Development of fertilizer carriers based on zeolites and clays.
Fertilizers,zeolite, clay, hydroxyapatite, ion exchange, potassium, nitrogen.
Conventional fertilizers have their efficiency limited by problems such as volatilization, leaching and/or immobilization in soils, which can be minimized by the use of carriers based on zeolites and clays subjected to cation exchange with potassium chloride solution for slow release of potassium and through the use of composites based on hydroxyapatite and zeolite for controlled nitrogen release. The materials were characterized by XRD, XRF and FTIR. Samples of zeolites and clays subjected to cation exchange were tested in soil columns for slow release of potassium quantified by ICP-OES. The tests showed that the LTA zeolite has a higher adsorption capacity for potassium, in addition, the potassium in these samples is released continuously and gradually over time. The composite samples presented a polycrystalline nature evidenced by the XRD data where it is possible to observe the presence of peaks referring to LTA zeolite, urea and hydroxyapatite that presents two crystalline phases one monoclinic and another hexagonal identified through refinement, but the samples need an analysis of SEM to observe the morphology and characteristics of the materials obtained and to carry out nitrogen release tests to verify the feasibility of using the composite as a slow release fertilizer.