生物质基缓释尿素的制备及其缓释性能研究OA

The existing slow-release urea commonly faces issues such as high production costs and environmental pollution caused by degradation products,which limit their application in agricultural production.Consequently,developing efficient and cost-effective slow-release urea with environmentally friendly characteristics is the direction for the development of slow-release fertilizers.Biomass-based slow-release urea(B-SRU)was prepared by physical mixing,using four biomasses with different growth forms as raw materials.The differences in slow-release performance of different B-SRU were systematically compared and analyzed.The results show that the slow-release performance of different B-SRU exhibits significant variations in response to preparation temperatures due to the differences in structures and compositions of biomass raw materials.With the increase of preparation temperatures,the slow-release performance of herbaceous B-SRU gradually improves and the urea release rate can be reduced by 33.01％.The slow-release performance of woody B-SRU shows a gradually decreasing trend,and the slow-release performances of vine and hemp B-SRU show"V"and inverted"V"patterns in change,respectively.SEM and FTIR characterization results confirm that the binding mechanism between biomass and urea is mainly a dual action of physical dense wrapping and hydrogen bonding network.The release kinetics analysis shows that the release of urea from B-SRU is mainly dominated by classical Fick diffusion,and the urea molecules mainly migrate by diffusion through the physical pores of the biomass matrix.