Urea fertilizer coated with biodegradable polymers and diatomite for slow release and water retention

Abstract

Slow release fertilizers (SRFs) are of vital importance to improve agricultural efficiency. However, their use is still limited due to their relatively high costs. Additionally, most of coating materials used to produce SRFs are nonbiodegradable and toxic to the soil. In this context, we utilized various biopolymers such as tamarind, xanthan, and guar gums together with diatomite to coat urea fertilizer granules. In this study, tamarind-urea-diatomite (TUD), guar-urea-diatomite (GUD), and xanthan-urea-diatomite (XUD) SRF granules were prepared in the presence of epichlorohydrin as crosslinker. The nutrients slow release behavior and the water retention capacity of these SRFs in soil were determined. The water absorbency of the product was 89% TUD, 93% GUD, and 142% XUD of its own weight when it was allowed to swell in tap water at room temperature for 2 h. Poly(methacrylic acid) was applied as the outermost layer of XUD to improve the nitrogen slow release efficiency of XUD SRFs. The results showed that the product had an excellent nutrients slow release property of 79.5% and good water retention capacity of 62.9% after 28 days. This suggested that XUDM could effectively improve the utilization of fertilizer. Furthermore, being biodegradable and low cost could be beneficial in agricultural and horticultural applications.

Bioremediation: Perspectives of the use biopolymers systems for slow release nutrients

“…Authors who have worked with modified cellulose have observed 35% higher nutrient retention than the uncoated system (19,110). In addition to crosslinking and chemical modification, the use of double-coating systems may be a strategy to improve the nutrient release profile (115). In a double coat system with crosslinked starch, as an outer layer and ethylcellulose (EC), as the inner layer, the modified cellulose provided to the system a better balance on the hydrophilic and biodegradable properties of the starch (19).…”

Controlling radiation degradation of aCMCsolution to optimize the swelling of acrylic acid hydrogel as water and fertilizer carriers

“…Several previous instances in literature had revealed that when urea is added to the soil, it goes through a series of biological, physical, and chemical transformations to produce sufficient plant nutrients 11 . Moreover, its release of nutrients is influenced by several factors such as assoil pH, temperature, fertilization location, dose coverage, organic matter, and Cation Exchange Capacity CEC that would result in loss of fertilizers and nutrients.…”

Valorization of Superabsorbent Polymers from Used Disposable Diapers as Soil Moisture Conditioner

“…A major advantage of using SAP is its ability to make use of moisture present in soil such as clay, and make it available to the roots. SAP amended soils have better nutrient release, high nitrification, reduced microflora and bacterial content [29][30][31].…”