![]() ![]() This provides an innovative way to deal with toxic chromium-containing solid wastes, so it is necessary to study the effect of Cr 2O 3 on glass–ceramics crystallization. The research results of Zhao and others show that Cr 2O 3 is an effective nucleating agent for the preparation of glass–ceramics of the pyroxene class. The proper amount of nucleating agent can promote the overall crystallization of the glass–ceramics, improve the crystallization efficiency, and shorten the crystallization time, which can ensure that the ideal microstructure and excellent physical and chemical properties of the glass–ceramics are obtained. When the glass–ceramics of the pyroxene class of CaO–MgO–Al 2O 3–SiO 2 system were prepared by melting method, it was necessary to add nucleating agent. Similar to other glass–ceramics, the crystals in glass–ceramics of the pyroxene class are formed by the controllable crystallization of glass. Glass–ceramics of the pyroxene class have the advantages of high hardness and chemical corrosion resistance, and are usually used as building decoration materials. ![]() The leaching concentration of chromium meets the Chinese national standard, indicating that diopside glass–ceramics can effectively solidify the heavy metal chromium, and this fact makes the application of glass–ceramics feasible. When the mass percentage of Cr 2O 3 reaches or exceeds 1.60%, Cr 3+ preferentially forms the magnesia chrome spinel phase, which further induces the in situ growth of diopside. When the mass percentage of Cr 2O 3 in glass–ceramics is less than 1.60%, a small amount of diopside phase is precipitated during heat treatment, and Cr 3+ is dispersed in the diopside phase. The results show that chromium is present in glass–ceramics as Cr 3+ and Cr 6+, and Cr 3+ accounts for more than 80% of the chromium contents. The effect of Cr 2O 3, a nucleating agent, in the crystallization process of diopside glass–ceramics was studied. The prepared glass–ceramics were characterized by differential thermal analysis (DTA), X-ray diffraction (XRD),scanning electron microscopy (SEM), energy-dispersive spectrometer (EDS), and X-ray photoelectron spectroscopy (XPS). CaO–MgO–Al 2O 3–SiO 2–Cr 2O 3 diopside glass–ceramics were prepared from blast furnace slag, low-carbon ferrochromium alloy slag, and quartz sand by the melting method. ![]()
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