Effect of Chitosan Gelatinization Temperature on Water Absorption and Water Retention of Chitosan-Based Urea Fertilizer

Abstract

Chitosan has a high potential to be blended together in urea fertilizer for slow release properties due to its unique polymeric cationic character and gel-forming properties. In agriculture, the slow release properties are normally indicated by the ability of urea fertilizer to absorb and retain water, since nitrogen is released to the environment once urea is in contact with water or enzyme. This paper investigates the effect of the chitosan content and gelatinization temperature on the physical properties of chitosanbased urea fertilizer. The chitosan content was varied from 0, 3, 5, 7 and 10 pph. Chitosan-based urea fertilizer was prepared through a direct wet mixing using a laboratory setup consisting of a beaker, magnetic stirrer and hotplate. The properties of chitosan-based urea fertilizer were compared at two different mixing temperatures which are 60 o C and room temperature of 25 ± 3 o C. The mixture was then dried in an oven at 60 o C for 8 hours before being fabricated into pellets using a hydraulic hand presser. Water absorption and water retention analysis were carried out to measure the amount of water intake and the amount of water retained in the fertilizer. It was observed that mixing temperature has a negligible effect on the water retention of the fertilizers. However, gelatinization at room temperature resulted in fertilizers with better water absorption and water retention properties than the one gelatinized at 60C. These results were supported by X-ray diffraction (XRD) analysis conducted on the fertilizers. As a conclusion, the gelatinization temperature plays an important role in improving the water retention and water absorption capability of chitosan-based urea fertilizers. Furthermore, the presence of chitosan improved the crystallinity of the urea fertilizers, as indicated by XRD analysis.

Synthesis and characterization of zeolite based nano–composite: An environment friendly slow release fertilizer

“…50.0 g sieved soil from field was taken in cup A and in cup B 2.0 g of ZNC was taken after mixing with 50 g soil followed by addition of 30 ml distilled in each cup. Water was allowed to seep through them and cups were reweighed (W A1 and W B1 ) after 24 h. The cups were then kept in a glass box and weighted (W A2 and W B2 ) daily for next 30 days allowing 24 h interval between the readings [31]. The following equation (Eq.…”

Properties of Controlled-Release-Water-Retention Fertilizer Coated with Carbonaceous-g-Poly(acrylic acid-co-acrylamide)Superabsorbent Polymer

“…MBA acts as a cross-linker agent was added in the monomer solution and was stirred at room temperature until the MBA was completely dissolved. The flask then was immersed in a water bath and heated up to 70 º C and then APS initiator was added to the solution that was magnetically stirred at 300 rpm [19]. The reaction mixture was left to stir for 2 hours until gel point before the resulting SAPs was removed from the reaction and dried overnight in oven at 60 º C. The dried sample was then further crushed using ball mill and sieved.…”

“…The weight gained of CRWR coated with carbonaceous-SAPs can be respected to pores that allow the water to diffuse in and occupy the space. The presence of this pores able to increase the water uptake by the fertilizer and converted it into swollen substance before diffusion taken place [19].…”

Pyrolysis of carbonaceous particles and properties of Carbonaceous-g-Poly (acrylic acid-co-acrylamide) superabsorbent polymer for agricultural applications

“…MBA acts as a crosslinker agent was added in the monomer solution and was stirred at room temperature until the MBA was completely dissolved. The flask then was immersed in a water bath and heated up to 70 ºC and then APS initiator was added to the solution that was magnetically stirred at 300 rpm [13]. The reaction mixture was left to stir for 2 hours until gel point before the resulting hydrogel was removed from the reaction and dried overnight in oven at 60 ºC.…”