Ammonium–Potassium–Calcium Exchange on Vermiculite and Hydroxy-aluminum Vermiculite
- V. P. Evangelou * and
- J. Lumbanraja
Binary and ternary cation-exchange reactions involving NH+ 4, K+, and Ca2+ on vermiculite and hydroxy-Al interlayered vermiculite (HIV) were investigated. In the case of vermiculite, NH4-Ca exchange was nearly indistinguishable from the nonpreference isotherm while HIV exhibited preference for NH+ 4 The presence of K+ had significant suppressing impact on the apparent NH+ 4 selectivity in NH4-Ca exchange in HIV most likely because of retardation of Ca2+ diffusion in the interlayer. For vermiculite, the presence of K+ in the NH4-Ca system induced apparent high affinity sites for NH+ 4 most likely because of interlayer collapse. The overall study demonstrated that cation-exchange selectivity coefficients in vermiculite and HIV are dependent on number and type of cations present.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2002.