钢渣-粉煤灰水热合成方沸石及其性能表征

Hydrothermal synthesis of analcime from steel slag-fly ash and its performance characterization

本研究以钢渣、粉煤灰为原料,使用氢氧化钠和水玻璃的复配激发剂,先制备出钢渣-粉煤灰基地质聚合物,再通过水热合成的方式成功合成了方沸石。重点考察了不同摩尔比n(SiO_2)/n(Al_2O_3)和不同钢渣粉煤灰用量对合成方沸石的影响,并采用XRF、XRD、SEM、TEM以及TG-DSC等手段对原料、中间产物以及最终产品进行了分析表征,并利用BET研究了产品的比表面积及孔结构的变化。结果表明,当钢渣和粉煤灰用量为4∶6,摩尔比n(SiO_2)/n(Al_2O_3)为4.2,水热温度控制在150℃~180℃时,能够合成物相较纯、晶相较好并且具有一定热稳定性的方沸石。相比于传统的以粉煤灰作为原料的合成方沸石方案,创新性地掺入钢渣,为钢渣的资源化利用提供了新途径。

In this study,geopolymers were prepared by steel slag,fly ash,and alkali activitor of sodium hydroxide and sodium silicate solution. Then the analcime was synthesized by hydrothermal methods. It is investigated the effects of different molar ratios of n( SiO_2)/n( Al_2O_3) and steel slag/fly ash contents on the synthesis of analcime. The raw materials,intermediate products and final products were characterized by XRF,XRD,SEM,TEM and TG-DSC. The specific surface area and pore structure of the products were also investigated by BET. The results show that the analcime with relatively pure crystalline phase can be synthesized when the amount of steel slag and fly ash is 4∶ 6,the n( SiO_2)/n( Al_2O_3) molar ratio is 4. 2 and the hydrothermal temperature is between 150 ℃ and 180 ℃. Meanwhile,the analcime products exhibited certain thermal stability. Compared with the traditional synthesis of analcime with fly ash,the addition of steel slag providing a new approach for the resource utilization of steel slag.