铝改性秸秆生物质炭去除水体中的大肠杆菌

Removal of Escherichia coli from Water Using Al(Ⅲ)-modified Crop Straw Biochars

用一次平衡实验和柱淋溶实验研究了秸秆生物质炭和铝改性秸秆生物质炭对水中大肠杆菌的吸附量和去除率。结果表明,未改性秸秆生物质炭对大肠杆菌的吸附量很低,铝改性秸秆生物质炭对大肠杆菌有很高的吸附容量和去除率,0.6 mol/L Al(Ⅲ)改性生物质炭对大肠杆菌的去除效果优于0.3 mol/L Al(Ⅲ)改性生物质炭。当大肠杆菌浓度低于0.63 mg/ml时,铝改性大豆秸秆炭对大肠杆菌的去除率达100%,铝改性花生秸秆炭和铝改性稻草炭对大肠杆菌的去除率在96%和90%以上。0.5 mg/ml的大肠杆菌悬液通过装有2 g铝改性稻草炭的淋溶柱,每次收集10 ml淋出液,共收集152次,大部分淋出液中大肠杆菌浓度小于0.02 mg/ml,大肠杆菌去除率在95%以上。因此,铝改性生物质炭可用于水体中大肠杆菌的去除。

Batch and leaching experiments were conducted to investigate the adsorption and removal of Escherichia Coli （E. coli） from water by crop straw biochars and Al（Ⅲ）-modified biochars. Results indicated that the amount of E. coli adsorbed by non-modified crop straw biochars was very low, while Al（Ⅲ）-modified crop straw biochars showed great adsorption capacity and high removal efficiency for E. coli. The adsorption capacity of the biochars modified by 0.6 mol/L Al（Ⅲ） was greater than that of the biochars modified by 0.3 mol/L Al（Ⅲ）. When the concentration of E. coli was less than 0.63 mg/ml, the removal percentage ofE. coli was 100% by Al（Ⅲ）-modified soybean straw biochar and more than 96% and 90% by Al（Ⅲ）-modified peanut straw bioachar and Al（Ⅲ）-modified rice straw biochar, respectively. In leaching experiment, when the suspension of 0.63 mg/ml E. coli passed through the leaching column containing 2 g Al（Ⅲ）-modified rice straw biochar, 152 leachates were continuously collected with each leachate of 10 ml. The concentration of E. coli in most leachates was less than 0.02 mg/ml and the removal percentage of E. coli from the suspension was above 95%. Therefore, Al（Ⅲ）-modified crop straw biochars can be used to remove E. coli from water efficiently.