Synthesis and study of the agrochemical properties of urea salts with nitric and orthophosphoric acid

The paper presents the results of the synthesis, IR spectroscopic and agrochemical study of the products of adduct formation (internal salts) of urea with nitric and orthophosphoric acids. It has been established that the synthesized substances are hygroscopic, readily soluble in water. IR spectral data indicate that, depending on the “acid : urea” ratio in the final products CO, NH2, urea groups and acid molecules are involved in the formation of various compositions: [H 2 O···(NH 2 ) 2 C(OH) +···- ONO 2 ] and [O 2 N-O -···+ H 3 N(H 2 N)C(OH) +···- O-NO 2 ], [-NH 3 +···-O-P(O)(OH) 2 ] and [C(OH) +···- O-P(O)(OH) 2 ] salt bridges. The solubility of poorly soluble salts, which are included in a series of metal ion compounds accumulating in the soil under the action of urea mononitrate, has been studied. According to the results of an agrochemical study of the effect of synthesized urea salts on the digestibility of P2O5 by Tr-B and citric acid in the soil, an increase in these parameters under the action of urea dinitrate and diorthophosphate was found to be within 8.26–11.52 and 8.28–9.52%, relative to control 1.07 and 0.787%, respectively.