METHOD OF PREPARING IRON OXIDE PIGMENT Russian patent published in 1998 - IPC

FIELD: manufacture of inorganic iron oxide pigments, more particularly paints, enamels, painting of plastic materials, linoleum, and paper. SUBSTANCE: invention describes method of iron oxide pigment using, as original stock, spent iron oxide catalyst waste resulting from dehydrogenation of olefinic or alkylaromatic hydrocarbons. The method comprises calcining it in steam at 600-670 C for 1 to 3 h and subsequently cooling in air vapor or nitrogen vapor mixture used in 35:1-1.35 wt.ratio by weight at rate of 25-35 C/h to 200-300 C and then in nitrogen and/or air at rate of 25-35 C/h to 40-80 C, and the resulting pigment is dried and ground. EFFECT: improved properties of oil resistance, cover power and heat resistance. 1 ex, 1 tbl