Effects of Particle Size and Temperature on the Ammonium Ion Exchange by Natural Zeolite

천연제올라이트의 암모늄이온교환에 미치는 입자 크기 및 온도영향에 관한 연구

Ammonium ion is notorious for the adverse effects upon many of the important uses of water such as toxcity to fish, corrosion of metals and concrete, and concern over man's consumption. A clinoptilolite, which is a naturally occurring zeolite selective for ammonium ion exchange, has been used. Batch isotherm experiments were conducted for measuring ammonium ion exchange capacity. The ion exchange capacity was well described either by the Langmuir equation or by the Freundlich equation. As the particle size of the clinoptilolite decreased, exchange capacity was increased. The smaller particle size enhaced the exchange of ammonium ion due to the greater surface area and decreased diffusion to the exchange sites within the zeolite. Ammonium ion exchange capacity tended to decrease when the temperature increased from $20^{\circ}C$ to $35^{\circ}C$, and the temperature correction factor was found to be 0.98 in the Langmuir equation.