Turning date palm waste into carbon nanodots and nano zerovalent iron composites for excellent removal of methylthioninium chloride from water

Abstract Novel carbon nanodots (nCD-DBC) and nano zero-valent iron composites (nZVI-DBC) were synthesized using date palm waste-derived biochar (DBC). The synthesized materials were analyzed for chemical and structural composition by using FTIR, SEM, XRD, and TGA, and evaluated for their methylthioninium chloride dye (MB) removal efficiency from contaminated aqueous solutions. pH 7.0 was found optimum for the highest MB removal in sorption batch studies. Kinetics sorption of MB onto the sorbents was best described by pseudo-second-order (R2 = 0.93–0.99) and Elovich models (R2 = 0.86–0.97) implying that sorption was being controlled by chemisorption. Langmuir model predicted maximum sorption capacities for nCD-DBC, nZVI-DBC, and DBC were 1558.66, 1182.90, and 851.67 mg g−1, respectively, which correlated with the results of kinetics sorption. Likewise, nCD-DBC yielded the highest partition coefficient (7067 mL g−1), followed by nZVI-DBC (1460 mL g−1), and DBC (930 mL g−1). Post-sorption XRD, FTIR, and SEM analyses depicted the binding of MB onto the sorbents. It was suggested that electrostatic interactions, π–π electron donor-accepter interactions, degradation, and diffusion were responsible for MB removal by the synthesized materials. Therefore, the nCD-DBC, nZVI-DBC, and DBC can potentially be used for scavenging MB dye from contaminated aqueous solutions.

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The effect of pyrolysis temperature and feedstock on date palm waste derived biochar to remove single and multi-metals in aqueous solutions

Sustainable Environment Research ◽

10.1186/s42834-021-00083-x ◽

2021 ◽

Vol 31 (1) ◽

Author(s):

Banu Sizirici ◽

Yohanna Haile Fseha ◽

Ibrahim Yildiz ◽

Thomas Delclos ◽

Abbas Khaleel

Keyword(s):

Aqueous Solutions ◽

Date Palm ◽

Pyrolysis Temperature ◽

Total Carbon ◽

Spectroscopic Techniques ◽

Total Carbon Content ◽

X Ray ◽

Date Palm Waste ◽

Palm Waste ◽

Palm Leaf

AbstractIn this study, leaf and frond date palm waste as feedstock was used to derive biochars. The effects of pyrolysis temperatures on their physical and chemical properties, and their capacity to remove copper, iron, nickel and zinc from single and multi-metal solutions at various pH values were investigated. Analytical and spectroscopic techniques such as scanning electron microscopy, energy dispersive X-ray, Fourier transform infrared spectroscopy, X-ray diffraction, carbon, hydrogen, nitrogen, sulfur elemental analysis, Brunauer Emmett Teller analysis were conducted for characterization. The pore volume, surface area, pH, and total carbon content of date palm leaf and frond biochar increased while functional groups and hydrogen, nitrogen and oxygen content of biochar decreased with increasing pyrolysis temperature compared to feedstock. The removal efficiencies and sorption capacity for single and mixed metal ions were found between 98 and close to 100% and 2.4 and 3.0 mg g− 1 by leaf and frond biochar samples at pH > 6, respectively. Biochar obtained from different feedstock at different pyrolysis temperature did not show any statistically significant improvements on the removal of single or mixed metals from aqueous solutions. The date palm leaf or frond biochar obtained at low pyrolysis temperature is as effective to remove metals as the ones obtained at high pyrolysis temperatures. Therefore, to consume less energy to produce biochar at lower temperature which exhibits same effective removal efficiency will be a win-win solution in terms of sustainability and economy. As a result, date palm waste biochar can be effectively used to remove metals in water and wastewater.

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