Sulfur enriched slow-release coated urea produced from inverse vulcanized copolymer

Synthesis and performance evaluation of slow-release fertilizers produced from inverse vulcanized copolymers obtained from industrial waste

“…This method involves the usage of color reagent, which was prepared by mixing the 25 ml of DAM solution (prepared by dissolving 2.5 g of diacetyl monoxime in 100 ml of distilled water), 15 ml of TSC solution (prepared by dissolving 0.25 g of thiosemicarbazide in 100 ml of distilled water) and 460 ml of acid reagent (prepared by mixing 10 ml of sulfuric acid, 240 ml of distilled water and 250 ml of phosphoric acid). 20,21,28 2 g of coated urea was placed in a conical flask containing 200 ml of distilled water. To estimate the amount of the nitrogen released in distilled water from coated urea, after every 24 h 2.5 ml of the aliquot was taken and mixed with 7.5 ml of the color reagent and heated to a temperature of 85 °C for 30 min in a water bath followed by cooling at room temperature.…”

“…The obtained red color solutions were then analysed using Shimadzu UV-1800 UV-Vis spectrophotometer at 526 nm wavelength. 13,20,21…”

“…For biodegradability test same procedure was followed as explained in our previous reports. 13,20,21…”

“…Coated urea was produced using a dip-coating method, for which 4 g of produced copolymer was overnight dissolved in 4 ml of chloroform solvent to obtain homogenous coating solution. 20,21,26 Aerwards, 8 g of urea granules (2-2.5 mm) was added in coating solution and carefully mixed using glass rod to ensure the uniform coating of the urea, followed by overnight drying. Same process was repeated twice or thrice to obtain different coating thickness.…”

“…These copolymers have already been utilized in several application which includes Li-S batteries, water purication and CO 2 capturing. Recently Ghumman et al, 13,20,21 utilized inverse vulcanized copolymer prepared from Jatropha and rubber seed oil as a coating material for urea to produce SRFs. The produced SRF demonstrated promising results in terms of biodegradability and nutrient release efficiency.…”