改性蚯蚓粪对重金属Cu^(2+)的吸附性能研究

研究了蚯蚓粪吸附剂对溶液中Cu^(2+)的吸附性能,实验结果表明,蚯蚓粪吸附剂具有较强的吸附能力,改性前后对低浓度Cu^(2+)仍具有较强的去除效率;溶液pH=5时具有最大吸附率,前30 min内吸附速率极快,至120 min基本达到最大吸附量;吸附温度在20~40℃之间以物理表面吸附为主,40~50℃之间化学吸附能力增强;单位吸附剂对溶液Cu^(2+)的平衡吸附量与Cu^(2+)的初始浓度的关系符合Langmuir吸附等温线方程。在初始Cu^(2+)浓度为0.002 mol/L,温度50℃,时间120 min时,平衡吸附量分别为3.99 mg/g和2.28 mg/g。

This paper is aimed to study on the performance of vermicompost adsorbing copper ions from aqueous solution. Experimental results show that vermicompost adsorbent has strong adsorption capacity. Activated and non-activated vermin-compost have a strong copper ion removal efficiency for the low-concentration solution; and the optimum range of pH value for absorbing Cu2＋ with the absorber is 5, a very fast rate of adsorption in 30 min- utes, after 120 minutes, the adsorption reached balance state basically and then the adsorption amount did not change along with the extending of time; based on the physical adsorption between 20℃ to 40℃, and then the chemical adsorption strengthen between 40℃ to 50℃. The relationship between equilibrium adsorption capacity and initial concentration of copper ions on unit adsorbent is in accordance with Langmuir adsorption isotherm e- quation. Under the conditions of Cu2＋is 0.002 tool/L, 50℃ and adsorption time is 120 minutes, the equilibrium ad- sorption amount were 3.99 mg/g and 2.28 mg/g.