Conversion from iron slags to high function zeolites and their applications

最近，人们希望对铁渣进行更多的再利用，以发展循环利用工艺。本研究开发了铁渣转化为功能更高的高性能铝硅酸盐（FAU沸石、X、Y、氟云母）的工艺。以水淬高炉炉渣为原料，经浓盐酸预处理，制得硅胶为原料。用稀盐酸预处理慢冷高炉炉渣，制备了控制硅铝比的铝硅凝胶。采用微波加热法快速进行酸处理。用NaAlO^2和NaOH溶液混合水热合成了Si/Al = 1.3 ~ 9.5的X型和Y型FAU沸石，产率令人满意。这些沸石X和Y的产物具有较大的Langumuir吸附比表面积，分别为约730 m^2 g和约875 m^2 g。与直接加热法相比，微波热液处理法可快速合成均匀、精细的FAU沸石粉体。在800 ~ 1000*的温度下，由氧化铝-二氧化硅凝胶、Al_2O_3、NaF、MgF_2和MgO的混合物进行固相反应，得到了化学成分不同的钠氟云母。所得氟云母结晶度高，呈薄板状，晶粒尺寸均匀。这些由铁渣转化而来的材料已被证实具有与商业材料相同或更高的性能。

Recently additional reuses of iron slags have been desired to develop the recycling process. In this study, the conversion process from iron slags to some high-performance alumino-silicates having higher functions, i.e. FAU zeolites, X and Y, and fluoro-micas, were developed. Silica gel as the starting material was prepared from water quenched blast furnace slag by pretreated with concentrate hydrochloric acid. Alumino-silica gel controlling the Si/Al ratio was also prepeared slow cooled blast furnace slag by pretreated with dilute hydrochloric acid. The acid treatments were rapidly carried out by using microwave heating method. FAU zeolites, type X and Y, having Si/Al = 1.3 - 9.5 were synthesized hydrothermally from the mixture of the two gels, NaAlO^2 and NaOH solutions in satisfactory yields. These products of zeolite X and Y show large specific surface areas, ca.730 m^2 g and ca. 875 m^2 g of Langumuir adsorption, respectively. Hydrothermal treatment by microwave heating has revealed to be a rapid method for synthesizing a homogeneous and fine FAU zeolite powders, compared with a direct heating method. Sodium-fluorine phlogopites having various chemical compositions were also obtained from the mixture of the alumino-siica gel, Al_2O_3, NaF, MgF_2 and MgO by solid-state reactions at 800 - 1000*. The obtained fluoro-micas showed the high crystallinity, thin-platy morphology and homogeneous grain size. These materials converted from iron slags have been confirmed to have equal and/or highly abilities compared to the commercial ones.