Research on Extracting Silicon and Iron Oxide from the Waste Ash of Mongolian Fourth Thermal Power Plant

In this research, we extracted silicon and iron oxides from the waste ash of the Mongolian fourth thermal power plant by a precipitation method. The samples were analyzed using XRD, XRF, BET, and SEM, and the following conclusions were reached. From the quantitative analysis of the chemical composition, the bottom and fly ash of the Mongolian fourth thermal power plant belong to the acid ash. The results of instrumental analysis of iron oxide obtained from the waste ash (XRF, XRD, BET, SEM), the ratio of ash to hydrochloric acid is 1:6, the hydrochloric acid concentration is 20%, the reaction temperature is 75°C, stirring speed is 250 rpm. The properties of the prepared iron oxide are the best and yield 20%, purity of 41.587%, average pore diameter of 7.5379 nm, and specific surface area of 38.87 m2 /g.The results of instrumental analysis of silicon dioxide obtained from the waste ash (XRF, XRD, BET, SEM) show the ratio of ash to hydrochloric acid is 1:6, the hydrochloric acid concentration is 20%, the reaction temperature is 75°C, stirring speed is 200 rpm. The yield is about 75%, the purity is 99.999%, the average pore diameter is 27.96 nm, and the specific surface area is 353.59 m2 /g.