This low-cost, bio-based, biodegradable coating material provides controlled release of nitrogen or other nutrients from fertilizer for more than one month. Studies have shown that by controlling nutrient release, biodegradable polymer coatings can optimize nutrient usage and conserve long-term soil fertility. The global market for controlled-release fertilizers is projected to reach $3.9 billion by 2024 . Many slow-release fertilizer coatings are not biodegradable and persist in the soil which has undetermined long-term consequences. Additionally, current coating materials can add to bulk, reducing nutrient density, and increase both storage and handling costs.
Researchers at the University of Florida have developed a bio-based, lightweight, low-cost fertilizer coating suitable for large-scale applications.
Bio-based, biodegradable coating material for the controlled release of nitrogen from fertilizer
A bio-based polyurethane, lignin and clay coating is derived from renewable agricultural byproducts. Epoxidation and modification of lignin produces a nano lignin-clay hybrid, which modifies the bio-based coating material to improve its adsorptive and controlled-release properties. The environmentally sound fertilizer coating is completely biodegradable, environmentally friendly, but also provides prolonged release and adds very little bulk to the fertilizer prills thus minimizing storage and shipping costs.