|Budget Amount *help
¥3,400,000 (Direct Cost : ¥3,400,000)
Fiscal Year 1998 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1997 : ¥2,900,000 (Direct Cost : ¥2,900,000)
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.