METHOD OF PRODUCING HEXAHYDRATE OF MAGNESIUM NITRATE THROUGH COMPLEX PROCESSING SERPENTINITE Russian patent published in 2010 - IPC C01F5/38 

FIELD: chemistry.

SUBSTANCE: invention relates to chemical industry and can be used in producing hexahydrate of magnesium nitrate. At the first step, serpentinite is leached with a 20-25% solution of nitric acid. The obtained pulp is filtered to form a filtrate and a residue. The filtrate is evaporated and cooled and the residue from evaporation is treated with water while stirring. The formed suspension is filtered. The filtrate is evaporated and then cooled to room temperature for crystallisation of the hexahydrate of magnesium nitrate. The residue from filtering the suspension is washed with water to obtain flush water. The residue from filtering pulp is taken to a second leaching step with a 30-35% solution of nitric acid. The obtained pulp is filtered, the filtrate is evaporated and cooled to room temperature and the residue from evaporation is treated with water while stirring. The formed suspension is filtered. The filtrate is evaporated and cooled for crystallisation of the hexahydrate of magnesium nitrate. The residue from filtering the suspension is washed with water to obtain flush water which is then mixed with the filtrate after the second leaching step.

EFFECT: invention increases magnesium extraction ratio and improves quality of the obtained hexahydrate of magnesium nitrate.

4 cl, 1 dwg, 3 ex