The adsorption of NH₄^+ and Zn^(2+) by four Korean zeolites, the major species of which are clinoptilolite, clinoptilolite with mordenite, mordenite with clinoptiIolite, and mordenite was measured in different concentrations of solutions of NH₄^+ and Zn^(2+), and their mixtures.
The adsorption of NH₄^+ was greate, than that Zn^(2+) far all samples at the concentrations of the added solutions from 1 to 7 × 10^(-3)N and this difference was greater at the higher concentrations. Also, Zn^(2+) adsorption by samples was decreased by the presence of NH₄^+, but that of NH₄^+ by the presence of Zn^(2+) was not. The extent of NH₄^+ selectivity among samples was increased in order of clinoptilolite with mordenite $lt;clinoptilolite $lt;mordenite with clinoplolite $lt;mordenite. Cumulative amounts of NH₄^+ adsorbed by six successive equilibrations with range from 43.7 to 50.4 me/100g, whereas those amounts of Zn^(2+) were in the range from 6.6 to 17.0 me/100g.
It was suggested from these results that mordenite and clinoptilolite, particularly the former, can be used for removal of NH₄^+ from municipal wastewater and those zeolites treated with wastewater can be applied to agricultural land.
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