METHOD OF PREPARING MAGNESIUM FERTILIZER Russian patent published in 2000 - IPC

FIELD: technology of preparing complex mineral fertilizers for agricultural and forestry purposes for magnesium-depleted acid podzolic soils and in chemical industry in manufacture of meliorative materials for preservation and restoration of forests under conditions of adverse effect of industrial discharges, more particularly acid rains. SUBSTANCE: original serpentine-containing product is ground to isolate fraction with particle size of less than 0.315 mm and heat treatment is carried out 6200660 C for 15-30 minutes prior to formation of forsterite. Original serpentine-containing product comprises, wt %: SiO₂, 34.67-42.80; TiO₂, 0.06-0.89; Al₂O₃, 2.12-8.67; Fe oxides in terms of Fe₂O₃, 1.12-9.78; MnO, 0.06-0.25; MgO, 25.37-38.80; CaO, 0.79-7.45; H₂O+ 9.08-12.58; impurities, the balance, MgO:SiO₂= 0.73-0.91; Fe₂O₃:MnO, 18.65-79.42. Method makes it possible to prepare complex mineral fertilizer comprising in addition to magnesium in form assimialle by plants, also manganese, iron and silica. Fertilizer makes it possible to neutralize excessive acidity of soils exposed to acid rains and has prolonged effect. EFFECT: more efficient preparation method. 3 cl, 5 ex, 1 tbl