Parametric Study on the Adosroption of Urea on Montmorillonite
Author : Almarines, Robert Louise Zapanta
Major Adviser : Bautista, Ramer P.
Major Co-Adviser : Fernando, Lilia M.
Committee Members : Arocena, Rhebner E.; Detras, Monet Concepcion M.; Migo, Veronica P.
Year : 2018
Month : June
Type : Thesis
This manuscript can be accessed: Only after the consultation with author or adviser
In this study, a urea-montmorillonite fertilizer composite was prepared by the adsorption of urea onto the montmorillonite surfaces. Prior to the preparation, the montmorillonite sample was characterized to determine its viability as a carrier for urea while the urea was characterized so as to compare it with the urea-montmorillonite fertilizer and confirm adsorption interactions. Using a 2³ full factorial design, the effect of the parameters, urea-nanoclay ratio, mixing time, and mixing temperature on the urea concentration of the fertilizer sample was determined. An analysis of variance revealed urea-nanoclay ratio to be the sole significant parameter wherein an increase in the ratio led to an increase in the urea concentration. On the other hand, a significant curvature effect indicated that an optimum urea-concentration can be found within the values used for the urea-nanoclay ratio. Characterization of the urea-montmorillonite fertilizer in terms of appearance and morphology showed possible intercalation of urea into the galleries of montmorillonite alongside possible urea crystallization on the outer surface. In terms of bond formations, shifts in N-H and C=O bond vibrations to lower frequencies indicate the intermolecular hydrogen bonding between urea and montmorillonite and thus, confirm urea adsorption. Likewise, urea-montmorillonite interaction was also confirmed in terms of thermal stability by the reduced crystallinity of urea in the composite.
Go back to Research Abstracts