A relationship between the structure and water purifying ability of waste glass prepared from household garbage and Fe 2 O 3 was examined by 57 Fe-Mö ssbauer and induced coupled plasma (ICP) measurements. From the Debye temperature of waste glass, Fe II proved to be loosely bound in the glass network as a network modifier. Dissolution amount of Fe III into artificial drain can be controlled from 0.14 to 0.35 mg/l by changing the Fe 2 O 3 content. It proved that chemical oxygen demand (COD) decreases in proportion to the content of Fe III , indicating that iron causes decomposition of organic and phosphorus compounds.Key words 57 Fe-Mö ssbauer spectra . Debye temperature . iron-containing silicate glass . chemical oxygen demand (COD)

Structural change of chrysotile caused by isothermal annealing and glassification was examined by 57 Fe-Mössbauer spectroscopy, X-ray diffractometry (XRD), X-ray fluorescence analysis (XRF), differential thermal analysis (DTA) and scanning electron micrography (SEM). From 57 Fe-Mössbauer spectra, it proved that Fe II in the pristine chrysotile was oxidized to Fe III when annealed at 1,000 • C. By contrast, Fe III was reduced into Fe II when annealed at 1,300 • C under in ambient atmosphere. Both forsterite (Mg 2 SiO 4 ) and fayalite ((Fe, Mg) 2 SiO 4 ) were precipitated when the chrysotile was annealed at higher than 1,000 • C. Homogeneous glass samples were obtained by melting asbestos with waste-glass powder, Na 2 CO 3 and K 2 CO 3 at 1,300 • C for 15 min. A constant isomer shift value of 0.23 ± 0.01 mm s −1 and an increase in the quadrupole splitting value from 0.70 ± 0.02 to 1.01 ± 0.02 mm s −1 were observed in the glassified chrysotile.

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