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The current study aims to use a facile and novel method to remove Congo red (CR) and Methyl Orange (MO) dyes from contaminated water with Maize offal biomass (MOB) and its nanocomposite with magnetic nanoparticles (MOB/MNPs). The MOB and MOB/MNPs were characterized with Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), BET, XRD and point of zero charge (pHPZC). The influence of initial CR and MO levels (20–320 mg/L), adsorbent dosage (1-3 g/L), pH (3-9), co-exiting ions, temperature (25–45 °C) and time (15–180 min) was estimated. The findings demonstrated that MOB/MNPs exhibited excellent adsorption of 114.75 and 29.0 mg/g for CR and MO dyes, respectively while MOB exhibited 81.35 and 23.02 mg/g adsorption for CR and MO dyes, respectively at optimum pH-5, and dose 2 g/L. Initially, there was rapid dye removal which slowed down until equilibrium was reached. The interfering/competing ions in contaminated water and elevated temperature favored the dyes sequestration. The MOB/MNPs exhibited tremendous reusability and stability. The dyes adsorption was spontaneous, and exothermic with enhanced randomness. The adsorption effects were well explained with Freundlich model, pseudo second order and Elovich models. It is concluded that MOB/MNPs showed excellent, eco-friendly, and cost-effective potential to decontaminate the water. Nanocomposite of Maize offal biomass demonstrated higher dyes removal. FTIR, SEM, BET, XRD and pHPZC provided vital evidence for dyes adsorption. MOB/MNPs displayed excellent stability and reusability for dyes adsorption. Groundwater samples exposed a higher dyes removal. Results were validated with equilibrium and kinetic adsorption models. [ABSTRACT FROM AUTHOR]

Water pollution is one of the major global challenges today. Water bodies are contaminated by the heavy release of waste effluents of textile industries, which includes intensively colored dye pollutants. Herein, a ternary nanocomposite of bismuth copper selenide with small particle size and ternary metal selenide (TMS)‐chitosan microspheres (TMS‐CM) of the spherical porous surface were successfully synthesized. SEM, XRD, EDX, FTIR, and UV/Vis spectrophotometry analysis revealed the structural and morphological characteristics of the newly synthesized nanocomposites. SEM imaging showed the average diameter of TMS nanoparticle to be 33 nm. The crystal size was calculated as 6.33 nm and crystalline structure as orthorhombic using XRD findings. EDX confirmed the presence of Bi, Cu, and Se in the ternary nanocomposite. The bandgap of 1.8 eV was calculated from Tauc's plot for the TMS nanocomposite. SEM confirmed the successful synthesis of spherical TMS‐CM microspheres of porous surface morphology with an average size of 885.6 μm. The presence of chitosan microspheres in the synthesis of TMS nanocomposite was identified by FTIR spectral analysis. Furthermore, highly efficient photocatalytic degradation (up to 95.4%) of ARS was achieved within 180 min at pH 4.0 using 0.5 g of TMS‐CM in sunlight. The first‐order kinetic model fitted well to the photocatalytic decontamination of ARS using TMS‐CM with a rate constant of 6.1x10−2 min−1. The TMS‐CM gave attractive results and high efficiency in photocatalytic degradation of ARS dye after reusing and regeneration of up to seven successive cycles. The newly synthesized nanophotocatalyst could be efficiently used for the decontamination of dye polluted water from textile industries. [ABSTRACT FROM AUTHOR]

Biosorpt ion of Mn (II) from aqueous solut ion by P. Ostreatus was invest igated at different concentrations, pH and temperature. The close agreement between the experimental and theoretical biosorption capacity confirmed that Pseudo 2nd order equat ion is best fitted to the present experimental data. The biosorption capacity of P. Ost reatus was observed to be dependent upon the pH and temperature of adsorpt ion system. The values of biosorpt ion maxima (Xm) and binding energy constant (Kb) were observed to decrease with rise in temperature in the range of 298 - 323K. The negative values of ΔG and ΔH showed the process of Mn (II) biosorpt ion onto P. Ost reatus is spontaneous and exothermic respectively. Similarly, the values of isosteric heat of biosorption (ΔD) were decreased with increase in surface coverage (e) which indicated that the surface of the P. Ostreatus is energet ically heterogeneous in nature. [ABSTRACT FROM AUTHOR]