This study aims to eliminate hexavalent chromium Cr(VI) ions from water using pomegranate peel (PGP) powder. Dynamic measurements are carried out to examine the influence of the operating factors on ...the adsorption efficiency and kinetics. The analyzed PGP is found to be amorphous with relatively high stability, contains hydroxyl and carboxyl functional groups, a pH of zero charge of 3.9, and a specific surface-area of 40.38 m2/g. Adsorption tests indicate that PGP exhibits excellent removal effectiveness for Cr(VI) reaching 50.32 mg/g while the adsorption process obeys the Freundlich model. The thermodynamic study favors the exothermic physical adsorption process. The influence of operating parameters like the flow rate (1 to 3 mL/min), bed height (25 to 75 mm), concentration (10 to 30 mg/L), and temperature (298 to 318 K) on the adsorption process are investigated in column mode. To assess the performance characteristics of the column adsorption data, a non-linear regression has been used to fit and analyze four different kinetic and theoretical models, namely, Bohart-Adams, Thomas model, Clark, and Dose response. The obtained experimental results were found to obey the Dose Response model with a coefficient of regression R2 greater than 0.977. This study proved the excellent efficiency in the treatment of chemical industry effluents by using cost-effect abundant biowaste sorbent. This research demonstrated great efficacy in the treatment of chemical industrial effluents by using an abundant, cost-effective biowaste sorbent, thereby achieving the UN SDGs (UN Sustainable Development Goals) primary objective.
AbstractFood dyes with a diverse set of colorants stimulate appetite and enhance aesthetic charm of food on table but at the same time these dyes contaminate the aquatic and biological ecosystems due ...to their cytotoxic and carcinogenic potentials. Herein, we report magnetite catalyzed removal of sunset yellow dye from water through catalytic degradation and ozonation. The magnetite catalyst revealed about 83% catalytic degradation and 92% catalytic ozonation performance toward sunset yellow dye at 100 and 25 min, respectively. Furthermore, the persulphate/magnetite/O3 hybrid system revealed superior performance compared to the persulphate/magnetite under identical conditions. Kinetic studies revealed that the dye degradation data followed second-order kinetics, suggesting that the dye removal process is physicochemical in nature. This study further demonstrates that the persulfate/magnetite/O3 hybrid system can efficiently decompose sunset yellow dye in aqueous solution compared to the Fenton’s reagent and simple catalytic decomposition processes which is attributed to its unique structural features.
It is highly desirable and of utmost importance to find eco-friendly and green approaches for a sustainable environment. Nowadays researchers from different communities have determined that it is ...economical and highly demanding to synthesize green nanomaterials by utilizing plants, fruits, yeast, algae, fungi, and other green techniques as stabilizers and mediators. Compared to the chemical synthesis techniques, the plant-mediated approach is considered an eco-friendly, efficient, easy, stable, and cost-effective means for the synthesis of nanomaterials. Among various nano-size materials, Graphitic carbon nitride, g-C3N4, (CN) belongs to a new class of multifunctional metal-free n-type semiconductors. It has a polymeric structure with many potential applications in agriculture and energy sectors and other fields. So, it is highly demanding to explore the green synthesis approaches and their utilization for nanomaterials, especially g-C3N4. In this review, we comprehensively explored the green g-C3N4 based nanomaterials, their preparation, properties, applications, and opportunities. Adding more, this study aims to explore all feasible green synthesis approaches, applications, characterization techniques, and modification methods. Apart from this, the current statutes and future prospectus of the green g-C3N4 based nanomaterials are also explored. Finally, this work will open a new gateway for the synthesis of green g-C3N4 based nanomaterials and their utilization for a sustainable environment.
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With the use of facile single-step calcination of Zinc glutamate MOF and melamine, highly efficient ZnO/g-C3N4 nanocomposite was prepared and utilized in photocatalytic degradation of ...Rhodamine B (RhB), an organic pollutant. The composite's morphology, crystallinity, optical properties, and composition were determined using several analytical techniques, which include scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), diffuse reflectance spectroscopy. The degradation of RhB over the optimized 1.0%ZnO/g-C3N4 composite is ∼1.77 fold higher compared to the pure g-C3N4 under identical conditions. The synergistic interfacial interaction between g-C3N4 and MOF derived ZnO remarkably improved the electron-hole pairs separation, which led to the exceptionally high photocatalytic activity of the composite photocatalysts. Based on the radical scavenger tests and ESR analysis, it is confirmed that •O2− as the dominant active specie facilitated the degradation of RhB over the as-prepared ZnO/g-C3N4 composites. This work will open up new insights for further research on g-C3N4 based composite materials.
A simple design and low cost miniaturized reactor integrated with interchangeable thin film TiO
2
nanolayer was successfully fabricated for the photocatalytic degradation of azo dyes. The TiO
2
...nanofilms were prepared by sol-gel dip-coating method, while the miniaturized reactor was fabricated on poly methyl methacrylate (PMMA) substrates, using a laser cutting machine. The performance of the miniaturized reactor for the photocatalytic degradation process was investigated for the degradation of a commercial dye (Novacron Red C-2BL). About 98% degradation of the commercial dye was achieved after 100 min in a stopped flow system, and 15% in a continuous flow system. The effect of different operating variables such as pH, initial flow rate, light intensity, layers of the nanoparticles, and temperature on the photocatalytic degradation was studied and the optimum operating conditions were determined to be: inlet flow rate of 0.05 ml/s, pH of 7, UV power 82 W and using a multi-layer of TiO
2
thin film in the miniaturized reactor. The reaction kinetics was described as pseudo first order kinetics and rationalized using the Langmuir-Hinshelwood model.
Nowadays, the use of eco-friendly additives in drilling fluids to improve rheological properties is widespread. This work aims to examine and assess the rheological characteristics and fluid loss of ...drilling fluid suspensions containing Algerian Na-Bentonite (NaB) and potato starch (PS) as viscosifier upon the addition of grass powder (GP). The obtained results indicate that the aging tests applied on different drilling fluid suspensions during 192 h at (20 °C) reduce the values of apparent viscosity by an average of (14.3%), plastic viscosity (22.2%), yield point (6.7%), and shear stress (47.3%) when varying the (PS) concentration in the suspensions (0.6, 1.2, 2%) as well as the values of fluid loss (9.5%); meanwhile, the values of initial and final gel strength are increased (32.6% and 19.6%, respectively). Subsequently, the possibility to further improve the rheological properties of drilling fluid suspensions using an environment eco-friendly additive (GP) has been studied. The introduction of (3, 6, 9 g) GP in the aged suspensions increases the values of rheological properties, i.e., the highest efficiency of 18.4% has been achieved by adding 9 g of GP to 2% (PS) aged suspension. The fluid loss test indicates that increasing the (GP) concentration in the (NaB+PS) suspension reduces the fluid loss volume by 36.42%. This study demonstrates the synergy of combining cost-effective GP to (NaB+PS) in aged drilling fluids by enhancing significantly its rheological properties besides a better environmental protection.
AbstractElectrochromic (EC) thin films have received considerable attention due to their potential applications in various fields such as smart windows, electrochromic displays, and energy storage ...devices. This review highlights various methods used for the fabrication and functionalization of EC films for various applications. Various techniques for EC thin film deposition ranging from solution-processable, low-temperature approaches such as sol-gel, spin coating, dip coating, and spray pyrolysis, to advanced techniques for deposition such as physical vapor deposition, chemical vapor deposition, and sputtering are summarized in this review. In addition, various applications of EC thin films and the outcome of different deposition approaches on the opto-electrochromic properties of EC thin films have been discussed elaborately. This review has the potential to spark the interest of researchers from a broad range of disciplines, including photocatalysis, electrocatalysis, nanotechnology and materials science.
The rapid formation of spherical and hexagonal silver nanostructures (Ag colloid particles of different shapes) through microwave irradiation was investigated. Silver nanoparticles were successfully ...fabricated by reduction of Ag
+
in a water medium and using polyvinylpyrrolidone as stabilizing and ethanol as reducing agents, while varying microwave power. The preliminary synthesis of silver nanoparticles was observed through the color change of the solution, from colorless transparent to brown. Morphological observations using transmission electronic microscopy indicated the formation of spherical-shaped particles at the nanoscale regime (2–100 nm) with high crystalline nature. Elementary analysis confirms the purity of AgNPs and surface plasmon resonance reactivity of their specific surface. UV–Visible spectroscopy revealed the existence of two kinds of AgNPs: metallic and ionic species exhibiting an interesting optical property in the ultraviolet range. The auto-correlation function measured by dynamic light scattering displayed a monodispersed character of AgNPs with an average particle size around 111 nm. Additionally, the antibacterial activity measured by Kirby–Bauer method indicated that silver nanoparticles exhibit high antibacterial activity against Gram
+
bacteria such as
Staphylococcus aureus
M55A and Gram
−
such as
Escherichia coli
BCSE,
Klebsiella pneumoniae
Kpc+ ,
Salmonella
spp.
Silver nanoparticles (Ag NPs) exhibit antibacterial activity and are extensively used in numerous applications. The aim of this study was to examine the toxic effect of Ag NPs on the marine ...microalga,
The microalgae, at the exponential growth phase, were treated with different concentrations of Ag NPs (50 and 100 nm) for 96 h. X-Ray diffraction (XRD) results indicated that the used NPs are single and pure Ag phase with a mean crystallite size of 21 and 32 nm. Ag NPs were found to have a negative effect on viable cell concentration, a variable effect on chlorophyll
concentration, and increased ROS formation. Transmission electron microscopy (TEM) analysis revealed that Ag NPs were present inside the microalgae cells and formed large aggregates in the culture medium. Ag
ions, in the form of AgNO
, were also assessed at higher concentrations and found to cause inhibitory effects.
Modern industries rapid expansion has heightened energy needs and accelerated fossil fuel depletion, contributing to global warming. Additionally, organic pollutants present substantial risks to ...aquatic ecosystems due to their stability, insolubility, and non-biodegradability. Scientists are currently researching high-performance materials to address these issues. LaFeO3 nanosheets (LFO-NS) were synthesized in this study using a solvothermal method with polyvinylpyrrolidone (PVP) as a soft template. The LFO-NS demonstrate superior performance, large surface area and charge separation than that of LaFeO3 nanoparticles (LFO-NP). The LFO-NS performance is further upgraded by incorporating ZIF-67. Our results confirmed the ZIF-67/LFO-NS nanocomposite have superior performances than pure LFO-NP and ZIF-67. The integration of ZIF-67 has enhanced the charge separation and promote the surface area of LFO-NSwhich was confirmed by various characterization techniques including TEM, HRTEM, DRS, EDX, XRD, FS, XPS, FT-IR, BET, PL, and RAMAN. The 5ZIF-67/LFO-NS sample showed significant activities for CO2 conversion, malachite green degradation, and antibiotics (cefazolin, oxacillin, and vancomycin) degradation. Furthermore, stability tests have confirmed that our optimal sample very active and stable. Furthermore, based on scavenger experiments and the photocatalytic degradation pathways, it has been established that H+ and •O2− are vital in the decomposition of MG and antibiotics. Our research work will open new gateways to prepare MOFs-Perovskites nanocatalysts for exceptional CO2 conversion, organic pollutants and antibiotics degradation.
A schematic illustration of ZIF-67/LFO-NS for CO2 conversion, MG and antibiotics degradation. Display omitted
•The LaFeO3 nanosheets are prepared.•The coupling of ZIF-67 with LaFeO3 nanosheets enhanced charge separation, activated the surface, and improved the activities.•The as-prepared samples showed exceptional visible light activities for CO2 conversion, malachite green, and antibiotic degradation.•The degradation pathways are proposed.
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