Sustainable robust green synthesis of nanoparticles from waste aquatic plants and its application in environmental remediation.

Green synthesis of nanoparticles using natural materials is an emerging technique that fascinates the scientific community globally for the treatment of wastewater. In the present study, aquatic plants such as Piaropus crassipes (PC) and Lemna gibba (LG), were utilized to make low-cost nanoparticles, and its feasibility for the removal of Zn(II) ions was studied. The synthesized nano adsorbents were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, Brunauer-Emmett-Teller analysis, and zeta potential analysis. The optimal conditions were evaluated by batch adsorption studies, to investigate the parameters such as pH (2-7), adsorbent dosage (0.5-5 g/L), initial concentration (20-60 mg/L), and contact time (10-120 min) etc. The isotherm, and kinetic data results fit well with Langmuir, and pseudo-second order models. The anticipated monolayer adsorption capacity with respect to the PC, and LG was found to be 42.41 mg/g and 27.65 mg/g, respectively. Thermodynamic studies showed that the process is exothermic. The adsorption mechanism of PC/LG on Zn(II) exhibited surface complexation, ion exchange, and diffusion. Desorption studies were performed to analyze the recovery potential of Zn(II) ion. Hence, this article investigates the economic synthesis of green nanoparticles, and their potential utilization in heavy metal remediation.

Synthesis and characterization of GO/FeSO4 composites for the effective removal of Hg2+ and Cd2+ ions from the synthetic effluent.

Heavy metals like Cd and Hg removal using novel graphene oxide/ferrous sulfate (GO/FeSO4) was taken for experimental studies and analysis. In this work, GO/ FeSO4 was synthesized by both modified Hummer's and chemical precipitation method. The synthesized composite was characterized by field emission scanning electron microscope (FESEM), Fourier transform infrared (FTIR) spectroscopy, and Raman spectroscopy for their properties. Brunauer Emmett-Teller (BET) analysis was characterized for the surface analysis of the prepared nanocomposites. FESEM images exhibit flake-like structures in surface morphological studies. FTIR peaks confirmed the presence of carboxyl groups in GO. Raman spectroscopy intensity peak [ID/IG ratio1.18] confirmed the synthesized sample was GO. The experimental parameters such as initial concentration, pH, and adsorbent dosage were optimized to achieve maximum heavy metal removal efficiency. The influence of initial heavy metal concentration (0.2-1 mg/L), pH of solution (pH 3-7), and adsorbent dosage (1-5 g/L) was studied and reported. Adsorption kinetic studies were performed and the process was found to fit well with pseudo-second-order kinetics.

Enhanced adsorption of Cr(VI), Ni(II) ions from aqueous solution using modified Eichhornia crassipes and Lemna minor.

The environment is seriously affected by the release of hazardous heavy metals from the industries. The transformation of aquatic weeds into valuable nanosorbent has been considered as effective and efficient material in the wastewater treatment process. The aim of the study is to analyze the potential of nano-EC and nano-LM for the removal of chromium(VI) and nickel(II) ions. The characteristics of nanosorbent were analyzed using Fourier transform infrared spectroscopy (FTIR), Brunauer Emmett-Teller analysis (BET), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), and thermo gravimetric analysis (TGA), respectively. Adsorptive performance of nanosorbent was studied with respect to pH, contact time, nano adsorbent dosage, and metal ion concentration. The maximum monolayer adsorption capacity of Cr(VI) and Ni(II) with respect to nano-EC was found to be 79.04 mgg-1 and 85.09 mgg-1, respectively. Adsorption isotherm and kinetic studies were performed and it was reported that adsorption isotherm follows Langmuir model with regression coefficient R2 > 0.9 for nano-EC and nano-LM respectively. The pseudo-second order model was found to fit well with experimental data. Experimental results suggested that nano-EC can be considered as a suitable nanosorbent for the removal of Cr(VI) and Ni(II) ions from effluents.