Published 2002 | Version v1
Journal article

Synthetic crystalline calcium silicate hydrate (I): cation exchange and caesium selectivity

  • 1. Chemistry Department, Faculty of Science, Suez Canal University, Ismailia (Egypt)

Description

Solid crystalline calcium silicate hydrate (I) synthesized from equimolar amounts of Ca and Si under hydrothermal conditions at 120 oC shows cation exchange properties towards divalent metal cations such as Ni, Cu, Cd, or Hg. It also exhibits caesium selectivity in the presence of Na+. The exchange capacity and selectivity of the solid can be increased by 10 and 28 %, respectively, upon substitution of 0.01 mol of the Ca2+ in its structure by Na+. The ability of metal cation uptake by the solid was found to obey the order Ni2+ > Hg2+ > Cu2+ > Cd2+. The different affinities of calcium silicate hydrate (I) towards these ions can be used for their separation from solutions and also in nuclear waste treatment. The mechanism of the exchange reaction is discussed. (author)

Additional details

Publishing Information

Journal Title
Monatshefte fuer Chemie
Journal Volume
133
Series
Issue 3
Journal Page Range
p. 333-343
ISSN
0026-9247
CODEN
MOCHAP