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In the present investigation, a novel, green, and economical dual-functionalized pullulan/kaolin hydrogel nanocomposite (f-PKHN) was fabricated and subsequently applied for the liquid-phase decontamination of paracetamol (PCT), a pharmaceutical pollutant. Pullulan and kaolin were functionalized with L-asparagine and gallic acid, respectively. The physicochemical facets of the functionalized pullulan/kaolin hydrogel nanocomposite and its interactive behavior with PCT were elucidated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), and elemental mapping. The process parameters along with the isotherm, kinetics, and thermodynamics were methodically appraised via a batch technique to unveil the adsorption performance of the as-fabricated hydrogel nanocomposite. The adsorption isotherm and kinetics of PCT uptake by f-PKHN conform well to Freundlich and pseudosecond-order models, respectively. Relying on hydrogen bonding, n−π, and van der Waals interactions, the maximum adsorption capacity was 332.54 mg g −1 , higher than for most of the previous adsorbents reported in the literature for PCT removal. Thermodynamic calculations corroborated endothermic, spontaneous, and feasible adsorption phenomena. The maintenance of a high uptake percentage (69.11%) in the fifth consecutive adsorption−desorption cycle implied the significant reusable potential of f-PKHN. Swelling studies exhibited 90% swelling within 200 min, indicating the successful fabrication of a cross-linked hydrogel network. The real water (distilled water, tap water, and river water) samples spiked with PCT specified a significant uptake of PCT (>85%), and the minor influence of ionic strength on the adsorptive potential of f-PKHN validated its potentiality for the decontamination of real effluents. In conclusion, f-PKHN with substantial adsorption capacity, green characteristics, and excellent reusability can be reckoned with as a promising adsorbent for the de-escalation of PCT from aquatic sources as well as at the industrial level.

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NiFe 2 O 4 /polythiophene nanocomposite was synthesized by in situ chemical oxidative polymerization of thiophene in NiFe 2 O 4 nanoparticles presence, whereas NiFe 2 O 4 nanoparticles were prepared via coprecipitation method. Fourier transform infrared (FTIR), X-ray diffraction (XRD), UV-Visible, and SEM, EDX techniques were used for characterization of the nanocomposite. The effect of various parameters such as adsorbent dose, contact time, initial dye concentration, and initial pH of solution on the adsorption of Janus green B (JG) and Fuchsin basic (FB) onto the nanocomposite was optimized by batch studies. The equilibrium uptake data ascribed well to the Langmuir model with maximum adsorption capacity of 143 and 498 mg/g at 303 K for JG and FB, respectively. The exceptional high adsorption capacity of NiFe 2 O 4 /polythiophene nanocomposite for JG and FB was ascribed to π-π and electrostatic interactions. Kinetics studies pointed out that JG and FB removal followed pseudo-second order model. The negative values of ΔH (JG: -47.28; FB: −38.00 kJ/ mol) and ΔG (JG: −9.347 to −6.442; FB: −14.16 to -12.85 kJ/mol) pointed out the feasibility, spontaneity, and exothermic nature of removal process. Negative value of ΔS (JG: -0.125; FB: -0.078 kJ/mol) suggested decrease in randomness at the solid/ liquid interface. The results showed that NiFe 2 O 4 /polythiophene is an appealing adsorbent for the uptake of JG and FB dyes from aquatic environment. K E Y W O R D S adsorption, Fuchsin basic, Janus green B, NiFe 2 O 4 /polythiophene nanocomposite, non-linear regression analyses, thermodynamics