Multilayer films for fertirelease materials based on carboxymethylcellulose/chitosan/zeolites-fertilizers

Author(s)

Tamires dos Santos Pereira

• Document type: Master's Dissertation
• Press: Pirassununga.
• Institution: Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT)
• Defense date: 2020-03-26

Examining board members

Roselena Faez; Fauze Ahmad Aouada; Mariana Altenhofen da Silva

• Advisor: Roselena Faez

Abstract

The scientific community has intensified studies on new materials to use their properties in the manufacture of enhanced efficiency fertilizers. These materials are attractive because they release the essential nutrients to plants on a prolonged way. In addition, they reduce environmental damage, increase practicality during the application, reduce fertilizer consumption and increase productivity. Thus, this work aimed to obtain and characterize enhanced efficiency fertilizers based on natural zeolite (Ze) adsorbed with macro and micronutrients, carboxymethylcellulose (CMC) and chitosan (Ch). Initially, we evaluate the adsorption capacity of Ze in relation to the potassium (KNO3), copper (CuSO4·5H2O), manganese (MnSO4·H2O), zinc (ZnSO4·7H2O) and iron (FeSO4·H2O) nutrients. Additionally, kinetic studies and adsorption isotherms were performed. After the adsorption process, nutrient-enriched Ze was incorporated into the CMC solution to obtain mono and multi-elemental films by solvent evaporation (casting). Additionally, multilayer films containing Ch or CMC-Ze-micronutrients were prepared. Ze shows higher selectivity for Cu2+ and Zn2+ ions over Fe2+ and Mn2+ ions, in agreement with the physicochemical properties of the ions. Multilayer composite films containing only CMC significantly decreased water release for all nutrients used. In the second stage, soil release tests were performed. The single and multi-element multilayer films were produced by pressing. Soil analyzes lasted 80 days. The Basacote® commercial fertilizer was also evaluated with the objective of comparing the release data between the proposed materials. The results showed that the developed materials present similar results to the commercial one in relation to the release of macro and micronutrients. The films obtained in this work have the potential of commercial application, due to the low cost and simplicity of production, giving to the materials added value and environmental, because they contribute to more sustainable agricultural practices. (AU)

• FAPESP's process: 18/03235-2 - Multilayer films based on carboxymethylcellulose/chitosan/zeolites/fertilizers for ferti-release materials
• Grantee: Tamires dos Santos Pereira
• Support Opportunities: Scholarships in Brazil - Master