Uzoh, Chigozie FrancolinsChigozie FrancolinsUzohPietsch-Braune, SwantjeSwantjePietsch-BrauneLindmüller, LennardLennardLindmüllerHeinrich, StefanStefanHeinrich2026-07-242026-07-242025-12-16Results in Engineering 29: 108716 (2026)https://hdl.handle.net/11420/64007The strict legal requirements in the European Union mandating biodegradable components in fertilizers by 2026 underscore the urgent need for innovative solutions in controlled release coated urea (CRCU) fertilizers. Despite the critical importance of optimizing coating materials and processes for CRCU fertilizers, a comprehensive review of optimization methods is notably absent, leaving a significant knowledge gap in the development of efficient and sustainable CRCU technologies. This review addresses this gap by providing an in-depth analysis of bio-based coating materials, encapsulation methods, and fluidized bed processes for CRCU fertilizers. We critically evaluate existing research, identify key challenges and opportunities, and discuss future directions for developing biodegradable and efficient CRCU fertilizers that meet the impending regulatory requirements. This review serves as a timely resource for researchers, industry stakeholders, and policymakers seeking to develop and implement sustainable coating solutions.en2590-12302025Elsevierhttps://creativecommons.org/licenses/by/4.0/Bio-based coating materialsCoated fertilizerControlled releaseDiffusion coefficientEncapsulationFluidized bed technologyProcess optimizationTechnology::620: Engineering::620.1: Engineering Mechanics and Materials ScienceReview Article10.1016/j.rineng.2025.10871610.15480/882.17571