METHOD OF PRODUCING IRON OXIDE PIGMENTS Russian patent published in 2013 - IPC C09C1/24 

FIELD: chemistry.

SUBSTANCE: to obtain iron oxide pigments, iron oxide sludge, which is a water treatment waste, is dried, calcined and ground. The water treatment wastes used are ferruginous underground water with iron content of not less than 42%. Calcination is carried out by gradually heating the dried iron oxide sludge either to temperature of 600°C in order to obtain a chocolate brown pigment, or to temperature of 800°C in order to obtain a bright red pigment, or to temperature of 1050°C in order to obtain a black pigment. Once the required temperature is reached, the calcination device is turned off.

EFFECT: invention enables to recycle wastes of water treatment plants to obtain iron oxide pigments for coloured concrete, paving slabs, prime coats, enamel and paints.

2 cl, 1 dwg, 3 tbl, 3 ex