途径以及溶液中pH值和温度对氨氮去除率的影响.结果表明沸石对氨氮的吸附效果明显,蛭石次之,土壤与陶粒效果较差.沸石去除氨氮的途径以离子交换作用为主,物理吸附作用很小;陶粒、土壤和蛭石3种填料的离子交换作用和物理吸附作用的效果相当.4种填料的吸附量在温度为15-35℃内均随温度的升高而减小,在pH值为3-9范围内随pH值升高而增大,振荡6h均达到吸附平衡.

Nitrogen is one kind of important elements related to eutrophication of lakes. The removal of exterior pollution source and interior pollution source is significant for eutrophication control of lakes. Ammonia removal by fillings is an important ways for the control of exterior pollution source of lakes. The ammonia adsorption behavior of four kinds of fillings, such as savageness zeolite, haydite, vermiculite and soil were investigated. The main way of ammonia removal by fillings, the effects of solution pH and temperature on removal rate of ammonia were observed. The results indicated that there were significant differences between zeolite and other fillings, and the sorption efficiency in the order were zeolite, vermiculi, soil and haydite. The ion exchange function is the main way of removing ammonia by zeolite, zeolite has the worst sorption ability, whereas other three fillings have almost the same sorption and ion exchange capacities. In addition, adsorption capacities of these four fillings decreased as temperature increased between 15-35℃; as the pH values increased at the range of 3-9 the adsorption capacities of these four fillings increase too. All adsorption experiments reached equilibrium within six hours.