Zeolitic bagasse fly ash as a low-cost sorbent for the sequestration of p-nitrophenol: equilibrium, kinetics, and column studies.
OBJECTIVE
The purpose of the research is to investigate the application of bagasse fly ash, a sugar industry solid waste for the synthesis of zeolites and their behavior for the sorption of p-nitrophenol (p-NP).


METHODS
Zeolitic materials were prepared from bagasse fly ash using alkaline hydrothermal (CZBFA) and fusion (FZBFA) treatment. Comparative batch sorption studies of prepared zeolitic material and virgin material were undertaken to determine their capacities for removal of p-nitrophenol.


RESULTS
PXRD patterns revealed that zeolite P and analcime were the dominant contents of synthesized zeolitic material. Chemical composition, morphology, and crystalline nature of CZBFA and FZBFA were characterized by XRF, FTIR, and SEM. The Langmuir, Freundlich, Dubinin Redushkwich, and Temkin sorption isotherms were applied to compare the sorption nature and capacity of synthesized CZBFA and FZBFA with virgin BFA. For each sorbent-p-NP system, a pseudo-second-order kinetic model described the sorption kinetics accurately. The thermodynamics of the p-NP-sorbent systems exhibit an exothermic sorption process. Intraparticle diffusion model shows that the sorption rate was controlled by film diffusion followed by pore diffusion. Regeneration of sorbents was carried out by desorption studies with HCl, NaOH, and SDS detergent. The column studies were performed for the practical utility of sorbents, and breakthrough curve were obtained, which exhibit higher sorption capacity than batch method.


CONCLUSIONS
The sorption capacities of the synthesized zeolites had improved sorption capacities for the sequestration of p-NP and can be utilized as low-cost sorbents for treatment of p-nitrophenolic wastewater.
Department of Chemistry, Veer Narmad South Gujarat University, Surat 395007, Gujarat, India. bhavna606@gmail.com
Bhavna
B
Shah
Ritesh
R
Tailor
Ajay
A
Shah
D000327:Adsorption; D000383:Agriculture; D060729:Coal Ash / Q000737:chemistry*; D004058:Diffusion; D007220:Industrial Waste / Q000517:prevention & control; D007700:Kinetics; D059625:Liquid-Liquid Extraction; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D009596:Nitrophenols / Q000737:chemistry*; D033362:Powder Diffraction; D031786:Saccharum / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D014961:X-Ray Diffraction; D017641:Zeolites / Q000737:chemistry*
D060729:Coal Ash; D007220:Industrial Waste; D009596:Nitrophenols; D014874:Water Pollutants, Chemical; D017641:Zeolites; C024836:4-nitrophenol