The alkali treatment of zeolite molecular sieve and its adsorptive performance toward Pb 2+ ion from aqueous solution were investigated .The results showed that alkali solution treatment could enhance adsorb Pb 2+from aqueous solution effectively .Zeolite treated with 0.50 mol∕L NaOH solution exhibits the highest adsorption capacity .Adsorption kinetics and isotherm of Pb 2+ uptake using alkali modified zeolite molecular could be satisfactorily described with pseudo second-order kinetics model and Langmuir model , respectively .The maximum adsorption capacity calculated by Langmuir model at 30 ℃was 54.64 mg∕g, about 0.60 times higher than the original material .When the adsorbent dosage was greater than 1.0 g∕L with 20 mg∕L Pb2+initial concentration , the adsorption removal efficiency was higher than 98 .5%.Common cations could affect the adsorption process , and the effect sequence was Cu 2+>Na+≈K+>Mg2+.Besides, IR, BET and XRD analysis were employed to characterize the materials, and it was found that the increase of average pore diameter and the decrease of Si ∕Al ratio were the main reasons of the increase of adsorption capacity after the alkali treatment .%采用NaOH溶液对市售ZSM－5沸石分子筛进行改性，研究发现，碱改性分子筛吸附去除水中Pb2＋的性能得到提高，经0．50 mol∕L NaOH改性效果最好。对改性前后分子筛的吸附动力学及等温线开展研究，结果表明，改性前后分子筛吸附过程均符合假二阶动力学模型，吸附等温线均符合Langmuir吸附等温式，30℃下碱改性分子筛最大吸附容量为54．64 mg∕g，是未改性分子筛的1．60倍。对于初始浓度为20 mg∕L的Pb2＋，当碱改性分子筛投加量大于1．0 g∕L时，吸附去除率大于98．5％。考察水中常见阳离子Cu2＋、K＋、Na＋、Mg2＋的干扰作用，各离子影响顺序为Cu2＋＞Na＋≈K＋＞Mg2＋。此外，采用红外光谱、BET和XRD手段对改性前后分子筛进行表征，发现分子筛孔径增大，硅铝比降低是改性分子筛吸附性能提高的主要原因。
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