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To obtain a kind of superhydrophobic sponge with high oil and water selectivity, the MS/TiO2/PDMS sponge was prepared via a two-step hydrophobic fabrication based on the melamine sponge (MS), tetrabutyl titanate (TBOT), and polydimethylsiloxane (PDMS). The effects of modification time, the concentrations of TBOT and PDMS on the properties of the MS/TiO2/PDMS sponge were studied, and the separation mechanism was also discussed based on the interaction between the oil and the surface of the MS/TiO2/PDMS sponge. The results suggest that under optimal conditions, the MS/TiO2/PDMS sponge show superhydrophobicity. The contact angle and adsorption capacity for oil of the MS/TiO2/PDMS sponge are 149.2° and 98.5 g·g−1, respectively, and they can be recycled for about 25 cycles after oil–water separation test. This study prepares a new composite material with high oil–water selectivity, which is a good foundation for the development and research of new oil adsorbents. HIGHLIGHTS The MS/TiO2/PDMS sponge was prepared via a two-step hydrophobic fabrication.; The contact angle of the MS/TiO2/PDMS sponge was 149.2°.; The adsorption capacity for oil of the MS/TiO2/PDMS sponge are 98.5 gg−1.; The MS/TiO2/PDMS sponge can be recycled about 25 cycles after oil-water separation test.

In this study, the crystalline metal-organic framework (MOF) ZIF-67 was obtained using the solvent-free ball milling method, which is a fast, simple, and economical green method without the need to use solvents. Using the impregnation method, platinum metal ions were loaded in the MOF cavities. Various descriptive methods have been used to explain the prepared Pt@ZIF-67 compound, such as FTIR, BET, TEM, SEM, EDS, XRD, TGA, and ICP. Based on this, the results showed that Pt nanoparticles (0.26 atom%) were located inside the pores of ZIF-67. In addition, no evidence supports their accumulation on the MOF surface. The efficiency of Pt@ZIF-67 was approved in the reduction of toxic and harmful nitrophenol compounds in water. The results showed that the removal of 4-nitrophenol in aqueous medium was successfully achieved with 94.5% conversion in an optimal time of 5 min with the use of NaBH4, and catalyzed by Pt@ZIF-67. Additionally, the Pt@ZIF-67 was recoverable and successfully tested for five qtr runs, with reasonable efficiency.

A copolymer of poly(BuMA–co–EDMA) modified with C-tetra(nonyl)calix[4]resorcinarene was obtained via the impregnation method. The formation of the modified copolymer was confirmed and investigated using various techniques; in this way, the presence of calix[4]resorcinarene was confirmed by FT-IR spectroscopy and by high resolution transmission electron microscopy. The modified copolymer was used for the removal of highly toxic cations (Pb2+, Hg2+, and Cd2+) from aqueous solutions. To perform the removal, we used the batch sorption technique and the effects of time of contact, pH, and volume of sample on the effective sorption were determined. The best results were observed for Pb2+ extraction, which was comparatively more efficient. Adsorption–desorption experiments revealed that the modified copolymer could be used for several cycles without significant loss of adsorption capacity. Finally, the results showed that the modified copolymer application is highly efficient for the removal of lead ions from aqueous solutions.

Supplementary data related to this article can be found at http://dx. doi.org/10.1016/j.micromeso.2018.06.010., Faujasite zeolite-supported niobium-based catalysts (with Nb2O5 amounts of 5 and 15wt%) were prepared by impregnation of NaY, HY, and HUSY zeolites using a niobum(V) ammonium oxalate complex. These obtained Nb-containing catalysts were calcined and thoroughly characterized by different physico-chemical techniques. The characterization results revealed that niobium oxide was successfully loaded on the surface of the zeolite supports without any significant modification of the faujasite structure. Surface area and pore volume were found to decrease with the increase in the Nb content for all the prepared catalysts. The presence of Nb was proved to increase the hydrophobicity of the zeolites and to affect surface acidity. The catalytic activity of the Nb-containing samples was evaluated in the glycerol acetalization reaction, and the Nb-HUSY catalysts were found to show the best catalytic performance., A. Araujo and C. Ferreira thank the ERASMUS program for their grants. This work has been developed under the scope of the project BioTecNorte (operation NORTE-01-0145-FEDER-000004) supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund. This work has also been financed by national funds (FCT, Fundacao para a Ciencia e a Tecnologia.), through the projects PTDC/AAGTEC/5269/2014 and Center of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/ 2016). The authors also acknowledge funding from Spanish Ministry project CTQ2014-57578-R and CTM2017-82335-R and Comunidad de Madrid Alccones, S2013/MAE-2985., info:eu-repo/semantics/publishedVersion

4 Figuras, 4 Tablas, 1 Esquema.-- This is a post-peer-review, pre-copyedit version of an article published in Wood Science and Technology. The final authenticated version is available online at: http://dx.doi.org/10.1007/s00226-018-1047-5, The fabrication of activated carbon (AC) is widely carried out by the so-called chemical activation method, in which the biomass substratum is put in touch with an impregnating chemical agent prior to the carbonization stage. Even though this methodology is known for a long time, there are many features that are still poorly understood, particularly those regarding the details of the underlying mechanisms involved during the interaction of the activating agent with the precursor, eventually leading to the development of AC. Previous research conducted in the laboratories dealt with the use of cherry stones (CS) and phosphoric acid, toward ACs with tailored porous structures, finding out that the experimental variables of the impregnation stage were crucial for their eventual characteristics. Thus, the results obtained at that time deserved further discussion, with the aim at unraveling the true nature of those findings. With such purpose, the authors comment further on the CS and H3PO4 in non-conventional impregnation methodologies, performed in the previous works. Four series of H3PO4-impregnated products were prepared in a previous research, using a wide range of impregnation strategies, aiming at controlling the loading of H3PO4 on the lignocellulosic substratum. Herein, with the mass uptake as the main, it was possible to link the uptake with the chemical changes of H3PO4 in agreement with essential chemistry knowledge. Mass gain is strongly dependent on the impregnation method, and interesting insights arise on the basis of the mass changes of CS after impregnation., Financial support by Gobierno de Extremadura and European FEDER Funds are gratefully acknowledged. Special thanks are directed toward Mr. Patrick Moosbrugger for his kind support on visual designing.

In this study, a Cu–Ce@Az ozone catalyst with multiple active components was prepared through the impregnation method to treat purified terephthalic acid (PTA) wastewater, and characterized by X-ray diffraction, X-ray fluorescence spectroscopy, scanning electron microscopy, specific surface area analysis, X-ray energy spectroscopy, X-ray photoelectron spectroscopy, and other methods. The Cu–Ce@Az ozone catalyst had a developed pore structure with a large specific surface area and crystal structure. After calcination, the metallic elements Cu and Ce existed in the state of oxides CuO and CeO2. The effects of reaction time, solution pH, catalyst dosage, and ozone dosage on the catalytic oxidation performance of the Cu–Ce@Az ozone catalyst were studied. Adding tert-butanol reduced the removal rate of COD from the PTA wastewater through the catalytic oxidation system, which proves that a Cu–Ce@Az ozone catalyst treatment process of PTA wastewater follows the free-radical reaction mechanism. The results of 3D fluorescence spectroscopy analysis show that the organic matter in the PTA wastewater was converted into tryptophan organic matter and aromatic organic matter after the reaction of the catalytic oxidation system. Ultraviolet absorption spectroscopy analysis indicated that in unsaturated chemical bonds, some conjugated structures and benzene ring structures of organic matter in the PTA wastewater were destroyed.

Magnetic nanoparticles have been synthesized on mesoporous silica by a simple method without the need for either an alkali or an organic solvent, nor for rigorous pH control, making it a safe procedure for the nanomedicine field. The systems have been exhaustively characterized through different instrumental techniques, including the analysis of physicochemical properties by N2 adsorption, TEM, HAADF/STEM, SAED, EDS, XRD, XPS, and UV/Vis DRS. Magnetic properties have been tested by means of magnetization curves at room temperature and 5 K, ZFC-FC curves, and Mössbauer spectroscopy. The nanocomposite obtained by heating in N2 atmosphere showed good specific surface area and structural order, as well as high magnetization and negligible magnetic hysteresis and remanence, arising from the presence of finely dispersed magnetite nanospecies. These features are very relevant for future application as carriers for drug delivery systems, among other uses. Fil: Cuello, Natalia Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigación y Tecnología Química. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Tecnología Química; Argentina Fil: Oliva, Marcos Iván. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina Fil: RodrÍguez Torres, Claudia Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; Argentina Fil: Tolley, Alfredo Juan. Centro Atómicobariloche,cnea-conicet; Argentina Fil: Elías, Verónica Rita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigación y Tecnología Química. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Tecnología Química; Argentina Fil: Eimer, Griselda Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigación y Tecnología Química. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Tecnología Química; Argentina

The current study reports the synthesis, characterization and catalytic activity of tungstophosphoric acid (HPW) and its potassium salts (KH2PW and K3PW) supported on activated carbon (AC). Because potassium salts of tungstophosphoric acid are insoluble, the carbon supported KH2PW and K3PW were prepared by a two step impregnation method. The synthesized catalysts were characterized by various physicochemical methods such as Fourier transform infrared and Raman spectroscopy, differential thermal analysis, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy and nitrogen physisorption. It is observed that all active phases keep their Keggin-type structure after being supported on AC, while their specific surface area is considerably increased by deposition on this porous substrate. The results also indicated that the synthesized materials retained the morphology specific for the support as well as its thermal properties. The adsorption behaviour of the nanocomposites towards nicosulfuron pesticide was found to be particulary good and even slightly improved when compared to pure activated carbon. The catalytic activity of the prepared catalysts was probed for the vapor phase dehydration of ethanol at 300 °C. The conversion of ethanol and selectivity toward ethylene and diethyl ether of nanocomposites were compared with the values of bare HPW, KH2PW and K3PW. Results revealed that catalytic activity depends on the catalyst type and active phase loading. The conversion over unsupported catalysts decreased by increasing the cation content per Keggin unit. The nanocomposites with 30 wt% loading of HPW achieved the best conversion of nearly 100% and the highest and stable selectivity toward ethylene. The catalytic activity of nanocomposites with acidic KH2PW showed lower catalytic activity of about 70%, while the nanocomposites of neutral K3PW and AC showed negligible activity.

The study provides comprehensive information on the vacuum impregnation process applied to plant materials. It aims (in traditional applications) to ensure impermeability and elimination of porosity of various materials. The process substantially accelerates mass transfer in the liquid&ndash, solid system. The study describes the course of the process and accompanying phenomena as well its effects on plant tissues. The aim of the investigations was to determine the impact of some impregnation parameters (pressure, pressure change rate, vacuum maintenance time, relaxation time, and the coefficient of impregnating liquid viscosity) and the mode of impregnation (wet, dry, cyclic wet) on the degree of filling the plant tissue with the impregnating solution. Jonagold apples were used as the study material. The investigations have revealed that changes in the vacuum impregnation parameters (vacuum maintenance time, relaxation time, pressure change rate in the system) and the impregnation method do not exert a significant impact on the effectiveness of the process as expressed by the degree of permeation of the impregnating solution into the tissue. The pressure value and the viscosity coefficient were the only parameters that had a significant effect on the impregnation yield.

Here we report the synthesis of CrN co-doped ZnO for the first time. Zinc oxide (ZnO) nanoparticles were synthesized by direct precipitation method via the reaction between zinc nitrate [Zn(NO3)2 .6H2O] and ammonium carbonate [(NH4)2CO3] in aqueous solutions with proper concentration. Modified photocatalysts were synthesized by the incipient wetness impregnation method (chromium-doped ZnO) and by solid state reactions using ZnO and urea as precursors (nitrogen-doped ZnO). Chromium-nitrogen co-doped ZnO nanomaterials were prepared from the already prepared N-doped ZnO nanomaterials via one step impregnation method. The as-synthesized photocatalysts were investigated by XRD, BET, SEM-EDX, FTIR, and UV–Vis techniques. Photocatalytic degradation of thymol blue using as-synthesized photocatalysts was studied under visible as well as UV irradiations. Highest photocatalytic degradation efficiency of chromium-nitrogen co-doped zinc oxide could be attributed to the lower rate of recombination of the photo-generated electrons and holes as well as to its lower band gap energy as the result of the co-doping. Photocatalytic degradation is found to follow pseudo first order kinetics., IDThe financial support from the Spanish Government MINECO (project MAT2012-31127) is acknowledged., Publisher's version

The effects of impregnation methods (co-impregnation and sequential impregnation) and drying conditions (air and vacuum) on the structure and catalytic behavior of MCM-41 supported Ni-W catalysts were investigated. The catalysts were characterized by powder X-ray diffraction (XRD) analysis, Fourier-transform infrared spectroscopy (FT-IR), diffuse reflectance UV-Vis absorbance spectroscopy (DRS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and pyridine adsorbed infrared spectroscopy (Py-IR) techniques. They were tested for hydrodenitrogenation (HDN) of quinoline at temperatures of 300-400 ºC. The HDN results showed that the catalysts prepared by co-impregnation were more active than the catalysts prepared by sequential impregnation and the catalysts prepared by drying under vacuum were more active than the catalysts dried in air. Characterization revealed that the co-impregnation method and drying under vacuum promoted the dispersion of W, the formation of the active phases, and the formation of acidic sites on the catalysts. Os efeitos dos métodos de impregnação (co-impregnação e impregnação sequencial) e das condições de secagem (ar e vácuo) sobre estrutura e o comportamento catalítico de catalisadores Ni-W suportados em MCM-41 foram investigados. Os catalisadores foram caracterizados por difratometria de raios X de pó (XRD), espectroscopia de absorção no infravermelho com transformada de Fourier (FT-IR), espectroscopia de absorção no UV-Vis por refletância difusa (DRS), espectroscopia Raman, espectroscopia fotoeletrônica de raios X (XPS) e espectroscopia de absorção no infravermelho após adsorção de piridina (Py-IR). Eles foram testados para hidrodesnitrogenação (HDN) de quinolina nas temperaturas de 300-400 ºC. Os resultados de HDN mostraram que os catalisadores preparados por co-impregnação foram mais ativos do que aqueles preparados por impregnação sequencial, e que os catalisadores preparados por secagem sob vácuo foram mais ativos do que aqueles secados ao ar. A caracterização revelou que o método de co-impregnação e a secagem sob vácuo promoveram a dispersão de W, a formação de fases ativas e a formação de sítios ácidos na superfície dos catalisadores.

Carbon supported hydrous ruthenium oxide was prepared by ail ultrasonic threatment of carbon black-RuOxHy sol mixture (impregnation). Black Pearl 2000(R) was used as a supporting material, while an oxide sol was prepared by forced hydrolysis of hydrous RuCl3. The influence of kthe RuOxHy sol aging time and the amount of oxide solid phase in the impregnating medium oil the capacitive behavior of prepared carbon supported hydrous ruthenium oxide was investigated by cyclic voltammetry and electrochemical impedance spectroscopy. The oxide amount in the composite increases with increasing concentration of oxide particles in the impregnating medium. The composite specific capacitance decreases with increasing aging time of oxide sol, while increases with increasing concentration of oxide particles in the impregnating medium. Transition line model fits well the composite impedance behavior indicating a distinctive capacitive response of the inner and the outer composite active surface. This distinction becomes more pronounced as the amount of oxide in the composite increases.