13X分子筛去除水中重金属离子的研究

以人工合成的13X型分子筛为吸附剂,研究了水中Pb2 、Cd2 和Cu2 在分子筛上的吸附行为,讨论了Pb2 、Cd2 和Cu2 共存条件下的竞争吸附,并考察了水中存在的Na 、Mg2 、Ca2 等离子对分子筛吸附去除重金属的影响.实验结果表明,13X分子筛对Pb2 、Cd2 和Cu2 3种离子的吸附符合Langmuir模型,最大吸附量分别为2.47mmol/L、2.0mmol/L和1.78mmol/L.在竞争吸附条件下,13X分子筛对3种重金属离子的选择性依次为pb2 ＞Cd2 ＞Cu2 .水中存在的Na 、Mg2 、Ca2 等对分子筛吸附重金属效率有一定的影响,其中Ca2 对Cu2 在分子筛上的去除影响最为显著.

STUDY ON THE REMOVAL OF AQUEOUS HEAVY METAL CATIONS BY 13X ZEOLITE

In this study,the adsorption and competitive adsorption of Pb2 ,Cd2 and Cu2 onto 13X zeolite was studied.The influence of aqueous Na ,Mg2 and Ca2 cations on the removal efficiency of the heavy metals was also investigated.The results showed that the adsorption of the heavy metals onto the zeolite was well described by Langmuir adsorption model and the maximum adsorption amounts of Pb2 ,Cd2 and Cu2 onto 13X zeolite were found to be 2.47mmol/L,2.0mmol/L,1.78mmol/L,respectively.The competitive adsorption results revealed that the adsorption selectivity of the zeolite for the metal cations decreased as Pb2 >Cd2 >Cu2 .The removal efficiencies of the metal cations were related to other ions.In particular,the presence of Ca2 led to a markedly decreased adsorption capacity of the zeolite for Cu2 .