Application of a modified method of humic acids extraction as an efficient process in the production of formulations for agricultural purposes

Due to their properties, humic acids (HA) can interact with macro- and micronutrients and retain plant nutrients in the soil profile. The aim of the presented work was to develop a new integrated 4-step process for the isolation of humic acids from peat with their simultaneous enrichment in macronutrients. The study demonstrated the possibility of replacing traditional solutions used in the extraction of humic acids with solutions that are a source of macronutrients. For the alkaline extraction step, a process assisted with ultrasound was implemented, which allowed to increase the efficiency of humic acids isolation. Optimization of this step has shown that, with the application of ultrasound in the new procedure, it is possible to obtain the humic acids isolation efficiency of more than 60%. The qualitative analysis of the products obtained confirmed the presence of structures characteristic of humic acids, including key functional groups.