Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Science 6 January 1967:
Vol. 155. no. 3758, pp. 71 - 72
DOI: 10.1126/science.155.3758.71
Prev | Table of Contents | Next

Articles

Tactoid Formation in Montmorillionite: Effect on Ion Exchange Kinetics

Amos Banin 1

1 Department of Soil Science, Hebrew University, Rehovot, Israel

Exchange between calcium from montmorillonite and hydrogen from resin is much slower than exchange between sodium from montmorillonite and hydrogen from resin. Film kinetics are prevailing in both cases, but the location of the rate-determining step is shifted from the Nernst films of the resin particles in the sodium-hydrogen exchange to the Nernst films of the clay particles in the calcium-hydrogen exchange. The increased particle size of the montmorillonite in the calcium state, caused by tactoid formation, appears to be the main reason for the shift.

To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)