Synthesis of Gd0.5Sr0.5FeO3 perovskite-type nanopowders for adsorptive removal of MB dye from water

Structural Analysis and Adsorption Studies of (PbO, MgO) Metal Oxide Nanocomposites for Efficient Methylene Blue Dye Removal from Water

In the present work, magnesium oxide (MgO) and lead oxide (PbO) nanoparticles were prepared by the co-precipitation method. Their structural parameters and morphology were investigated using XRD, HRTEM, and FTIR. The formation of the phases was seen to have small average crystallite sizes and an orthorhombic crystal structure for both MgO and PbO nanoparticles. The results of HR-TEM showed irregularly shaped nanoparticles: quasi-spherical or rod-like shapes and spherical-like shapes for MgO and PbO nanoparticles, respectively. The produced nanoparticles' size using X-ray diffraction analysis was found to be 17 nm and 41 nm for MgO and PbO nanoparticles, respectively. On the other hand, it was observed from the calculations that the optical band gap obeys an indirect allowed transition. The calculated values of the band gap were 4.52 and 4.28 eV for MgO and PbO NPs, respectively. The MB was extracted from the wastewater using the prepared composites via absorption. Using a variety of kinetic models, the adsorptions were examined. Out of all the particles, it was discovered that the composites were best. Furthermore, of the models currently under consideration, the pseudo-second-order model best fit the degradation mechanism. The resultant composites could be beneficial for degrading specific organic dyes for water purification, as well as applications needing a wider optical band gap.

Potassium permanganate dye removal from synthetic wastewater using a novel, low-cost adsorbent, modified from the powder of Foeniculum vulgare seeds

In this study, Seeds powder of Foeniculum vulgare was used to prepare a novel adsorbent, the modification of the prepared adsorbent was done by each of ZnCl₂, oxalic acid, and CuS, all samples have been characterized by different techniques and examined for Potassium permanganate (KMnO₄) adsorption. Among the four modified and unmodified adsorbents, the sample modified by oxalic acid has the highest percentage removal for KMnO₄ adsorption (%R = 89.36). The impact of KMnO₄ concentration, adsorbent dose, contact temperature, contact time, and solution pH on the adsorption performance was also investigated. The experimental data of this adsorption was analyzed by different kinetic and isotherm models. As Constants of thermodynamic ΔG°, ΔH°, and ΔS° have been also evaluated. Surface area, pore volume, and pore size of the modified oxalic acid F. vulgare seeds powder adsorbent were determined as 0.6806 m² g^-1, 0.00215 cm³ g^-1, and 522.063 Å, as pH_ZPC also was stated to be 7.2. The R² values obtained from applying different isotherm and kinetic models (0.999 and 0.996) showed that the adsorption performance of KMnO₄ follows the Langmuir and Pseudo 2nd order models. Furthermore, high adsorption capacities of 1111.11, 1250.00, and 1428.57 mg g^-1 were achieved at three temperatures that were used in this study. Constants of thermodynamic ΔG°, ΔH°, and ΔS° values indicate chemical and spontaneous adsorption at the adsorbent surface. Therefore, the modified adsorbent can be used to remove KMnO₄ dye from pollutant water samples.

Enhancement of the adsorptive performance of TiO2nanoparticles towards methylene blue by adding suspended nanoparticles of Pt: kinetics, isotherm, and thermodynamic studies

Methylene blue (MB) is one of the most dangerous dyes found in numerous industries' wastewaters. Thus, the effect of suspended Pt nanoparticles (NPs) on the adsorption capability of TiO₂NPs towards MB was investigated in this research. Factors affecting (adsorbate initial concentration, agitation time, solution pH, and temperature) the adsorption capacity of MB on the modified TiO₂NPs were also studied. It was found that the first two factors have a positive effect, the temperature has an adverse impact, and the maximum uptake was observed when pH is 11. Isotherm parameters of Langmuir, Freundlich, and Timken models were determined. Langmuir's model was found to be the best one for analyzing the experimental data. The adsorption capacities obtained were 100.61, 90.66, and 80.26 mg g^-1at 25 °C, 40 °C, and 55 °C, respectively. 1^storder, 2^ndorder, and intra-particle diffusion kinetic models were utilized to analyze experimental data. It found that these data were explained well by the 2^ndorder model, indicating that this adsorption is chemisorption. Thermodynamic parameters were also determined, and the results obtained suggest that this adsorption is an exothermic and spontaneous process. The findings show that TiO₂NPs modified by suspended Pt NPs will get a strong attraction in the treatment of fluids and wastewaters.

Wastewater Purification from Permanganate Ions by Sorption on the Ocimum basilicum Leaves Powder Modified by Zinc Chloride

The powder of Ocimum Basilicum leaves was treated by zinc chloride (ZnCl2) and applied as a new and low-cost sorbent for extraction of permanganate anions (MnO4−) from liquid phase. The functional groups of the ring stretching vibration, –NH2 deformation, stretching of C-O, stretching of CH, and stretching of –NH were found in the sorbent of zinc chloride Ocimum basilicum leaves powder (ZCOBLP) at 1516.21, 1629.33, 1047.00, 2929.88, and 3294.93 cm−1, respectively. This adsorbent has 8.3 pHZPC, 117.27 m2·g−1 surface area, 0.00711 cc·g−1 pore volume and average pore diameter of 264.144 Å. The outcomes of sorption experiments designate the positive impact for temperature, time of agitation, and started concentration of MnO4− and negative impact for pH. The optimal conditions were 1300 mg·L−1 as started adsorbate concentration, 55°C as solution temperature, agitation time of 420 min, and pH of 1.5. The outcomes of the equilibrium and dynamic approve that this sorption is spontaneous and heat-absorbing process, and the obtained data were described well by isotherm model of Langmuir and 2nd-order dynamic model. The capacities of this sorption were 588.235, 625.000, 666.667, and 714.286 mg·g−1 at 25, 35, 45, and 55 (°C), respectively. The superior sorption capacities of the uncostly ZCOBLP will make it successfully used for MnO4− ions extraction from liquid phases.