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In this study, a novel composited catalyst (AgFe/biochar) was synthesized using sago cycas as carbon sources by a simple method and then used to activate peroxydisulfate for the degradation of Acid Orange II. The Ag0 in the AgFe/biochar was formed in the presence of biochar whereas the bimetallic oxide (AgFeO 2) was produced in the absence of biochar, which was attributed to the role of defect in biochar. This novel catalyst exhibited remarkably higher catalytic activity, as compared to other catalysts. The scavenging experiments and electron spin resonance results indicated that it coexisted the radical and non-radical species. It is confirmed that Ag+/ Ag0, Fe3+/Fe2+, defective sites and oxygen-containing groups in biochar were demonstrated to be extremely essential in the activating peroxydisulfate. This work not only offered a feasible approach for the synthesis of novel AgFe/biochar composites but also provided a useful method for the activation of peroxydisulfate to effectively remove organic pollutants in wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, a novel composited catalyst (AgFe/biochar) was synthesized using sago cycas as carbon sources by a simple method and then used to activate peroxydisulfate for the degradation of Acid Orange II. The Ag0 in the AgFe/biochar was formed in the presence of biochar whereas the bimetallic oxide (AgFeO 2) was produced in the absence of biochar, which was attributed to the role of defect in biochar. This novel catalyst exhibited remarkably higher catalytic activity, as compared to other catalysts. The scavenging experiments and electron spin resonance results indicated that it coexisted the radical and non-radical species. It is confirmed that Ag+/ Ag0, Fe3+/Fe2+, defective sites and oxygen-containing groups in biochar were demonstrated to be extremely essential in the activating peroxydisulfate. This work not only offered a feasible approach for the synthesis of novel AgFe/biochar composites but also provided a useful method for the activation of peroxydisulfate to effectively remove organic pollutants in wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

The deactivation and regeneration of the ZSM-5-based catalyst was investigated in the reaction of acrolein diethyl acetal and ammonia toward pyridine and 3-picoline. The coke was the main reason leading to deactivation for all the tested catalysts, and it was basically combusted at high temperature under the air and water streams in order to recover the initial catalytic performance. The best catalyst through the reaction-regeneration treatment could effectively promote the formation of pyridine and 3-picoline. The results showed that the total yield of pyridine and 3-picoline was raised above 20% while the reaction was operated the 10th reaction-regeneration cycle relative to the 1st reaction at TOS (time on stream) = 1–3 h. The catalysts were characterized by means of XRD, N 2 -physisorption, FT-IR and NH 3 -TPD techniques. By relating the performance and structure of the catalyst, it was found that the dealumination and the residual coke were responsible for boosting the catalytic activity after several reaction-regeneration cycles. The dealumination generated more mesopores and less acidity while the residual coke resulted in lowering the acidity. The relationship between the catalyst and the regeneration was well established. [ABSTRACT FROM AUTHOR]

A novel route for the synthesis of 3-picoline from glycerol via liquid phase reaction under mild condition, using microwave irradiation, had been well established. The heating mode had a profound effect on the yield of 3-picoline. The formation of 3-picoline could be promoted significantly by microwave heating, however, only very little amount of 3-picoline was generated by conventional heating under the reaction conditions employed in this study. Influencing factors were systemically investigated on the basis of a HAc-catalyzed under microwave irradiation. Additionally, a lot of heterogeneous catalysts were screened. It was found that as high as a 71% yield of 3-picoline was obtained with the mass ratio of pure glycerol/ammonium acetate/acetic acid/TiO2 = 1/3/10/0.2 at 373 K, after only 20 min of microwave irradiation. A catalyst pair (HAc and TiO2) exhibited better catalytic performance relative to other catalysts in this work. Accordingly, microwave assistance together with the catalysts achieved effective transformation of glycerol to 3-picoline under mild conditions. The related plausible reaction mechanisms were also proposed. [ABSTRACT FROM AUTHOR]

A novel pathway for the synthesis of pyridine and 3-picoline was developed in this work. The method involved the condensation of gas-phase acrolein diethyl acetal and ammonia over the ZnO/HZSM-5 catalyst in a fixed-bed reactor. The problem of polymerization in existing process was effectively solved. The ZnO/HZSM-5 catalyst was proved to be the most promising catalyst relative to the ZnO/Al 2 O 3 and ZnO/HY ones. The reaction conditions and preparation conditions of the ZnO/HZSM-5 catalyst had great influences on the total yield of pyridine and 3-picoline. Characterization of ZnO/HZSM-5 had been done using X-ray diffraction (XRD), N 2 adsorption–desorption isotherms, ammonia temperature programmed desorption (NH 3 -TPD) and X-ray photoelectron spectroscopy (XPS) techniques. The characterized results revealed change of the pore structure and acidity of the catalyst upon ZnO introduction. The superior specific activity of ZnO/HZSM-5 was attributed to enhancing the various processes such as dehydrogenation in the addressed reaction. The raw materials from biological sources are possible for the synthesis of pyridine and 3-picoline in industry. [ABSTRACT FROM AUTHOR]

Hydrophobic cerium dioxide (CeO 2 ) nanomaterial, consisting of numerous open-ended nanotubes, was synthesized via a hydrothermal method without further chemical modification. The as-synthesized material displays water contact angle (CA) as high as 120°. This metal-oxide semiconductor shows a good long-term durability and excellent photocatalytic ability for the removal of salad oil under UV light irradiation. The hydrophobicity can be regenerated after contamination with salad oil due to the photocatalytic activity. In addition, this CeO 2 nanomaterial presents good repellence to hot water droplets. [ABSTRACT FROM AUTHOR]

A novel and green route for vapor-phase synthesis of 2- and 4-methylquinoline was provided in this work, in which lactic acid as one of the reactants was for the first time employed. Various influencing factors, including types of catalysts, reaction temperature and stability of catalyst were investigated systematically. The results showed that a 67.6% total yield of quinolines was obtained over the HBeta catalyst. The characterization by using BET, NH 3 -TPD and pyridine-IR techniques revealed that strong Brønsted acid sites are favorable for generation of 2- and 4-methylquinoline whereas Lewis acid sites could increase the proportion of 4-methylquinoline in target products. Besides, a feasible reaction pathway to synthesize 2- and 4-methylquinoline was proposed on the basis of the reaction products. [ABSTRACT FROM AUTHOR]

Abstract: The dynamic structural change of graphite during the electrochemical lithium intercalation at 1/3C was identified by an in situ high energy synchrotron XRD. Thanks to the fast data collecting detector and high energy X-ray beam of this characterization technique, the detailed structure change of graphite was monitored. Under a high current density, the voltage plateaus in discharge curve and superlattice peaks in XRD patterns were not observed. These results indicated that the dynamic lithium intercalation behavior was remarkably different from that described by the classical staging mechanism. Instead, a Li-riched phase as well as a series of intermediate phases for the x value in Li x C6 being larger than 0.5 were identified. This dynamic phenomenon was considered to be synergistically affected by the driving force of the intercalation reaction, van der Waals force between graphene layers and repulsive interaction between the intercalated Li specie. Basing on the experimental results, a dynamic mechanism was proposed. [Copyright &y& Elsevier]

A facile and solvent-free microwave-assisted approach to quinoline was developed by utilizing both acrolein diethyl acetal and aniline as reagents, firstly employing Ni/Beta zeolite as mild, ecofriendly and low-cost solid catalyst. As high as 83% yield of quinoline was quickly achieved at a short microwave time. The results indicated that the effect of Ni on Beta zeolite not only significantly promoted conversion of acrolein diethyl acetal to effective intermediate but also dramatically accelerated dehydrogenation rate of tetrahydroquinoline/dihydroquinoline to quinoline. [ABSTRACT FROM AUTHOR]

A Ni-based catalyst modified with copper and vanadium (5Cu–20V/30Ni/SiO2) was synthesized and employed in the hydrogenation of 3-hydroxypropanal (3-HPA) to 1,3-propanediol (1,3-PDO). Catalysts were systematically characterized via XRD, TEM, HRTEM, SAED, H2-TPD, N2 physisorption, H2-TPR, and XPS. It was indicated that the addition of Cu and V not only promoted the reduction of Ni2+ species and the generation of active hydrogen species, but also increased the dispersion of Ni species and the interaction between Ni particles and SiO2. The catalytic performance evaluation showed that the (5Cu–20V/30Ni/SiO2) could provide the largest yield of 1,3-PDO (above 76.8%) and highest TOF (4.32 × 103 s−1). The structure–activity relationship was clarified according to the characterization results. The optimized reaction conditions over the 5Cu–20V/30Ni/SiO2 catalyst were obtained as the reaction temperature of 80 °C, a H2 pressure of 2.0 MPa (H2), and an LHSV of 0.4 h−1. The employment of non-noble metals, the relatively low pressure of H2, and the relatively high yield of 1,3-PDO make 5Cu–20V/30Ni/SiO2 an efficient and economic catalyst that may have potential applications in industry. [ABSTRACT FROM AUTHOR]

Super-hydrophobic Co 3 O 4 -loaded nickel foam with two different morphologies were successfully prepared via a novel and simple method. The nano-flower and nano-flake structure was respectively generated on the surface of commercial nickel foam surface via hydrothermal treatment and then was modified with the perfluorinated alkyl silane reagent (PFAS). The samples were characterized by X-ray spectroscopy (XRD), Fourier transform infrared spectrometer (FT-IR), scanning electron microscopy (SEM), N 2 -physorption and water contact angle (WCA) meter. The results showed the Co 3 O 4 -loaded nickel foam possessed well super-hydrophobic and excellent corrosion-resistant properties after immersed in NaCl solution (3.5 wt.%), hydrochloric acid solution (pH = 1) and sodium hydroxide solution (pH = 14) each for 7 days in sequence. The water contact angle (WCA) of the corroded samples can reach 155°, and CAH (slide angle) are < 3°. Accordingly, it was a good method for the preparation of corrosion-resistant super-hydrophobic Co 3 O 4 -loaded nickel foam. [ABSTRACT FROM AUTHOR]

Highlights: [•] Dehydro-aromatization of 1,2-cyclohexanediol on Na2SO4 doped Ni/HZSM-5 catalysts. [•] The Ni loading was studied. [•] The role of Na2SO4 as a promoter of catalyst was studied. [•] The reaction mechanism was studied. [Copyright &y& Elsevier]

A novelmethod for the synthesis of high-performanced titaniumsilicalite-1 (TS-1) zeolite at a very low usage of tetrapropylammoniumhydroxide (TPAOH) was developed in this work. The method involveda temperature-programmed hydrothermal crystallization (TPHC) of abatch with a TPAOH/SiO2molar ratio of as low as 0.05,being 5 times smaller than that employed in the conventional synthesis,in which the TPAOH was entirely provided by a TS-1 precursor sol.The characterizations of X-ray diffraction (XRD), Fourier transforminfrared spectroscopy (FT-IR), diffuse reflectance ultraviolet–visiblespectroscopy (DR UV–vis), and scanning electron microscopy(SEM) indicated that the TS-1 synthesized via the novel method possesseda uniform crystal size of ∼0.3 μm, a very high crystallinityand a considerably large content of framework Ti (2.33 mol %). TheTS-1 had been employed as the catalyst for the ammoximation of cyclohexanone,of which the influencing factors were systematically investigated.It was shown that the TS-1 synthesized via the novel method possesseda very high performance, which is even better than for those synthesizedvia the conventional method both in this work and in the literaturework. [ABSTRACT FROM AUTHOR]

A large amount of uranium-containing wastewater is produced by the nuclear industry, which causes harm to human health and the environment. Goethite (α-FeOOH) is highly insoluble in water and has a net positive surface charge, making it an effective sorbent for metal–anion complexes in aqueous solutions. In this study, goethite (α-FeOOH) and Fe2+-modified magnetic goethite (M-α-FeOOH) were prepared using an easy one-pot chemical precipitation method and used to remove uranium from solution. The adsorbents were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), BET surface area analysis, fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometry (VSM). When Fe2+ partially substitutes for Fe3+, the material is magnetic, has a larger specific surface area and can be rapidly separated in a magnetic field. The uranium adsorption performance of M-α-FeOOH was substantially better than that of α-FeOOH, and its maximum adsorption capacity increased by 46.09%. The data fitted well with the quasi-second order kinetic model and the Langmuir isothermal adsorption model. According to the results of this study, the increase in the uranium removal performance of M-α-FeOOH was attributed to its higher specific surface area, better dispersion, and larger quantity of activated adsorption sites. These results, along with its low-cost, environmentally friendly, and facile synthesis, reveal M-α-FeOOH is a promising material for uranium capture. [Display omitted] • Fe2+ ​modification increased the specific surface area of goethite. • M-α-FeOOH achieved rapid solid–liquid separation under a magnetic field. • The uranium adsorption performance of M-α-FeOOH was markedly better, and its maximum adsorption capacity increased by 46.09%. • The adsorption of uranium and interaction were mainly related to coordination. [ABSTRACT FROM AUTHOR]