Copper-Modified Faujasite Zeolite Reinforcement in Biodegradable Starch Sachets for Potassium Fertilizer Releasing

Author(s)

Malafatti, Joao Otavio Donizette ; Sciena, Camila Rodrigues ; Paris, Elaine Cristina

• Document type: Journal article
• Source: Journal of Inorganic and Organometallic Polymers and Materials; v. N/A, p. 16-pg., 2025-06-10.

Abstract

Fertilizers are a class of agrochemicals essential to improve the nutritional soil quality and crop production. One challenge in the fertilizer application is controlling the losses from leaching and aerial dispersion, being an economic and environmental issue. A promisor alternative is the use of fertilizer systems that guarantee adequate packaging and posterior release when in contact with the target desirable. In this sense, biodegradable starch sachets are an interesting system for packaging and fertilizer delivery. The great advantage is the nutritional composition adequation inside the sachets to attend to the demands, not affecting the biopolymer matrix processing. Thus, the present work aimed to develop a multifunctional system based on a starch sachet reinforced with copper-faujasite zeolite (Cu-FAU) for potassium packaging. Besides, the innovation consists in evaluating the availability of the copper and nitrogen (urea) present in the polymeric matrix, as secondary nutrition sources. The starch matrix was plasticized in the presence of urea and citric acid, following the sachet molding applying a pressing. The results indicate that the addition of citric acid 3% (w w-1) increased the water vapor barrier and the tensile strength. Urea and Cu2+ ions release occurred partially, once the sachets were preserved in an aqueous medium for 30 days. Concerning chloride potassium (soluble salt), the higher hydrophilicity of sachets favored a quick opening of the packaging, dissolving it when in contact with the external environment. Furthermore, the Cu-FAU showed fungistatic activity against Alternaria alternata fungus. This result indicates that the copper could control the degradability of the sachets until the soil application. Thus, the starch sachets demonstrated an easy way to package the potassium and facilitate the manipulation during the storage, preserving the higher solubility properties for a posterior release. (AU)

• FAPESP's process: 21/14992-1 - Obtainment of nanocomposite membranes consisting of PCL/PMMA/zeolite for application as a chemical sensor in the detection of polyphenol residues from the coffee industry
• Grantee: João Otávio Donizette Malafatti
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 23/03632-0 - Development of sensor arrays based on zeolite nanostructures functionalized with porphyrins for polyphenol detection
• Grantee: João Otávio Donizette Malafatti
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 19/09485-3 - Processing of starch composite with CuO nanoparticles for fungicide application and controlled release of Cu 2+ ions
• Grantee: Marcelo Avila Domingues
• Support Opportunities: Scholarships in Brazil - Scientific Initiation