Effect of environmentally friendly organic solvent on nitrogen release and membrane properties of polymer coated controlled release urea

Polymer-coated controlled-release urea is widely used as controlled release nitrogen fertilizer in horticultural plants such as tropical banana or subtropical citrus because it can greatly improve nitrogen efficiency and reduce the amount of nitrogen fertilizers application and avoid topdressing. However, up to now, harmful haloalkanes are used as organic solvents in the traditional production of polymer-coated controlled-release urea. This poses harm to the environment, it is expensive and must be recycled. It is necessary to select a non-toxic and environmentally friendly green organic solvent as its substitute in production of polymer-coated controlled-release urea. In light of this issue, we designed an experiment in which we used halogenated hydrocarbon solvent (A) as the control, and harmless organic solvent (B) as the treatment. We prepared polymer-coated controlled-release urea samples with controlled-release periods of 85 and 40 days. Nitrogen release characteristics of these samples were then evaluated in 25 and 40°C of water medium cultures, and the chemical properties of coated materials were characterized by a SPECTRUM ONE FT-IR spectrometer. Our results showed that there were no differences in the nitrogen release characteristics of controlled-release urea produced between different organic solvents (A) and (B) with the same coating material. Meanwhile, the chemical characterization results of the same controlled release urea membrane were identical. These results proved that harmless organic solvent (B) can be used as a green substitute for harmful halogenated hydrocarbon solvent (A) in production of polymer-coated controlled-release urea in horticultural plants in the world.