FOAMED CARBAMIDE-FORMALDEHYDE FERTILIZER AND METHOD FOR ITS PREPARING

摘要

FIELD: chemistry, chemical technology, fertilizers.;SUBSTANCE: invention is used for preparing fertilizers. The proposed fertilizer comprises the following components, wt.-%: bound nitrogen, 30-32; free nitrogen, 0.2-0.3; P₂O₅, 0.35-0.40; K₂O, 0.0015-0.0020; MgO, 0.0035-0.0045 with the density value 8-25 kg/m³, water absorption index 330-400% and amount of opened pores 85%, not less. Method for preparing involves foaming the reaction composition comprising carbamide, formaldehyde, acid catalyst H₃PO₄, surface-active substance and tannic extract from conifer trees bark, its hardening (polycondensation) and drying. Invention provides preparing high-quality fertilizers.;EFFECT: improved preparing method, valuable properties of fertilizer.;8 cl, 2 tbl, 2 ex