| Title: | The effect of KOH activation and Ag nanoparticle incorporation on rice husk-based porous materials for wastewater treatment |
| Author(s): | Hossain N; Nizamuddin S; Selvakannan P; Griffin G; Madapusi S; Shah K; |
| Address: | "School of Engineering, RMIT University, Melbourne, VIC, 3001, Australia. Electronic address: bristy808.nh@gmail.com. School of Engineering, RMIT University, Melbourne, VIC, 3001, Australia. School of Science, RMIT University, Melbourne, VIC, 3001, Australia. School of Engineering, RMIT University, Melbourne, VIC, 3001, Australia; Birla Institute of Technology and Science, Pilani, Dubai Campus, Dubai International Academic City, P.O. Box No. - 345055, Dubai, United Arab Emirates" |
| DOI: | 10.1016/j.chemosphere.2021.132760 |
| ISSN/ISBN: | 1879-1298 (Electronic) 0045-6535 (Linking) |
| Abstract: | "Major agricultural solid waste, rice husk (RH)-based mesoporous materials were prepared by potassium hydroxide (KOH) treatment of RH and RH hydrochar (RHH) produced at 180 degrees C with 20 min reaction time. In this study, RH was treated with three different methods: RH activation by KOH (KOH-RH), RH activation by KOH-aqueous silver (Ag)-shell nanoparticle (AgNP) incorporation followed calcination at 550 degrees C for 2 h (AgNP-KOH-RH) and hydrothermally carbonized RH activation by KOH (KOH-RHH). The main objective of this study was to determine the effect of KOH activation with different synthesis approaches and compare the characterization results of RH based porous material to identify the potential adsorbent application for wastewater treatment. Therefore, after activation in different methods, all interactive properties such as elemental, chemical, structural, morphological, and thermal analyses were investigated comprehensively for all samples. The crystallinity peak intensity around 22 degrees lambda at the angle of diffraction of 2theta confirmed the presence of silica, higher stability of the material, and removal of organic components during the KOH activation. AgNP-KOH-RH and KOH-RHH presented high porosity on the outer surface. The presence of negligible volatile matter in KOH-RHH by TGA demonstrated the decomposition of organic compound. Very high ratio of aromatic carbon and lignin content by FTIR and XPS analysis in both AgNP-KOH-RH and KOH-RHH showed these two samples have improved stability. Very high negative surface charge (zeta potential) in AgNP-KOH-RH (-43.9 mV) and KOH-RHH (-43.1 mV) indicated the enhanced water holding capacity. Surface area for all experimented porous materials has been enhanced after KOH activation, where KOH-RHH demonstrated the maximum surface area value, 27.87 m(2)/g. However, AgNP-KOH-RH presented maximum pore diameter, 18.16 nm, and pore volume, 0.12 cm(3)/g. Hence, it can be concluded that both KOH-RHH and AgNP-KOH-RH have the potential to be implemented as wastewater adsorbents" |
| Keywords: | Hydroxides *Metal Nanoparticles *Oryza Porosity Potassium Compounds Silver *Water Purification AgNP modified rice husk Calcination Hydrochar KOH activation Porous materials; |
| Notes: | "MedlineHossain, Nazia Nizamuddin, Sabzoi Selvakannan, Periasamy Griffin, Gregory Madapusi, Srinivasan Shah, Kalpit eng England 2021/11/07 Chemosphere. 2022 Mar; 291(Pt 3):132760. doi: 10.1016/j.chemosphere.2021.132760. Epub 2021 Nov 2" |
