MINERAL COMPOSITION AND PROPERTIES OF MODIFIED FLYASH

Fly ash is one of the surplus products created in the combustion process. In industry, fly ash usually refers to ash produced during combustion of coal and is usually taken from the chimneys of thermal power plants. Currently, in Vietnam burning coal to generate electric energy are necessary. Fly ash discharged occupied huge area and polluting the environment. Thus the study of fly ash recycling reasonable to reuse waste enormous resources will have economic and environmental significance. Fly ash of Pha Lai Thermal Power Plant (FA-PL) was modified in strong alkaline conditions (NaOH 3N), stirred at a temperature of 100 0 C for 1h obtained with a mixture of minerals including: quartz accounts for 24 - 26%, accounting for 22-24% mullite, zeolite Na-P2 accounted for 24-26%, other types of small mineral occupies 10-16%, the rest is amorphous accounted for 8-20%. This modified product has cation exchange capacity (CEC) of 170 cmol/kg, it is 5.6 times larger than the original fly ash (30 cmol/kg). With high CEC values open up new vistas in using modified fly ash material to handle with polluted soil and water environment.