Search

Abstract This study focuses on the development of a novel self-cleaning nanofiltration membrane for the efficient removal of the cationic dye methylene blue (MB) from industrial wastewater. The membrane is composed of vinyl resin (VR), cellulose nanofibrils (CNF), and titanium alpha aluminate (TAAL) nanoparticles. The TAAL loading ranged from 1 to 5 wt%, the pH varied from 5 to 10, and the initial MB concentration ranged from 10 to 50 ppm. Using a dead-end filtration system, the (VR/CNF@TAAL) membrane with 5 wt% TAAL at pH 10 demonstrated excellent performances. It achieved a remarkable 98.6% removal efficiency for 30 ppm MB dye, with a maximum adsorption capacity of 125.8 mg/g. The adsorption kinetics analysis revealed that the process followed the pseudo-second-order model, indicating a chemisorption mechanism. The rate constant was determined to be 1.2732 × 10–3 g mg−1 min−1. The Freundlich isotherm model provided a better fit (R2 = 0.996) than the Langmuir model, suggesting multilayer adsorption on the nanocomposite membrane surface. In addition to its high adsorption and filtration capabilities, the (VR/CNF@TAAL) nanocomposite membrane exhibited cost-effectiveness and environmental friendliness as an adsorbent for MB removal from industrial wastewater. The membrane’s self-cleaning property further contributes to sustainability by reducing the need for additional chemical treatments.

Although pitch-derived carbon foam (CF) is not new, but the progress for enhanced thermal, mechanical, and catalytic dye degradations need to be explored. Numerous works were performed to improve the structural morphology and properties of the CFs by dispersing various additives. But mostly it was noticed that such additives enhanced one aspect of the CFs at the cost of other ones. In this work, various additive loadings of the functionalized graphene oxide (FGO), and functionalized titanium dioxide (FTiO2) were synergistically dispersed into the CF matrix via facile pyrolysis for the preparation of CF/FGO and CF/FGO + FTiO2 hybrid composites to improve the structural morphology and properties of the CFs. Functionalization of the graphene oxide (GO) and titanium dioxide (TiO2) nanoparticles (NPs) was performed for the purpose to decrease the possible aggregations, and enhancing the compatibility and interaction between the additives and the CF matrix. A total of seven CF composites including pure CF were synthesized and explored for their structural, thermal, mechanical, and catalytic dye degradation performances. The microstructural investigations revealed that cellular morphology, pore size, shape, and porous homogeneity of the CF composites were significantly improved after the FGO and FTiO2 loadings. The thermal and mechanical behaviors revealed that as the additives loading of the FGO and FTiO2 are increased, the thermal and mechanical responses of the CF composites are significantly improved. The maximum thermal conductivity of 27.9 W/m K was revealed by 4wt.% CF/FGO + FTiO2 hybrid composite. Similarly, the optimum compressive strength of 15.7 MPa, specific compressive strength of 3.5 10 m3, excellent stress–strain, and improved Young's modulus of 42.2 MPa was shown by 4wt.% FGO + FTiO2 hybrid composite. The catalytic activity was evaluated by degrading orange II dye in an aqueous medium under ultraviolet (UV) light irradiation. The TiO2-containing composite was found to be active and the sample with 4wt.% CF/FGO + FTiO2 hybrid composite achieved a significant 78.9% degradation of the dye within just 80 min.

The monoclinic CuO has a natural tendency to grow into sheet-like structures from alkaline solutions without the need for any specialized reaction conditions or structural directing agents. We demonstrate this growth habit of CuO by heterogeneously nucleating it onto Ni foam substrate from just the ammonical solutions of Cu salts. The growth kinetics were found to be fast and, dense, interlaced thin films with an average sheet width of 20 nm can be grown by simply controlling the degree of supersaturation of the solution. Strongly adhered films with thicknesses up-to 5 μm were deposited from three different Cu salt solutions. Due to faster growth kinetics, growth time has little effect on both the film and nanosheet thickness. Detailed structural and compositional characterizations of the CuO nanosheets were made using FESEM, HRTEM, SAED, XRD and, XPS. The utility of the grown CuO nanosheets is demonstrated as a ready to use electrode for electrochemical supercapacitors. Specific capacitance in excess of 498 F/g was calculated from the Galvanostatic charge–discharge measurements collected at a current density of 0.5 A/g.

Based on the versatile nature and applications of Carbon foam (CF), up to now many attempts were performed to improve the structure and properties of CF by incorporating various additives in the CF matrix. But these additives improved one property on the cost of another ones. Herein, we have synergistically incorporated multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO) with varying loadings as additives in the CF matrix via direct pyrolysis to achieve all the desired properties. Seven different types of CF composites including pure CF were prepared and their effect on the structure, mechanical, thermal, electrical and catalytic characteristics has been reported. The results revealed that after the inclusion of MWCNTs and GO contents, the microstructural performance of CF samples was amazingly improved. Additionally, it was observed that mechanical, thermal, electrical and catalytic behaviors of the CF samples were significantly enhances by the increase of nanohybrids. The compressive strength and Young's modulus reveals their optimum limits up to 19.3 and 57.4 MPa respectively on 2 wt.% MWCNTs-GO additive loadings. Similarly, the greatest thermal and electrical conductivities of 30.92 W/m. K and 27.4 × 103 S/m were showed by CF samples having 2 wt. % MWCNTs-GO loadings. Whereas, the decolorization activity of the CF and their nanocomposites were tested against methyl orange dye and it was observed that the sample with enhanced MWCNTs and GO have good decolorization activity and much sustainable than other samples. The 4% CF/MWCNTs-GO decolorized about 76% MO dye under exposure to UV light within 60 min. The decolorization of MO dye increases with increasing nanocomposite dosage and decreasing initial dye concentration.

Nanodiamond (ND) is becoming the core center of interest for many researchers due to its immense utilization in different fields of science. The extraordinarily unique attributes provided by NDs include biocompatibility, easy production, chemical inertness, rich surface chemistry, small size, and fluorescence resistance. In biomedical sciences, all these characteristics uplift the standards of ND particles. Recent studies on the biomedical side have been found to strengthen its significance ever since ND tested positive for utilization in diagnostics and drug delivery. In addition, NDs have been proven beneficial in the manufacturing of biodegradable surgical instruments, scaffolds for tissue engineering, and drugs to eliminate resistant microbes and viruses. Genetic materials are also delivered to the center of the nucleus with the aid of ND particles. In this review, we have discussed in detail all the benefits of NDs, their applications in sensors, ND-blood interactions, blood-contacting, orthopedics, anti-cancer agents, antimicrobial agents, and drug/gene delivery. The importance and significance of the purification, synthesis, processing, and surface functionalization of NDs have been discussed. Recent advances in modern technologies in the field of biomedical and biological sciences also have been covered in this manuscript.

Heavy metal contamination is a major environmental issue worldwide and a significant public health risk. However, developing environmentally sustainable and technically viable solutions or adsorbents for treating water contamination caused by heavy metals is urgently needed. In this work, an eco-friendly approach of obtaining a new composite material called ZrO2/GO that was prepared from the synthesized nano zirconium oxide (ZrO2) and graphene oxide (GO) prepared from spent carbon rods in zinc carbon batteries. ZrO2/GO was analyzed by XRD, SEM, BET, EDX, and FTIR to learn more about its composition and structure. The batch approach determined the optimal sorption conditions, including pH4, 50 mg ZrO2/GO, 150 mg/L U(VI), and 50 min of sorption time. ZrO2/GO was found to have a 128 mg/g sorption capacity. The Langmuir and 2nd-order kinetic equations can be exploited to elucidate the adsorption approach with reasonable accuracy. Since sorption is exothermic when it occurs naturally, thermodynamic restrictions were also envisioned. ZrO2/GO retains over 92% heavy metal ions (VI) removal efficiency even after 7 cycles. ZrO2/GO shows assurance as a potent sorbent material to extract hexavalent heavy metal ions and adsorption capacity from massive solution volumes.

The survival and growth of in vitro plantlets are still problematic for the date palm; thus, the application of nanotechnology may provide date palm plantlets that develop faster with enhanced growth and biochemical parameters. Moreover, the usage of Fe-modified activated carbon (Fe-AC) prepared from date palm pits instead of activated charcoal (AC) in tissue culture media during the current investigation can be considered an innovative approach. Furthermore, the effect of zinc oxide nanoparticles (ZnO-NPs) and bulk particles (ZnO-BPs) on the rooting and growth of date palm plantlets and on some physiological indices was also investigated. X-ray diffraction, dynamic light scattering, scanning electron microscopy, and transmission electron microscopy were used to characterize Fe-AC and ZnO-NPs. As detected from the characterization, the particle size was 720 nm for Fe-AC and 60 nm for ZnO-NPs. The obtained results indicated that AC significantly enhanced plantlet growth, plantlet height, number of leaves/plantlet, root length, number of roots/plantlet, and the concentrations of IAA, chlorophyll a and chlorophyll b compared with Fe-AC. On the other hand, sugars and phenols concentrations, and POD and PAL activities were highly increased with Fe-AC. There was no significant difference in terms of plant fresh weight (FW), leaf length, leaf width, protein, amino acids, and carotenoids. ZnO nanoparticles significantly improved plant height, leaf length, leaf width, root length, and the concentrations of IAA, chlorophylls a and b, and carotenoids; in contrast, the bulk form increased roots/plantlet, amino acids, and total sugars. Supplying the MS medium with combinations of ZnO-NPs or ZnO-BPs and AC or Fe-AC significantly increased all growth and physiological parameters. Plant height, leaf length, leaf width, root length, and the concentrations of IAA, protein, and chlorophylls a and b significantly increased when ZnO-NPs were combined with AC. Amino acids, total sugars, carotenoids, and phenols concentrations and the activities of POD and PAL increased when ZnO-BPs and Fe-AC were added together.

This research studied the enhancing effect on the nanofiltration composite (TFCNF) membrane of two non-ionic surfactants on a thin-film composite nanofiltration membrane (TFCNF) for calcite scale (CaCO3) inhibition in oilfield application to develop a multifunctional filtration system: nanofiltration, antiscalant, and scale inhibitors. The effectiveness of dodecyl phenol ethoxylate (DPE) and oleic acid ethoxylate (OAE) as novel scale inhibitors were studied using the dynamic method. Scaling tests on the membrane were performed to measure the scaling of the inhibited membrane with and without scale inhibitors for salt rejection, permeability, and flux decline. The results revealed that the TFCNF membrane flux decline was improved in the presence of scale inhibitors from 22% to about 15%. The rejection of the membrane scales increases from 72% for blank membranes, reaching 97.2% and 88% for both DPE and OAE, respectively. These confirmed that scale inhibitor DPE had superior anti-scaling properties against calcite deposits on TFCNF membranes. Inhibited scaled TFCNF membrane was characterized using environmental scanning electron (ESEM), FTIR, and XRD techniques. The results of the prepared TFCNF membrane extensively scaled by the calcite deposits were correlated to its morphology.

A cost-effective adsorbent was prepared by carbonization of pre-treated Phragmites australis reed at 500 °C. Phragmites australis was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) surface analyses. XRD of the as-prepared adsorbent exhibited a partially crystalline structure with a specific surface area of 211.6 m2/g and an average pore diameter of 4.2 nm. The biosorption potential of novel biosorbent Phragmites australis reed was investigated with a batch scale and continuous flow study. The study was conducted at different constraints to obtain optimum pH conditions, adsorbent dose, contact time, agitation speed, and initial TDS concentration. In order to analyze the properties of the procedure and determine the amount of sodium removal, Langmuir, Freundlich, and Dubinin–Radushkevich isotherms were tested. The optimal values of contact time, pH, and adsorbent dose were found to be 150 min, 4, and 10 g/L, respectively, with an agitation speed of 300 rpm at room temperature (27 °C). The three tested isotherms show that the adsorption of Na+ onto the prepared adsorbent is a hybrid process from physi- and chemisorption. For industrial application, the adsorbent was tested using the adsorbent column technique. Pseudo-first-order, pseudo-second-order, and diffusion models were connected, and it was discovered that the information fit best to the pseudo-second-arrange active model. According to the intraparticle diffusion model, the mechanism goes through four stages before reaching equilibrium. The periodicity test shows that the adsorption ability of Phragmites australis can be recovered by washing with 0.1 M HCl.

Based on the adsorption performance of a porous nanocomposite with limestone (LS), activated carbon (AC) and sodium alginate (SG), a unique, multifunctional LS–AC–SG nanocomposite absorbent was designed and prepared for extracting antibiotics and drugs from aqueous solutions. The composite exhibited the following advantages: quick and simple to prepare, multifunctionality and high efficiency. Amoxicillin (AMX) and diclofenac (DCF) were chosen as the conventional antibiotic and the drug, respectively. The prepared nanocomposite’s physicochemical characteristics were calculated through numerous characterization methods. The structure of the surface was made up of interconnected pores that can easily confine pollutants. The surface area was measured to be 27.85 m2/g through BET analysis. The results show that the maximum absorption capacity of amoxicillin and diclofenac was 99.6% and 98.4%, respectively, at a contact time of 40 min. The maximum removal of amoxicillin and diclofenac was reached at pH = 2. Adsorption analysis revealed that adsorption isotherm and kinetic data matched the pseudo-first-order kinetic and the Langmuir isotherm models. The results imply that the synthesized nanocomposites have the capacity to remove amoxicillin (AMX) and diclofenac (DCF) from aqueous solutions.

In this work, a mesoporous nanocomposite composed of nanogibbsite (α-Al(OH)3) and nanosilica was prepared. Gibbsite nanoparticles (GNPs) with a crystal size of ≈38 nm were prepared from Al-dross industrial waste products in an acidic environment at 100°C. Nanosilica (NS) with a crystal size of ≈13 nm was prepared from sodium silicate using dilute hydrochloric acid. The deposition of nanosilica onto gibbsite particles was investigated. The mesoporous silica-gibbsite (NSG) nanocomposite was examined by evaluating its ability to adsorb the toxic anionic dye Eriochrome black T (EBT) from aqueous solution. The compositional and morphological properties of NSG nanocomposites were studied by means of the FTIR spectroscopy, X-ray fluorescence (XRF), XRD, SEM, and TEM techniques. The effect of dye concentration, pH, adsorbent dose, contact time, and temperature was investigated. The sorption models, the isotherms, and the thermodynamic parameters ΔHo, ΔGo, and ΔSo were evaluated. The N2 adsorption-desorption isotherms revealed that mixing the two prepared materials (NS and GNPs) to form the NSG nanocomposite resulted in good properties (a surface area of 62.34 m2·g−1, a pore radius of 22.717 nm, and a pore volume of 0.7081 cm3·g−1). The results show that the prepared NSG nanocomposite has a remarkable ability to adsorb toxic anionic dyes.

In this work, low-cost and readily available limestone was converted into nanolimestone chitosan and mixed with alginate powder and precipitate to form a triple nanocomposite, namely limestone—chitosan–alginate (NLS/Cs/Alg.), which was used as an adsorbent for the removal of brilliant green (BG) and Congo red (CR) dyes in aqueous solutions. The adsorption studies were conducted under varying parameters, including contact time, temperature, concentration, and pH. The NLS/Cs/Alg. was characterized by SEM, FTIR, BET, and TEM techniques. The SEM images revealed that the NLS/Cs/Alg. surface structure had interconnected pores, which could easily trap the pollutants. The BET analysis established the surface area to be 20.45 m2/g. The recorded maximum experimental adsorption capacities were 2250 and 2020 mg/g for CR and BG, respectively. The adsorption processes had a good fit to the kinetic pseudo second order, which suggests that the removal mechanism was controlled by physical adsorption. The CR and BG equilibrium data had a good fit for the Freundlich isotherm, suggesting that adsorption processes occurred on the heterogeneous surface with a multilayer formation on the NLS/Cs/Alg. at equilibrium. The enthalpy change (ΔH0) was 37.7 KJ mol−1 for CR and 8.71 KJ mol−1 for BG, while the entropy change (ΔS0) was 89.1 J K−1 mol−1 for CR and 79.1 J K−1 mol−1 BG, indicating that the adsorption process was endothermic and spontaneous in nature.

In the present investigation, green nano-zerovalent copper (GnZVCu), activated carbon (AC), chitosan (CS) and alginate (ALG) nanocomposites were produced and used for the elimination of chromium (VI) from a polluted solution. The nanocomposites GnZVCu/AC-CS-alginate and AC-CS-alginate were prepared. Analysis and characterization were performed by the following techniques: X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The SEM analysis revealed that the nanocomposites are extremely mesoporous, which leads to the greatest adsorption of Cr+6 (i.e., 97.5% and 95%) for GnZVCu/AC-CS-alginate and AC-CS-alginate, respectively. The adsorption efficiency was enhanced by coupling GnZVCu with AC-CS-alginate with a contact time of 40 min. The maximum elimination of Cr+6 with the two nanocomposites was achieved at pH 2. The isotherm model, Freundlich adsorption isotherm and kinetics model and P.S.O.R kinetic models were discovered to be better suited to describe the exclusion of Cr+6 by the nanocomposites. The results suggested that the synthesized nanocomposites are promising for the segregation of Cr+6 from polluted solutions, specially the GnZVCu/AC-CS-alginate nanocomposite.

The present investigation is a comparison study of two nanocomposites: Nano-silica-coated oxyhydroxide aluminum (SiO2–AlOOH; SCB) and nano-silica-coated oxyhydroxide aluminum doped with polyaniline (SiO2–AlOOH–PANI; SBDP). The prepared nanocomposites were evaluated by monitoring the elimination of heavy metal Ni(II) ions from aquatic solutions. The synthesized nanocomposites were analyzed and described by applying scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) techniques, as well as Zeta potential distribution. In this study, two adsorbents were applied to investigate their adsorptive capacity to eliminate Ni(II) ions from aqueous solution. The obtained results revealed that SBDP nanocomposite has a higher negative zeta potential value (−47.2 mV) compared with SCB nanocomposite (−39.4 mV). The optimum adsorption was performed at pH 8, with approximately 94% adsorption for SCB and 97% adsorption for SBDP nanocomposites. The kinetics adsorption of Ni ions onto SCB and SBDP nanocomposites was studied by applying the pseudo first-order, pseudo second-order, and Mories–Weber models. The data revealed that the adsorption of Ni ions onto SCB and SBDP nanocomposites followed the pseudo second-order kinetic model. The equilibrium adsorption data were analyzed using three models: Langmuir, Freundlich, and Dubinin–Radusekevisch–Kanager Isotherm. It was concluded that the Langmuir isotherm fits the experimental results well for the SCB and SBDP nanocomposites. Thermodynamic data revealed that the adsorption process using SCB nanocomposites is an endothermic and spontaneous reaction. Meanwhile, the Ni ion sorption on SBDP nanocomposites is exothermic and spontaneous reaction.

A simple, rapid and economic procedure was presented to remove lead(II) from aqueous solution under the optimized conditions. It is based on the sorption of Pb2+ ions from aqueous solutions onto limestone fines (LS), which is an inexpensive and widespread over the globe, followed by flotation with oleic acid (HOL) surfactant. The different parameters (namely: solution pH, sorbent, surfactant and lead concentrations, shaking times, ionic strength, temperature and the presence of foreign ions) influencing the sorptive-flotation process were examined. Nearly, 99% of Pb2+ ions were removed from aqueous solutions at pH 7 after shaking for 5 min and at room temperature (~25 oC). The procedure was successfully applied to recover lead(II) spiked to some natural water samples. A mechanism for sorption and flotation is suggested.