化学改性大蒜茎叶对含Pb(Ⅱ)废水吸附的研究

Research on the adsorption capacity of chemically modified garlic stems & leaves for Pb(Ⅱ)-containing wastewater

采用大蒜茎叶为原料,经异丙醇、氢氧化钠和柠檬酸处理,制备出改性吸附剂并用于吸附Pb(Ⅱ)的实验。考察了溶液酸度、吸附平衡时间、最大吸附量、固液比等因素对金属离子吸附平衡的影响。结果表明:改性剂柠檬酸最佳浓度为0.6 mol/L,最佳的制备温度是80℃。经柠檬酸改性的大蒜茎叶吸附剂对Pb2+的最佳吸附p H=5,在120 min内建立了反应平衡,对Pb2+的最大吸附量是119.62 mg/g。

Modified adsorbent has b een prepared with garlic stems ＆ leaves as raw materials ,which were treated with C3H8O,NaOH,and C6H6O7·H2O,and has been applied to the adsorption for Pb （Ⅱ）. The influences of the factors,such as initial pH,adsorption equilibrium time,maximum adsorption capacity,solid/liquid ratio,etc. on the adsorption equilibrium of metal ions are investigated. The results show that the optimal concentration of modifier cit-ric acid is 0.6 mol/L,and optimal preparation temperature 80℃. The optimal conditions for adsorbing Pb2＋by the citric acid-modified garlic stems ＆ leaves adsorbent are as follows：pH is 5 and adsorption time within 120 min. Thus,the reaction equilibrium can be established and the maximum adsorbing capacity for Pb2＋is 119.62 mg/g.