The Effect of Ultrasonication Treatment in the Synthesis and Characteristics of Nano Potassium Sulfate and Potassium Chloride Fertilizer from Kepok Banana (Musa paradisiaca) Peel Extract

Kepok Banana (Musa paradisiaca) is widely consumed, but the peels cause waste accumulation if they are not effectively utilized. Kepok Banana (Musa paradisiaca) peels have a high potassium content. This research aims to determine the effect of ultrasonication treatment on the synthesis and characterization of potassium fertilizer in nanoform to enable plants to quickly absorb it. Various types of potassium-based fertilizer compounds include potassium sulfate and potassium chloride. In this research, extraction was carried out first to obtain K₂ CO₃ salt, which was then precipitated into potassium sulfate and potassium chloride with the help of sonication treatment to obtain nano-sized particles. Based on the results of the characterization using field emission scanning electron microscopy (FESEM) with energy dispersive X-ray spectroscopy (EDX), X-ray fluorescence (XRF) and transmission electron microscopy (TEM), ultrasonication treatment was found to reduce the particle size of K₂ SO₄ from 9.64 to 8.80 nm, while the particle size of KCl reduced from 22.69 to 21 nm. In addition, the presence of ultrasonication treatment reduced the potassium content in K₂ SO₄ from 28.10% to 27.50%, while in KCl, it was from 63.90% to 61.50%. However, the decrease in potassium content was relatively minor. The analysis using particle size analyzer (PSA) found that K₂ SO₄ and KCl fertilizers were not suitable for application in solution because they caused larger particle sizes due to the agglomeration process.