Based on the results of experimental studies, a method has been developed for obtaining a liquid complex fertilizer, which has a low bulk density, viscosity and crystallization temperature. The results of a study of the physicochemical parameters of obtaining liquid fertilizer NPCa are presented. A liquid complex fertilizer in a basic solution obtained on the basis of a neutralized liquid phase of a nitric acid extract with monoethanolamine and ammophos was dissolved ammonium nitrate granules.

Objective: This study aimed to evaluate the feasibility of producing suspension NPK fertilizers from wet-process phosphoric acid (WPA), sunflower ash, and ammonium nitrate, characterize the elemental composition of the starting materials, and estimate raw material requirements for formulations with different nutrient compositions. Methods: Wet-process phosphoric acid and two ash samples were characterized using X-ray fluorescence (XRF) spectroscopy. Five suspension NPK fertilizer samples were analyzed for their main nutrient components following sample mineralization, using photometric methods. Elemental phosphorus and potassium concentrations were converted into their corresponding P₂O₅ and K₂O equivalents. Theoretical raw material requirements were estimated using nutrient-based mass balance equations. Results: The potassium contents of the two sunflower ash samples were 29.30% and 26.10%, corresponding to K₂O equivalents of 35.29% and 31.44%, respectively. The elemental phosphorus content of WPA was 8.82%, equivalent to 20.21% P₂O₅. The five NPK suspension samples exhibited reported N–P₂O₅–K₂O compositions of 9–12–4, 11–11–11, 10–9–4, 8–7–5, and 7–7–6, respectively. Among the investigated formulations, NPK-2 had the highest reported combined nutrient content of 33%. For a target formulation of 100 g of NPK 11–11–11 fertilizer, theoretical nutrient-balance calculations indicated approximate requirements of 53.25 g of WPA, 34.91 g of sunflower ash, and 32.35 g of ammonium nitrate. However, the calculated total input mass exceeded the target product mass, indicating the need for experimental validation of the overall mass balance. Conclusions: The findings indicate the potential of sunflower ash as an alternative potassium source for suspension NPK fertilizer formulations in combination with wet-process phosphoric acid and ammonium nitrate. Nutrient-based calculations provide a preliminary basis for estimating raw material requirements. Further investigations are needed to verify the actual mass balance, confirm the total nitrogen content, and evaluate suspension stability and agrochemical properties before establishing a validated production formulation.