METHOD OF PRODUCTION OF BLACK IRON OXIDE PIGMENT Russian patent published in 1999 - IPC

FIELD: production of pigments from bog iron ores applicable in paint and varnish industry for painting of building materials, in capacity of fillers in production of plastics, rubbers, linoleum and other articles, in printing, in painting. SUBSTANCE: bog iron ores contain, wt.%: goethite, hydrogoethite, 60-90; organic detritus 10-15; amorphous phosphorus, 3-5; water, 8-14. Ores are roasted in reducing medium at 400 ± 10 C in presence of mineralizing additive in form of sodium chloride which is introduced in amount of 2% of total weight of ore. EFFECT: provision of production of black iron oxide pigments with improved painting and technical properties. 1 tbl, 10 ex