Treatment of Coal Fly Ash for Cation Exchange Capacity Improvement

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Suwan Chaiyasith
Chutima Septhum

Abstract

Previously, utilizations of coal fly ash as an absorbent for the removal of heavy metals from wastewater have not been successful because of its low cation exchange capacity (CEC). Many attempts have been made to improve the properties of fly ash. In this study we refluxed coal fly ash with 1.0 M NaOH for 24 hrs. As a result, the CEC of the treated fly ash increased by a factor of 24 to almost 200 meq/100 g compared to untreated fly ash. Porosity and crystallization of the treated fly ash also increased and it was converted into zeolite Na-P and sodalite octahydrate. The concentration of Na2O in treated fly ash was 6 times higher than in untreated fly ash.


Keywords: adsorbent, CEC, trated fly ash, heavy metals, zeolite


Corresponding author: E-mail:  kcsuwan@kmitl.ac.th

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Original Research Articles

References

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