PHYSICAL-CHEMICAL PROPERTIES OF NMgCa-FERTILIZERS OBTAINED ON THE BASIS OF AMMONIUM NITRATE AND VERMICULITE

Although ammonium nitrate (AN) ranks second after urea among nitrogen fertilizers in terms of production and application volume, it remains the leading agent regarding plant nutrient uptake efficiency. This is primarily because nearly the entire total nitrogen content is assimilated in both ammonium (NH4+) and nitrate (NO3-) forms. However, the widespread agricultural utilization of AN is significantly constrained by several disadvantageous factors, including its physiological acidity, high hygroscopicity, caking tendency, low granule strength, thermal instability, and high explosive hazards. In this study, to enhance the commercial and physical-chemical properties of AN, a vermiculite mineral modifier was incorporated. The chemical composition and physical-chemical characteristics of the resulting complex nitrogen fertilizer samples, such as crystallization temperature, pH value, viscosity, porosity, and diesel oil absorption capacity, were comprehensively determined and evaluated.The experimental results demonstrated that the incorporation of vermiculite mineral into the ammonium nitrate composition increased the granule strength from 6.04 MPa to 7.85 MPa. For comparison, these values are equal to 1.32 MPa and 1.58 MPa for "pure" NH4NO3 and magnesite-modified ammonium nitrate, respectively. Furthermore, it was established that the dissolution time of the granules significantly prolonged (ranging from 84.83 to 117.55 s) compared to that of "pure" NH4NO3 (44.60 s) and magnesite-modified ammonium nitrate (46.80 s) granules.