Green Synthesis of Potassium Nanofertilizer from Agricultural Byproducts

An investigation was carried out to synthesize and characterize potassium nanofertilizer in a green and environment-friendly way from stems and peels of banana (cultivar. Malbhog). In order to create a nanofertilizer extract from banana stem and peel, a specific amount of commercial-grade potassium hydroxide was added (4, 7, 10, 15, 20 g/kg specimen). A nutrient analysis of the extract from the stems and peels of bananas showed that as the amount of potassium hydroxide in the extract increased, the amount of macronutrients, micronutrients, and organic compounds also increased. The highest N, P, K, Ca, Mg and Na contents in the stem extract were 0.70%, 0.55%, 5.10%, 1.83%, 2.10% and 1.90%, respectively, whereas in the peel extract, the highest N, P, K, Ca, Mg and Na contents were 1.40%, 0.50%, 4.59%, 1.89%, 2.31% and 2.20%, respectively. Similarly, the highest Fe, Cu, Zn, B and Mn contents of the stem were 315.15 ppm, 4.80 ppm 0.31 ppm, 0.19 ppm and 6.60 ppm, respectively. The highest contents of the micronutrients Fe, Cu, Zn, B and Mn in the peel extract were 350.02 ppm, 5.10 ppm, 0.30 ppm, 0.20 ppm and 6.70 ppm, respectively. There was a significant quantity of organic compounds in the extracted fertilizer. Dynamic Light Scattering technique (DLS) revealed that the minimum sizes of the nanopotassium in the stem and peel extracts were 40.8 nm and 39.4 nm, with 43.59% and 100% intensities, respectively. Transmission Electron Microscopy (TEM) images contributed to the findings showing nanospherical structure, with the smallest size of the nanoparticles in the stem being 25 nm, and that in the peel extract being 18 nm