Preparation of <scp> <scp>Na</scp> </scp> ‐ <scp> <scp>P</scp> </scp> 1‐Type Zeolite and its Composite Material with Nanosized Magnetite

Abstract

The Na ‐ P 1‐type zeolite having a high cation‐exchange capacity ( CEC ) was obtained using the waste coal fly ash from thermal power stations and a 2 M NaOH solution at 100°C. The Na ‐ P 1‐type zeolite was formed with the reaction time of 6 h at 100°C, and its CEC value increased with an increase in the reaction time. The addition of a suitable amount of NaAlO 2 to the fly ash was also effective for improving the CEC value. A new composite material consisting of the Na ‐ P 1‐type zeolite and magnetite was synthesized from the fly ash and iron chlorides because the magnetic collection was possible using this composite material after radioactive Cs + ion adsorption. The existence of nanosized magnetites in the polycrystalline zeolite (several micrometers) was confirmed by TEM observations. The CEC and magnetic property of these composite materials were characterized.