Study On Preparation Of Zeolite Via Fly Ash

Dozens of years have past since zeolite was synthesized via fly ash. There is still much work to do in foundation and application due to difference of composition from various places, after combustion under various conditions, though progresses have been got in synthesis methods, characterization and properties measurements.The paper uses fly ash resource from Shan Xi Hua Neng combustion power source as feedstock with Fe content of6.27%percent. The Fe in fly ash was partly removed by magnetic selection method, under the optimized conditions:size is of0.058mm, magnetic strength is about744kA·m-1, the ratio of fly to water is3to1, the calcinations temperature is500℃, time is4. Fe content decreased to be1.82%after the optimal magnetic selection.4A zeolite was prepared using magnetic-selected fly ash via hydrothermal method and characterized by BET, XRD, SEM and FT-IR. Experimental results show that feasible reaction temperature is600℃, mass ratio of fly ash to alkali is1to2, crystal temperature is90℃, crystal time length is24h. Under the experimental conditions,4A-type zeolite with good crystal morphology was obtained. The research result provides ideology and practical reference for the industrial production of4A zeolite in times to come.Static-water absorption is a principal target, which fundamentally reflects properties of zeolite. The research presents water-absorption results of the zeolite made from fly ash:18.6%percent of water at most was adsorbed by the X-type zeolite (n(Si)/n(Al)=2.5)after being vacuumized for1h, and placed in a vacuum drying oven loaded with NaCl water solution, for24h. CO2adsorption amount reaches19.72%on13X-type zeolite at0.4Mpa while CO2adsorption amount on5A-type zeolite attains to be15.15%at0.4Mpa.