利用铬铁废渣制备黑色陶瓷釉

Preparation of Black Glaze Using Ferrochromium Slag Waste

利用铬铁废渣为Fe和Cr元素的致色前驱体制备了环境友好型黑色陶瓷釉。结果表明:黑釉中发色晶体为Fe–Cr–Co型混合尖晶石,黑釉中由于其尖晶石结构中Fe^(3+)的d–d跃迁、Co^(2+)的~4A_2(F)→~4T_1(P)跃迁以及Cr^(3+)的~4A_(2g)→~4T_(2g)跃迁,在可见光波长范围内吸收所有可见光,外观为黑色。随着烧成温度的增加,黑釉中主晶相及色度值无明显变化,表现出较好的高温稳定性。黑釉在酸和碱的浸蚀96 h下质量损失小于0.1%,表现出较好的耐化学性。黑釉中Cr元素以3价的形式存在,因此,利用铬铁废渣制备的黑釉中Cr的存在形式是无害的。

An environmental-friendly black glaze was prepared with a ferrochrome slag waste as chromium and iron precursors. The glaze with a black color could be obtained when a composite of Fe2O3 and Co2O3 was added. The color agent in black glaze is Fe-Cr-Co mixed spinel. Based on the result by ultraviolet-visible spectrophotometry(UV–Vis), the intensity of black color in glaze is related to the presence of d–d transitions of Fe3+, 4A2(F)→4T1(P) of Co2+, and 4A2 g→4T2 g of Cr3+ in spinel structures, practically absorbing in the whole visible region for the appearance of black color. The main crystal phases and color parameter of the prepared black glaze change slightly when the firing temperature increases, indicating a high-temperature stability. The black glaze has a chemical resistance against acid and alkaline attack after 96 h, showing a mass loss of less than 0.1% in mass. The results by X-ray photo electron spectroscopy show that Cr existing in the black glaze presents a trivalent state, indicating that the existence of Cr in the black glaze prepared by ferochromium slag waste could be harmless.