Biodegradation of Yerba Mate Waste Based Fertilizer Capsules: Effect of Temperature

Abstract

Yerba mate waste based urea fertilizer capsules were obtained and characterized. Yerba mate powder (YMP) content in these encapsulation systems ranged from 52 to 82% for the diferent formulations. The aim of the study was to evaluate the efect of yerba mate powder:calcium alginate ratio and the assay temperature on capsule degradation and urea release rate in soil. Degradation evolution was monitored by microbiological tests, environmental scanning electronic microscopy, diferential scanning calorimetry and Fourier transform infrared spectrometry. Encapsulation efciency increased with YMP content. The green fertilizing systems generated did not inhibit microorganism development in soil. Degradation was slower for capsules with higher YMP content. Capsules with high YMP content released lower amounts of urea. Both degradation and release rates increased with assay temperature. The recycling of yerba mate powder as a green composite material originateda new fertilizer system.