Hamidi, R. M., Siyal, A. A., Luukkonen, T., Shamsuddin, R. M., & Moniruzzaman, M. (2022). Fly ash geopolymer as a coating material for controlled-release fertilizer based on granulated urea. RSC Advances, 12(51), 33187–33199. https://doi.org/10.1039/D2RA06056F
Fly ash geopolymer as a coating material for controlled-release fertilizer based on granulated urea
|Author:||Hamidi, Rashidah Mohamed1; Siyal, Ahmer Ali1; Luukkonen, Tero2;|
1HICoE, Centre for Biofuel and Biochemical Research (CBBR), Institute of Self-sustainable Building, Department of Chemical Engineering, Universiti Teknologi PETRONAS, 32610 Bandar Seri Iskandar, Perak Darul Ridzuan, Malaysia
2University of Oulu, Fibre and Particle Engineering Research Unit, P.O. Box 8000, Finland
3Centre of Research in Ionic Liquids (CORIL), Institute of Contaminant Management, Department of Chemical Engineering, Universiti Teknologi PETRONAS, 32610 Bandar Seri Iskandar, Perak Darul Ridzuan, Malaysia
|Online Access:||PDF Full Text (PDF, 8.3 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2022112466735
Royal Society of Chemistry,
|Publish Date:|| 2022-11-24
Nitrogen loss from urea fertiliser due to its high solubility characteristics has led to the invention of controlled release urea (CRU). Majority of existing CRU coatings are produced from a non-biodegradable, toxic and expensive synthetic polymers. This study determines the feasibility of fly ash-based geopolymer as a coating material for urea fertilizer. The effects of fly ash particle size (15.2 μm, 12.0 μm, and 8.6 μm) and solid to liquid (S : L) ratio (3 : 1, 2.8 : 1, 2.6 : 1, 2.4 : 1 and 2.2 : 1) on the geopolymer coating, the characterization such as FTIR analysis, XRD analysis, surface area and pore size analysis, setting time analysis, coating thickness, and crushing strength, and the release kinetics of geopolymer coated urea in water and soil were determined. Lower S : L ratio was beneficial in terms of workability, but it had an adverse impact on geopolymer properties where it increased porosity and decreased mechanical strength to an undesirable level for the CRU application. Geopolymer coated urea prepared from the finest fly ash fraction and lowest S : L ratio demonstrated high mechanical strength and slower urea release profile. Complete urea release was obtained in 132 minutes in water and 15 days in soil from geopolymer-coated urea whereas for uncoated urea it took only 20 minutes in water and 3 days in soil. Thus, geopolymer can potentially be used as a coating material for urea fertilizer to replace commonly used expensive and biodegradable polymer-based coatings.
|Pages:||33187 - 33199|
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
215 Chemical engineering
216 Materials engineering
218 Environmental engineering
We would like to acknowledge the supports from Ministry of Higher Education (MOHE) Malaysia through HICoE Grant (cost centre 015MA0-052/015MA0-104/015MA0-136) to Centre for Biofuel and Biochemical Research (CBBR).
© 2022 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.