Use of Polysulfone in Controlled-Release NPK Fertilizer Formulations

Abstract

Encapsulation of fertilizers in polymeric coatings is a method used to reduce fertilizer losses and to minimize environmental pollution. Polysulfone was used for a coating preparation for soluble NPK granular fertilizer in controlled-release fertilizer formulations. The coatings were formed by the phase inversion technique (wet method). The influence of the polymer concentration in the film-forming solution on the physical properties of the coatings was examined. The coating structure controls the diffusion of the elements from the interior of the fertilizer granule. It was experimentally confirmed that the use of polysulfone as a coating for a soluble fertilizer decreases the release rate of components. Moreover, the release rate of nutrients from coated granules decreases with the decrease of the coating porosity. In the case of coating with 38.5% porosity, prepared from 13.5% polymer solution after 5 h of test, 100% of NH(4)(+) was released, whereas only 19.0% of NH(4)(+) was released after 5 h for the coating with 11% porosity. In addition, coating of fertilizers leads to improvement of handling properties, and the crushing strength of all coated fertilizers was an average 40% higher than that for uncoated NPK fertilizer.

Combination of agricultural waste compost and biofertilizer improves yield and enhances the sustainability of a pepper field

“…Moreover, mixture of BF and organic fertilizers showed even more remarkable advantages in growth promotion in 60 d, suggesting that the combination of BF and organic fertilizers support plant growth in the long term better than the BF+IOF treatment. The result that the growth of pepper plants in BF+IOF is comparatively faster in the first 30 d and slows down in the later 30 d is in accordance with the report of Tomaszewska and Jarosiewicz (), that a majority part of chemical fertilizer is released to the soil within 5–30 d after application.…”

Role of Slow-Release Nanocomposite Fertilizers on Nitrogen and Phosphate Availability in Soil

“…Concomitantly, quantifications were performed for tests involving pure Hap and SSP as a control experiment. Urea release experiments were performed parallel with phosphorus solubilization tests according to the method adapted from Tomaszewwska and Jarosiewicz35. The concentration of urea in solution was determined by UV-Vis spectrophotometer (Shimadzu-1601PC).…”

Controlled release of nitrogen‐source fertilizers by natural‐oil‐based poly(urethane) coatings: The kinetic aspects of urea release

“…7,8 It should also have a hardness that effectively protects the substrate (fertilizer), with good resistances to mechanical abrasion and moisture permeation. 9 In the specialized literature, some studies have been reported that propose various materials to coat nutrients. 10 However, in general, the recommendations indicate thick coatings, which reduce the total amount of nutrient present in the granule.…”