Published Online: 30 August 2013
Page Count: 11
Research Scholar, Civil Engineering Dept., Indian Institute of Technology, Bombay, Powai,
Singh, D. N.
Professor, Civil Engineering Dept., Indian Institute of Technology, Bombay, Powai,
(Received 19 April 2013; accepted 16 July 2013)
Several researchers have established the fusion of fly ash–NaOH mixtures at 450°C to 900°C. The fly ash gets partially converted to zeolite X when the fused ash is further treated in a hydrothermal system. However, such a solid residue (the end product) exhibits a low cation-exchange capacity. A culprit of such a deficiency in zeolite is improper contact between the NaOH and the fly ash particles during their fusion. To enhance the degree of fusion, in the present study we attempted to demonstrate a three-step fusion technique that does not favor any further treatment in a hydrothermal system. Observed changes in the characteristics (cation exchange capacity, pore volume, pore area, mineralogy, and thermal stability) of the end product of three-step fusion corresponding to an NaOH/fly ash ratio equal to 1.0 proves the suitability of this fusion technique for the synthesis of a better grade of zeolite X (viz., Na-X and Na-Y).
Paper ID: MPC20130016