Use of macadamia nut shell residues as magnetic nanosorbents

Wongcharee, Surachai and Aravinthan, Vasantha and Erdei, Laszlo and Sanongraj, Wipada (2017) Use of macadamia nut shell residues as magnetic nanosorbents. International Biodeterioration and Biodegradation, 124. pp. 276-287. ISSN 0964-8305


Abstract

Nanosorbents have been increasingly used for targeted contaminant removal; however, handling and separation of spent sorbents from treated water remains a challenge. To address these drawbacks, a hybrid magnetic nanosorbent was prepared from waste macadamia nut shell and magnetite nanoparticles. The novel nanosorbent had primarily meso- and macroporous structure with 70 m2 g−1 specific surface area. Batch sorption tests using methylene blue model pollutant found sorption capacities increasing from 33 to 42 mg g−1 with temperature in the 25–45 °C range. Nonlinear regression analyses found that process kinetics was accurately described by a fractal-like pseudo first order model. The isotherms showed excellent fits to the Langmuir model and implied monolayer adsorption mechanism. The thermodynamic parameters confirmed that the process was spontaneous, endothermic, and involved physisorption. The point of zero charge was 7.4, which is advantageous in the removal of anionic aquatic pollutants. The ferrimagnetic sorbent had 48 emu g−1 saturation and 0.65 emu g−1 remanence that allowed easy handling and rapid separation by magnetic field. Spent sorbents were effectively regenerated by acidic wash for subsequent reuse over four cycles. The intrinsic characteristics of the magnetite/carbon nanosorbent befit tailored water and wastewater treatment applications.


Statistics for USQ ePrint 32219
Statistics for this ePrint Item
Item Type: Article (Commonwealth Reporting Category C)
Refereed: Yes
Item Status: Live Archive
Faculty/School / Institute/Centre: Current - Faculty of Health, Engineering and Sciences - School of Civil Engineering and Surveying (1 Jul 2013 -)
Faculty/School / Institute/Centre: Current - Faculty of Health, Engineering and Sciences - School of Civil Engineering and Surveying (1 Jul 2013 -)
Date Deposited: 19 May 2017 04:47
Last Modified: 17 Mar 2021 01:04
Uncontrolled Keywords: magnetite, activated carbon, nanosorbent, adsorption, nonlinear regression
Fields of Research (2008): 03 Chemical Sciences > 0303 Macromolecular and Materials Chemistry > 030301 Chemical Characterisation of Materials
05 Environmental Sciences > 0502 Environmental Science and Management > 050205 Environmental Management
Identification Number or DOI: https://doi.org/10.1016/j.ibiod.2017.04.004
URI: http://eprints.usq.edu.au/id/eprint/32219

Actions (login required)

View Item Archive Repository Staff Only