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CuFeO2/CeO2 as a novel synergistic catalyst for EF removal of organic pollutants was synthesized. © 2019 Elsevier Ltd  

Kinetics and isotherms of adsorption behavior of nanoscale Zr-based metal-organic framework for the removal of three organic dyes including acidic, direct and basic ones from aqueous solutions were studied by sorption models. Nanocube-shaped UiO-66 particles with an average edge length of 215 nm, specific surface area of 1215 m2/g, total pore volume of 0.58 cm3/g, and average pore diameter of 1.8 nm were prepared by solvothermal methods. Analyzing of the equilibrium isotherms indicates that direct dye removal is best fitted with the Langmuir isotherm. Study of the adsorption kinetics also determines that direct dye adsorption follows pseudo-first-order model (R2=0.99). The kinetics of basic... 

In this work, for the first time, we presented a novel design strategy to fabricate a new type of Octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS)-based Alg/PAAm DN gels, consisting of PAAm gel as the first chemical network and Alg/OA-POSS gel as the second chemical-physical network. Incorporation of OA-POSS nanoparticles with various feed ratio into the second network not only led to form strong coordination interactions but also in comparison to the other Alg/PAAm gels demonstrated superior mechanical properties. pH, temperature, contact time and salt effects parameters were studied on the swelling and dye removal properties of the synthesized DN hybrid... 

Although morphological disorder of nanotube structure is further down than the nanoparticular electrode, its density of traps are the hindering effects in the charge transport. In this study, crack-free TiO2 nanotube membranes, which obtained through a re-anodizing process, are fixed on transparent fluorine–tin-oxide glass by applying a few drops of Titanium Isopropoxide without needing the TiO2 powder paste. Front-side illuminated dye sensitized solar cells fabricated by undoped, N-doped and blue TiO2 nanotube membranes are investigated. The electrical characteristics of TiO2 nanotube based dye sensitized solar cells are followed by theoretical analysis using simple one-diode model.... 

Despite previous researches on ion-engineered waterflooding (IEWF), its underlying mechanisms are not fully understood, particularly in presence of additives, like surfactants. This paper concerned with the contribution of Ca 2+ , Mg 2+ , SO 4 2- and Na + into altering wettability of oil-wet carbonate minerals towards water preferred state. As a mechanistic study, an experiment workflow was conducted to probe the impact of ions' concentrations in SW, either with or without sodium dodecylbenzene sulfonate (SDBS) which is an anionic surfactant. At first, contact angle (CA) measurement was carried out to evaluate the degree of wettability reversal upon treating the oil-aged calcite slabs with... 

One of the appealing usages of metal–organic frameworks is their application in manufacturing of metal oxide and metal oxide nanocomposites. In the present study, we used zeolitic imidazolate framework (ZIF-8) as precursor to prepare a new Ag/C/ZnO catalyst. The as-prepared samples were characterized using X-ray diffraction, Fourier-transform infrared, scanning electron microscopy and transmission electron microscopy analysis. Improved catalytic performance of as-prepared Ag/C/ZnO was confirmed by reduction of organic pollutants including p-nitrophenol, methylene blue and rhodamine-B in the presence of NaBH 4 in aqueous media. The synergistic effect between Ag and ZnO was proposed as the... 

The chitosan/poly vinyl alcohol membrane was modified by addition of some amine group to the membrane structure utilizing polyethyleneimine (PEI) in order to increase ionic metals adsorbent properties of the membrane. The removal percentage of the modified membranes was compared with the pristine membrane and activated carbon as common adsorbents. The membranes were characterized by FTIR, SEM, swelling degree and porosity measurement. The removal percentage of the membrane containing 0.5 wt.% PEI was more than 60% higher than the activated carbon and more than 40% higher than the pristine membrane. The modified membrane showed excellent adsorption capacity of 112.13, 86.08, and 75.5 mg/g for... 

In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nanodiamonds (ONDs), as adsorbents for selective adsorption of methylene blue (MB) and methyl orange (MO) from aqueous media, was examined. The adsorption isotherm, initial pH, ionic strength, and thermodynamic study were investigated in batch experiments. The equilibrium adsorption data were analyzed by Langmuir and Freundlich isotherm models, which indicated that the isotherms were well fitted with the Langmuir model for both dyes. Thermodynamic parameters indicated that the adsorption operation was a feasible, spontaneous, and physisorption process in experimental conditions. Meanwhile, the... 

The nanocomposite of g-C 3 N 4 supported by MIL-88A has been prepared via a facile hydrothermal method. The photocatalytic performance of as-prepared composite (MIL-88A/g-C 3 N 4 ) was examined by the degradation of the Methylene Blue (MB) solution under visible light. The characterization test illustrated that the MIL-88A particles were successfully dispersed on the surface of g-C 3 N 4 structure. Photoactivity results demonstrated that the MIL-88A/g-C 3 N 4 /H 2 O 2 exhibited dramatically visible light photocatalytic performance. Hydroxyl radicals ([rad]OH) are generated by dissociation of H 2 O 2 under visible irradiation can remarkably enhance the degradation rate of MB molecules.... 

In this study, we synthesized novel visible light photocatalyst MIL-88A/BiOI using depositing BiOI particles on the surface of a metal–organic framework (MIL-88A). Photocatalytic application of binary composite MIL-88A/BiOI was obtained by discoloration of Methylene Blue (MB) and Acid Blue 92 (AB92) in aqueous solution under visible light source. The photodegradation experiments for treating organic dyes show that the MIL-88A/BiOI heterojunction structure possess a higher rate for decomposition of dyes due to the decreased aggregation of the BiOI nanoparticles, effective charge carrier separation and the synergistic effect between MIL-88A and BiOI samples as a heterojunction. Also, the... 

The unique properties of graphene oxide (GO) nanosheets were integrated with the superparamagnetic characteristics of the CuFe2O4 nanoparticles to synthesize the magnetic graphene oxide (MGO), which was chemically modified with 3-amino propyl trimethoxy silane (APTMS) to functionalize the amine group on MGO (MGO-NH2). Afterward, MGO-NH2 was activated with glutaraldehyde (GLU) as a crosslinking agent to synthesize the functionalized MGO (fMGO) and its capability toward covalent Laccase immobilization was investigated. The comprehensive structural analysis using various characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating... 

Herein, Kiwi peel activated carbon (AC), Materials Institute Lavoisier (MIL-88B (Fe), and AC/MIL-88B (Fe) composite were synthesized and used as catalysts to degrade Reactive Red 198. The material properties were analyzed by the FTIR, BET-BJH, XRD, FESEM, EDX, TGA, and UV–Vis/DRS. The BET surface area of AC, MIL-88B (Fe) and AC/MIL-88B (Fe) was 1113.3, 150.7, and 199.4 m2/g, respectively. The band gap values (Eg) estimated by Tauc plot method, were obtained 5.06, 4.19 and 3.79 eV for AC, MIL-88B (Fe) and AC/MIL-88B (Fe), respectively. The results indicated that the AC/MIL-88B (Fe) composite had higher photocatalytic activity (99%) than that of pure AC (79%) and MIL-88B (Fe) catalysts (87%).... 

In this study, graphene oxide (GO) was synthesized via modified Hummer's method and exploited as an ideal enzyme immobilization support due to its exclusive chemical and structural features. Then, laccase from genetically modified Aspergillus was covalently immobilized onto GO (nanobiocatalyst). Enzymatic characterization of the nanobiocatalyst exhibited promising results: laccase loading of 156.5 mg g−1 and immobilization yield of 64.6% at laccase concentration of 0.9 mg/ mL. Further employment of various structural characterization techniques including Fourier Transform Infrared Spectroscopy (FTIR), X-ray Powder Diffraction (XRD), Scanning Electron Microscopy (SEM), Thermo-Gravimetric... 

Novel montmorillonite (Mt) chitosan/poly(vinyl alcohol) (PVA) nanocomposite electrospun nanofibrous membranes (ENM) were prepared and utilized for the treatment of colored wastewater. The Mt. with different mass percentages (0, 1.0, 2.0 and 3.0 mass%) was added to the membrane structure, and its effect on morphology, pore size, porosity, mechanical strength, and permeation properties of ENM were investigated. The fabricated membranes were used as affinity membranes for dye removal with ultrafast permeating adsorption. The results showed that incorporating Mt. as a reinforcing agent improved the nanocomposite ENM resistance to compaction. Young's modulus for the prepared membranes increased... 

A new poly (acrylonitrile) (PAN)-based gel polymer electrolyte (GPE) is fabricated to study the effect of carbon nanotube (CNT) on dye-sensitized solar cell (DSSC) efficiency. The GPEs are examined using electrochemical impedance spectroscopy (EIS) to analyze ionic conductivity. A maximum of 4.45 mS cm −1 ionic conductivity is achieved at room temperature with incorporation of 11 wt.% CNT. Performance of DSSC is examined with a solar simulator, and the highest energy conversion efficiency of 8.87% is achieved with the addition of 11 wt.% CNT. All GPE samples are found to follow Arrhenius model with temperature-dependent ionic conductivity testing. Structural properties are also characterized... 

This study introduces a new and bio-friendly adsorbent based on natural and cetyltrimethylammonium bromide (CTAB) modified adsorbent, celery (Apium graveolens) residue for removal of organic pollutants. The adsorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and pHpzc techniques. Removal applicability and efficiency of this biosorbent were studied using Congo red (CR) as a sample organic pollutant. To reach the best results, main parameters such as pH, adsorbent mass, contact time, initial dye concentration and temperature were optimized through the adsorption experiments in a batch system. The kinetic and isotherm of CR removal... 

In the current work, the performance of untreated nanodiamonds (UNDs) and thermally oxidized nanodiamonds (ONDs), as adsorbents for selective adsorption of methylene blue (MB) and methyl orange (MO) from aqueous media, was examined. The adsorption isotherm, initial pH, ionic strength, and thermodynamic study were investigated in batch experiments. The equilibrium adsorption data were analyzed by Langmuir and Freundlich isotherm models, which indicated that the isotherms were well fitted with the Langmuir model for both dyes. Thermodynamic parameters indicated that the adsorption operation was a feasible, spontaneous, and physisorption process in experimental conditions. Meanwhile, the... 

Magnetic reduced graphene oxide/polymer nanocomposites were prepared by in situ polymerization and grafting of polyacrylamide on the surface of functionalized magnetic reduced graphene oxide (rGO). Graphene oxide nanosheets were decorated with Fe3O4 nanoparticles, reduced and functionalized with 3-(trimethoxysilyl)propyl methacrylate, and then grafted with polyacrylamide. Grafting of polyacrylamide makes magnetic rGO hydrophilic and highly water dispersible. The prepared material was used as adsorbent for removal of an anionic dye, Congo red, and a maximum adsorption capacity up to 166.7 mg g−1 was obtained. The kinetics and isotherm of adsorption and the effect of experimental condition on... 

Biological treatment, especially enzymatic methods, can be employed for effective and environmental- friendly treatment of dye effluents. Laccase, belonging to the blue multi-copper oxidases category, can oxidize a wide variety of substrates, especially synthetic dyes. In this study, laccase was used to biodegrade two azo dyes, i.e., Direct Red 23 and Acid Blue 92. Before conducting the experiments, the laccase used in this study was enzymatically characterized. Face-centered central composite design (FCCCD) was used to optimize the main parameters of the decolorization process. The optimum conditions to maximize the bio-decolorization process of AB92 were X1=11.85 mg L-1, X2=5.10, and... 

Herein, magnetic metal-organic framework nanocomposite (ZIF-8@SiO2@MnFe2O4) was synthesized. The ultrasound-assisted simultaneous adsorption of Malachite Green (MG) and Methyl Orange (MO) as cationic and anionic dyes onto ZIF-8@SiO2@MnFe2O4 magnetic microporous nanocomposite (MMNC) as a novel adsorbent was investigated. The FTIR, FESEM, TEM, XRD, BET and VSM were used to characterize the prepared adsorbent. The analysis of dyes concentration in a binary mixture was investigated using zero-order and first order derivative spectrophotometry. The individual effects and possible interactions between the various parameters were investigated by response surface methodology (RSM). The optimized...