Abstract
Globally, organic dyes are major constituents in wastewater effluents due to their large-scale industrial applications. These persistent pollutants adversely impact the public health of different living entities. Thus, wastewater remediation has become an indispensable necessity. Herein, we greenly synthesized iron oxide nanoparticles (SP-IONPs) using Spirulina platensis microalgae to remove cationic crystal violet (CV) and anionic methyl orange (MO) dyes from their aqueous solution. The engineered sorbent was thoroughly scrutinized by different characterization techniques of FT-IR, BET surface area, SEM, EDX, TEM, VSM, UV/Vis spectroscopy, and pHPZC measurement. The proficiency of SP-IONPs was methodically appraised for its sorptive performance towards the target CV and MO dyes under variable technological parameters (batch scenario). Collectively, the outlined results inferred an amazing efficacy characterized to the SP-IONPs sorbent for the expulsion of relevant dyes from the aqueous media. Regarding the dynamic static sorption data, the kinetics profile was ascribed to the pseudo-second order model, whereas sorption isotherm was quantitatively dominated by the Langmuir theory with maximum sorption capacities of 256.4 mg g-1 and 270.2 mg g-1 for CV and MO, respectively. Thermodynamics findings conformed the endothermic nature of sorption process. Repeatability of the spent sorbent was successfully emphasized for 5 times of sorption/desorption cycles. The productive sorbent admirably sequestered CV and MO dyes from spiked tap water. The potency of SP-IONPs as color collecting material from real dyeing effluents was achieved.
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All data generated or analyzed during this study were included in the submitted article. In addition, the datasets used or analyzed during the current study were available from the corresponding author on reasonable request.
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Acknowledgements
This work was performed at Faculty of Science, Port-Said University, Port-Said, Egypt. The authors; therefore, acknowledge with thanks the University technical support. Also, the authors would like to thank Prof. Dr. Khaild Zaki Elwakeel, professor of Environmental Chemistry, Environmental Science Department, Faculty of Science, Port Said University, Egypt, for his cooperation and helpful guidance in preparing the revised version.
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Shymaa M. Shalaby: conceptualization, methodology, investigation, and writing original draft.
Fedekar F. Madkour: conceptualization, methodology, and investigation.
Hala Y El-Kassas: conceptualization, methodology, and investigation.
Adel A. Mohamed: conceptualization, methodology, and investigation.
Ahmed M. Elgarahy: conceptualization, investigation, data curation, writing, reviewing, and editing.
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Highlights
•Green synthesis of iron oxide nanoparticles for efficient sorption of crystal violet (CV) and methyl orange (MO) dyes.
•Maximum sorption capacity close to 256.4 mg g-1 and 270.2 mg g-1 for CV and MO, respectively, fitted by Langmuir equation.
•Fast kinetics (equilibrium~60 min), fitted by pseudo-second order kinetics model.
•Efficient modeling of thermodynamics parameters (endothermic nature).
•Sorbent stability over 5 sorption/desorption cycles; poorly affected by system complexity (good efficiency in tap water and industrial wastewater).
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Shalaby, .M., Madkour, F.F., El-Kassas, H.Y. et al. Green synthesis of recyclable iron oxide nanoparticles using Spirulina platensis microalgae for adsorptive removal of cationic and anionic dyes. Environ Sci Pollut Res 28, 65549–65572 (2021). https://doi.org/10.1007/s11356-021-15544-4
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DOI: https://doi.org/10.1007/s11356-021-15544-4