Wastewater treatment is of utmost importance in providing equitable and safe drinking water to all. In that bid, herein, a novel and potential Alginate-Silver nanoparticle/Mica (Alg-AgNPs/MC) bio-nanocomposite has been synthesized by the green method. The synthesized nanocomposite was further harnessed for the removal of methylene blue (MB) and brilliant green (BG) dyes from an aqueous solution for the first time and has not been reported in literature till now. The Alg-AgNPs/MC bionanocomposite was thoroughly characterized through FTIR, SEM-EDX, TEM, XRD, and TGA/DTA analysis. Moreover, AlgAgNPs/MC bionanocomposite was further employed to remove both dyes from the aqueous solution in batch mode. The Alg-AgNPs/MC bionanocomposite could remove 99.07% of MB and 91.53% of BG at an initial concentration of (20 mg L-1), adsorbent dosage (0.01 g), time (180 min), pH-8 for MB dye and pH-9 for BG. The Alg-AgNPs/MC bionanocomposite achieved maximum adsorption capacities of 352 and 249 mg g-1 for BG and MB dyes, respectively. The equilibrium adsorption data for both dyes were best fitted to the Freundlich model with R2, 0.9945 and 0.9799 for BG and MB dyes, respectively. The adsorption dynamics were best followed by a pseudo second order kinetic model for both dyes. The positive value of thermodynamic parameter & UDelta;H indicates the process to endothermic and spontaneous in nature. The exhausted Alg-AgNPs/MC bionanocomposite can be regenerated up to the 4th cycle successfully.& COPY; 2023 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.

Crystal violet (CV) a cationic dye is more harmful than anionic dye. CV is employed in many industries, including leather, paper, pharmaceutical, textile, and cosmetics. It causes several harmful effects like eye and skin irritation; in extreme situations, it causes renal and kidney or respiratory failure. Because it is non-biodegradable, this dye sticks to the aquatic environment for a very long period. Therefore, it is important to remove this dye from wastewater to prevent its contamination to normal water bodies. This study evaluated the performance of Chitosan-modified L-cysteine/Bentonite (CS-Cys/Bent) bionanocomposite for the adsorption of CV dye. To investigate the surface morphology and potential interaction between the (CS-Cys/Bent) bionanocomposite and CV dye, the (CS-Cys/Bent) were characterized by TEM, SEM-EDX, FTIR and XRD techniques. At pH-8, with 0.01 g of adsorbent dosage, and an optimal duration of 180 min, the maximum adsorption capacity (85.13 mg/g) was observed. The maximum adsorption capacity was 219, 237, and 240 mg/g at 303, 313 and 323 K. The experimental data were subsequently examined using a variety of isotherm models; with the highest R2 values (0.990, 0.983 and 0.984 at 303, 313 and 323 K, respectively), the Freundlich model was the best fitted model. Among the kinetics models, pseudo-second order (PSO) was the best-described kinetic model with the highest coefficient (R2, 0.999). The positive values of Delta S degrees (0.037 kJ/mol.K) and Delta H degrees (7.148 kJ/mol) demonstrated the process to be spontaneous and endothermic. The (CS-Cys/Bent) can be successfully recycled up to the fourth cycle.

Wastewater treatment is of utmost importance in providing all equitable and safe drinking water. In that bid, herein, a novel Alginate@Silver nanoparticle-Mica (Alg@AgNPs-MC) bionanocomposite has been synthesized for the removal of methylene blue (MB)and brilliant green (BG) dyes from an aqueous solution. The physicochemical properties of (Alg@AgNPs-MC) bionanocomposite were thoroughly characterized through FTIR, SEM-EDX, TEM, XRD, and TGA/DTA analysis. Moreover, (Alg@AgNPs-MC) bionanocomposite was further employed to remove both the dyes from the aqueous solution in batch mode. Prominent factors affecting the adsorption of the dyes were optimized by one factor at a time approach. The (Alg@AgNPs-MC) bionanocomposite could remove 99.07% of MB and 91.53% of BG from the aqueous solution at an initial concentration of (20 mg L -1 ), adsorbent dosage (0.01 g), time (180 min), pH 8 for MB dye and pH 9 for BG. The (Alg@AgNPs-MC) bionanocomposite achieved maximum adsorption capacities of 352 and 249 mg g -1 for BG and MB dyes, respectively. The equilibrium adsorption data for both the dyes were best fitted to the Freundlich model with (R 2 , 0.9945 and 0.9799 for BG and MB dyes, respectively), indicating the heterogeneous nature of (Alg@AgNPs-MC) bionanocomposite. The adsorption dynamics were best followed by a Pseudo second order kinetic model with a correlation coefficient of (R 2 , 0.975 and 0.9815 for BG and MB dyes, respectively) for both the dyes. The breakthrough capacity, obtained in dynamic mode, was found to be 60 and 100 mg g -1 , while the exhaustive capacities were determined to be 210 and 310 mg g -1 for MB and BG, respectively. The (Alg@AgNPs-MC) bionanocomposite can be regenerated up to the 4 th cycle successfully.

Herein, we have reported the synthesis of a potential bentonite/silver nanoparticles-Alginate (Bent/AgNPs-Alg) bio-nanocomposite and its possible application to adsorb methylene blue (MB) dye from an aqueous solution. Different analytical methods, such as SEM–EDX, TEM, FTIR, and XRD, were used to analyze the surface morphology of the bio-nanocomposite. The specific surface area of (Bent/Ag-Alg) bio-nanocomposite based on monolayer coverage was found to be 562.66 m 2 .g −1 . The maximum adsorption was observed at the optimum condition (equilibrium time 180 min, adsorbent dose 0.5 g.L −1 , pH 8 and initial concentration 100 mg.L −1 ). The Langmuir isotherm best fits the experimental data, with the highest correlation coefficient constant ( R 2 ) 0.986, 0.989 and 0.973 at 303, 313 and 323 K, respectively. The maximum monolayer adsorption capacity ( q max ) was recorded as 242.56 mg.g −1 . Based on the highest correlation coefficient ( R 2 ) 0.961, 0.943, and 0.975 at 50, 100, and 150 mg.L −1 , respectively, pseudo-second-order kinetics best obeyed the experimental data. The positive value of ΔHº (54.828 kJ.mol −1 ) and ΔSº (0.215 kJ.mol −1 .K −1 ) confirmed that the adsorption was endothermic and spontaneous. The breakthrough and exhaustion capacity was observed at 200.00 and 680.00 mg.g −1 , respectively. 0.1 N HCl solution was used for desorption of the adsorbed MB dye. The spent adsorbent can be regenerated successfully up to the 6th cycle. Therefore, Bent/AgNPs-Alg bio-nanocomposite could be harnessed as a potential adsorbent to remove hazardous MB dye from the wastewater.

Herein, poly(acrylamide)-grafted cell@Fe 3 O 4 (PAC@Fe 3 O 4 ) nanocomposite was synthesized through the polymerization process of acrylamide polymers oxidative available radical in the existence of cell@Fe 3 O 4 nanomaterial nanoparticles. Various analytical methods including FTIR, SEM, XRD, and TEM were used to characterize the material. The nanocomposite material was studied further for its ability to adsorbed Pb(II), Ni(II), and Cu(II) from wastewater. To optimize adsorption process, the impact of different factors like contact time, temperature, pH, doses, and concentration was performed. Adsorption of metal ion is pH-dependent, with the highest removal efficiency occurring at high pH levels and at pH value 5; the maximum capacities of the chosen metal ions were determined for Pb(II) and Cu(II) while pH 4 for Ni(II). The maximum capacity ( q m ) was observed to be 313.02 mg g −1 for Pb(II), 219.33 mg g −1 for Ni(II), and 210.71 mg g −1 for Cu(II), respectively. The kinetic parameters indicate that the metal ion adsorption by PAC@Fe 3 O 4 followed second-order kinetics, with chemical adsorption as the rate-limiting step. The nature of adsorption was endothermic and spontaneous demonstrated by positive Δ H ° and negative Δ G ° values.

Herein, we report the synthesis of a novel bio-nanocomposite (Alg-Cst/Kal) for the effective removal of the dye "Crystal Violet" from its aqueous solutions. In order to observe the surface morphology and functional groups, the bio-nanocomposite was characterized using various techniques such as SEM, EDX, TEM, FTIR, XRD, and TGA. The effect of parameters like contact time, pH, concentration and temperature on the adsorption of the dye over adsorbent has been studied in detail. The dye - adsorbent system has been tested over various isotherm models and found to follow the Freundlich adsorption isotherm model at 303 K. The developed bio-nanocomposite material exhibits an excellent adsorption toward Crystal Violet with a maximum adsorption capacity of 169.49 mg.g(-1). The experimental data has been further validated by applying various kinetic models and the pseudo-second order kinetic model was the best suited model. The calculated rate constant values ranged from 0.0046 to 0.0204 g.mg(-1).min(-1) for different dye concentrations. The positive values of change in enthalpy, Delta H degrees (9.765 kJ.mol(-1)) and change in entropy, Delta S degrees (0.0565 kJ.mol(-1).K-1) obtained through thermodynamic studies demonstrate the endothermic nature and spontaneity of the adsorption process, respectively. The adsorption capacity of the adsorbent for the removal of the Crystal Violet dye was also compared with other adsorbents and found maximum. Novelty statement A novel bio-nanocomposite is synthesized by modifying the biopolymer alginate, cysteine and mixing the clay, kaolinite (Kal). The adsorption abilities of the material was tested the on the cationic hazardous dye, Crystal Violet. The material is novel and no attempt has so far been made to examine its batch adsorption abilities to remove hazardous dyes from the wastewater. The results are highly encouraging as out of all the adsorbents tested so far highest adsorption of the dye is observed in the present studies.