A Review on Slow-Release Coated Urea Synthesis, Coating Materials and Methods
Laiba Muneer1, Marcelo Fossa da Paz2*
1 Department of Chemistry, University of Agriculture Faisalabad, Pakistan
2 Faculty of Biological and Environmental Sciences, Federal University of Grande Dourados, Brazil
Submitted: 21-08-2025; Accepted: 27-12-2025; Published: 31-12-2025
Abstract
The rapid growth of the Earth’s population is forcing agricultural sector to use greater amounts of fertilizers to fulfil requirement of food, which in result increasing production costs. When urea is applied to crops it is more receptive to losses due to leaching and volatilization. The use of traditional urea often decreases Nitrogen Use Efficiency (NUE), therefore lowering crop’s yield and conferring to environmental challenges which include water eutrophication and air pollution. Urea efficiency can be enhanced by encasing it with slow-release coatings that reduces urea volatilization. This review explains the research on urea coatings including mechanisms such as sulfur-based coatings, zinc-based coatings, polymer-based coatings, bio-composite coatings, and superabsorbent coating materials, In addition to coating methods, this article also addresses nutrient release mechanisms, along with an analysis of future prospects. It further presents an overview of the limitations of conventional urea and the requirements for coated urea. This work concludes that slow-release fertilizers increase nitrogen use efficiency (NUE), reduce nutrient loss, and control environmental pollution by limiting volatilization and leaching, maintaining crop productivity with reduced fertilizer application rates and improving agronomic safety. Future research will improve nitrogen use efficiency via slow- or controlled-release coating technologies. Because current coating materials harm the environment and economy, biodegradable polymers like starch are good alternatives. More research on new coatings, field evaluations, standardized procedures, and scale-up methodologies are needed for the practical and commercial implementation of slow-release fertilizers.
Keywords: slow-release urea, Urea Coating, urea release mechanism, coating methods, nitrogen use efficiency
Full length article *Corresponding Author, e-mail: marcelopaz@ufgd.edu.br, doi# 10.71111/Science today/7-25-3-3-st-7