费托合成可将煤、天然气及生物质等各种非石油含碳资源通过合成气转化为各种油品和精细化学品.钴基催化剂因其水煤气变换反应活性低、费托反应活性高、碳链增长能力高的优良特点,在工业应用和相关科学研究上备受关注.钴基催化剂微观活性位的结构和费托反应过程中催化剂的表面吸附物等都会对F-T合成反应的产物分布以及催化性能有影响.本文分析总结了钴基费托合成催化剂中尺寸效应、晶相、晶面效应以及微观活性位点的研究进展,重点介绍了微观活性位的类型和微观活性位的表征方法/表面吸附行为,最后展望了钴基催化剂的未来发展方向和应用前景.

本研究用溶剂热法合成了三种暴露不同晶面的Co基催化剂,排除载体、助剂、晶粒尺寸等参数的影响,通过程序升温脱附、原位拉曼光谱、原位漫反射红外光谱等表征手段和化学瞬变反应技术,对不同晶面Co催化剂在费托反应过程中CO活化行为进行了研究.结果表明,CO的活化在不同晶面的Co基催化剂上具有结构敏感性.Co(10-11)晶面上CO以直接解离的方式进行活化,且CO解离生成的碳物种部分形成积炭,其余碳物种加氢生成CHx;Co(0001)晶面上CO以氢助解离的方式活化,大量解离为积炭,少量碳物种氢化为CHx;Co(11-20)晶面上CO直接解离,该催化剂上CO弱解离得到微量的积炭,其余碳物种在氢的存在下生成微量的CHx中间体.

稳定高效双金属催化剂的研究对于合成气直接合成乙醇具有重大意义,但也存在一定的挑战.本研究采用尿素辅助凝胶法和初湿浸渍法,制备了系列RhCu/P25双金属催化剂,并进行合成气直接制乙醇性能研究.研究表明,Rh改性的Cu基催化剂可以有效促进乙醇的生成,然而Rh和Cu活性位点之间紧密接触时,反应产物以甲烷和甲醇为主,乙醇含量甚微.RhCu/P25双金属催化剂反应性能的减弱与Rh和Cu活性位点上CO分子吸附受到抑制相关.当采用物理混合的方式增大Rh和Cu活性位点的空间距离时,CO分子的吸附明显增强,催化活性以及乙醇选择性提高.

Nano magnesium oxide has wide applications, and MgO with (111) facets has wider potential applications than MgO with (100) facets (e.g., in catalysis and adsorption). However, nano MgO with (111) polar faces has not been studied throughly, so the preparation of nano-octahedral MgO (N-O-MgO) with eight exposed (111) facets remains a great challenge. Herein, we successfully synthesised N-O-MgO via an effective solvothermal-solid-decomposition method and studied its adsorption performance. The obtained N-O-MgO showed excellent performance (229.36 mg g-1) for methyl orange (MO). The adsorption follows the pseudo-second-order kinetic equation and the Langmuir isotherm model. The dimensionless parameter R L (0.042) and Gibbs free energy ΔG (-6.538 kJ mol-1) revealed that the adsorption of MO on N-O-MgO was a spontaneous and feasible process. The adsorption of MO and methyl blue (MB) on N-O-MgO were studied to determine the adsorption sites. Based on these experiments and analysis, it was determined that the adsorption sites were magnesium ions and the adsorption mechanism was proposed to describe the adsorption process.

A sample preparation method for the extraction of bisphenol A (BPA) and tetrabromobisphenol A (TBBPA), potential endocrine-disrupting chemicals common in manufacturing, from environmental water samples was established by means of molecular-complex-based liquid-liquid microextraction coupled to high-performance liquid chromatography with diode array and mass spectrometric detection. In this method, tributyl phosphate acts as an extractant of BPA and TBBPA via hydrogen bond interactions. Additionally, no dispersants are needed. Attenuated total reflection Fourier transform infrared spectroscopy provides robust evidence for the formation of hydrogen bonds between the extractant and phenols in the molecular complexes, which supports the experimental results. Under optimised conditions, calibration plots were linear in the range of 0.05-2 mu g mL(-1) and detection limits ranged from 0.16 to 0.23 ng mL(-1). The relative standard deviations of intra-day and inter-day repeatability were in the ranges of 3.5-4.9% and 5.1-6.8%, respectively, and recoveries ranged from 84.5 to 105.6%. The method we developed has been successfully employed in the measurement of BPA and TBBPA in four aqueous environmental samples. (C) 2020 Published by Elsevier B.V.

A method prior to using high-performance liquid chromatography (HPLC), named phase transfer catalyst-assisted reversed-phase dispersive liquid-liquid microextraction (PTC-RP-DLLME), was developed for the rapid determination of organic acids in Fischer-Tropsch synthesis (FTS) oil products. This method used sodium hydroxide solution and tetrabutylammonium bromide (TBAB) as an extractant and a disperser respectively, in which the TBAB promoted the dispersion of aqueous NaOH solutions in the organic product, and acted as a hydrogen bond receptor to enhance the extraction of organic acids via hydrogen bond interactions. Under the optimized conditions, the calibration curves in the range of 0.1-30 mu g mL(-1) showed correlation coefficients (r) of 0.998-0.999. Detection limits (S/N = 3) were ranged from 1.0 to 3.5 ng mL(-1). The relative standard deviations of intra-day and inter-day repeatability were in the range of 2.9-5.8 % and 4.1-6.7%, respectively. The recoveries ranged from 85.4% to 105.9%. This developed method was employed for the analysis of organic acids in 6 types of oil products. This work provides an efficient and rapid pretreatment method for acid concentration prior to HPLC, and therefore saves time and cost for the quantitative analysis of FTS oil products. Moreover, precise analysis by application of this method is fairly beneficial to the FT catalyst improvement and industrial equipment material selection, and is rather significant for the proper design of the downstream processing/purification system.

For simultaneous analysis of four fat-soluble tocopherols (α-, β-, γ-, and δ-) in edible oils, an efficient and green method using deep eutectic solvent-based liquid-phase microextraction (DES-LPME) coupled with reversed-phase high-performance liquid chromatography (RP-HPLC) was developed. The DESs formed by different quaternary ammonium salts and ethanol were used as the extractants. Tetrabutylammonium chloride (TBAC)-ethanol DES at a molar ratio of 1:2 achieved the best extraction efficiency. Under the optimized conditions, the detection limits were in the range of 2.1–3.0 ng mL−1. The intra-day and inter-day repeatability were in the ranges of 3.9–5.3% and 4.8–7.1%, respectively, and the recoveries for the real samples varied from 80.7% to 105.4%. The developed method was successfully employed for the determination of all four tocopherol homologues with an RP-HPLC system containing a COSMOSIL π-NAP column in five edible oils collected locally.

This paper reports adsorption behaviors of monocyclic aromatics from water onto different pore-size activated carbons and HNO3-modified activated carbon fiber felt, and modelling of experimental data by the Langmuir, the Freundlich, the Dubinin-Radushkevich and the Temkin isotherms. To study the adsorption mechanism, the maximum uptakes of compounds by activated carbons in the Langmuir model were correlated with the structure of activated carbons. The results show that the Langmuir isotherm is superior to other isotherms and the Langmuir model can approximately describe adsorption behaviors of activated carbons for aniline, phenol, and pyridine. For high-concentration adsorption, activated carbon's micropore volume has a positive effect on adsorption capacity of compounds, and micropore filling mainly happens. The uptake of aniline and phenol by activated carbon is obviously higher than that pyridine, which is ascribed to their low solubility. The surface acidic groups (mainly oxygen-containing groups) of activated carbon fiber felt obviously decrease adsorption capacity for aromatics due to a decrease in dispersion interaction between activated carbon's surface and aromatics. The results show that in order to effectively remove high-concentration aromatics from water, effects of micropore vlome and surface acidic groups of activated carbons need to be considered, compared and analyzed, and micropore volume of activated carbon should usually be given priority to.

通过扫描电子显微镜、X射线衍射仪、N 2 吸附分析仪及Boehm滴定法获得ZnCl 2 、KOH和HNO 3 化学处理对高纯多壁碳纳米管的结构和表面含氧官能团的影响,通过批处理实验考察吸附条件（吸附时间、初始浓度、温度）对处理前后的碳纳米管吸附苯酚行为的影响,并采用准一级、准二级、Evolich动力学模型和热力学方程拟合其吸附数据,分析其动力学行为、热力学行为和吸附机理。结果表明,虽然ZnCl 2 、KOH和HNO 3 化学处理法均未对碳纳米管BET比表面积产生显著影响,但会影响其表面化学性质（即,对于ZnCl 2 和KOH化学处理降低表面羧基、内酯基含量和增大碱性官能团量,而对于HNO 3 化学处理可以增大表面羧基、内酯基含量,而碱性官能团略有增加）;改性处理影响碳纳米管去除苯酚效率:由于ZnCl 2 和KOH改性处理降低碳纳米管表面羧基量,故其提高了苯酚去除率,而HNO 3 处理则略减小碳纳米管的苯酚去除率,可能是由于碳纳米管结构和表面化学性质共同影响所致;碳纳米管的苯酚去除率均随苯酚溶液初始浓度的增大而减小;高温不利于吸附;热力学研究发现碳纳米管吸附苯酚过程是自发的和放热的,属于物理吸附;动力学研究表明,吸附过程符合准二级动力学方程。通过ZnCl 2 和KOH化学处理,可以显著提高碳纳米管对苯酚的吸附性能。

A sample preparation method for the extraction of bisphenol A (BPA) from edible oils was established via simple, green, and sensitive deep eutectic solvent-based liquid-liquid microextraction (DES-LLME) before high-performance liquid chromatography (HPLC) with diode array detector (DAD). The deep eutectic solvent (DES) formed by tetrabutylammonium bromide (TBAB) and methanol was acted as the extractant All parameters in the DES-LLME step, including the type and volume of extractants, the extraction time, and centrifugation time, were investigated and optimized. The application of hydrophilic DES in oils expands the selection of LLME extractants. Under the optimized conditions, the calibration curves in the range of 10-500 ng g(-1) with a correlation coefficient of r> 0.999, and the detection limit was 0.8 ng g(-1). The relative standard deviations of intra-day and inter-day repeatability were 4.3% and 62%, respectively, and the recoveries varied between 88.7% and 973%. This developed method was successfully employed for measuring BPA in 6 edible oil samples. (C) 2020 Elsevier B.V. All rights reserved.

Multi-structured Ag/MnO2-cordierite molded catalysts were prepared by hydrothermal method and applied to the catalytic oxidation of VOCs. Catalytic activities of Ag/MnO2-cordierite were evaluated by 1000 ppm of toluene, ethyl acetate and chlorobenzene degradation respectively at the air atmosphere, and their physicochemical properties were characterized through multiple techniques containing XRD, SEM, TEM, H2-TPR and XPS. It is found that nanorod Ag/MnO2-cordierite molded catalyst showed prominent catalytic activity for VOCs decomposition and the T90 for toluene, ethyl acetate and chlorobenzene are 275 °C, 217 °C and 385 °C respectively under the space velocity of 10,000 h−1. High valence manganese oxide, more active lattice oxygen proportion and superior low-temperature reducibility were the great contributors to the high activity of the catalyst with nanorod morphology. Studies of space velocity and catalytic stability over nanorod Ag/MnO2-cordierite molded catalyst have confirmed the good catalytic performance, excellent mechanical strength and satisfied anti-toxicity to Cl at higher space velocity, which indicates that this molded catalyst have promise for industrial application.

Four different ionic liquids (ILs) were used to identify their extraction properties on high-sulfur bituminous coal. And the effect of ILs pretreatment on pyrolysis characteristic was investigated in a fixed-bed reactor. The imidazolium-based ILs used namely: 1-butyl-3-methyl-imidazolium chloride ([Bmim]Cl), 1-butyl-3-methyl-imidazolium bromide ([Bmim]Br), 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4), 1-butyl-3-methyl-imidazolium tetrafluoroborate ([Bmim]BF4). All the selected ILs exhibited extraordinary extraction ability for oxygen-containing compounds, mainly furans and ethers. Among them, [Bmim]Cl got the highest extraction yields of 20.82% and performed selective extraction ability for sulfur-containing compounds with a relative content of 5.10% in light oils. Compared with pyridine pretreated coal (R-PY), the yields of CO and CO2 in pyrolysis gas showed increase trend when coal pretreated by ILs (R-ILs). The relative contents of tricyclic and larger PAHs, sulfur-containing compounds, and oxygen-containing compounds in tar from pyrolysis of [Bmim]Cl and [Bmim] Br treated coal increased significantly than R-PY tar, while phenols got decreased. High carbon number components from R-ILs tar reduced dramatically compared with R-PY tar, which was conducive to the upgrading of tar, after pretreated with ILs, the sulfur content was reduced. The crosslinks between coal macromolecules structure were destroyed after pretreated by ILs, and the pyrolysis products distribution had evident change. The oil phase yield got a substantial increase while [Bmim]Cl obtained highest oil yield of 24.89%.

This work consists of preparation of iron-doping activated carbon (Fe/AC) by pore impregnation, the effects of Fe(NO3)(3) treatment on the physical/chemical properties of activated carbon (AC), the effects of main influential experiment parameters such as contact time, initial phenol concentration, temperature and pH on adsorption of phenol onto AC and Fe/AC, the effects of various regeneration methods including thermal regeneration and dry catalytic oxidation on the adsorption capacity of AC and Fe/AC for phenol, the catalytic oxidation behaviors of phenol adsorbed over Fe/AC and the assessment of the adsorption capacity of Fe/AC for phenol in the adsorption-oxidation runs. The adsorbent-catalysts were characterized by liquid N-2 adsorption, scanning electronic micrograph, elemental analysis, Boehm titration, Fourier transform infrared spectroscopy and temperature-programmed desorption. To understand equilibrium adsorption, the adsorption data were analyzed by Langmuir, Freundlich, Dubinin-Radushkevich and Temkin models. To predict the nature of adsorption, the thermodynamic parameters (Delta G degrees, Delta H degrees and Delta S degrees) were calculated and analyzed. The results show that the Fe(NO3)(3) treatment increases obviously the oxygenated acidic surface groups of AC. The equilibrium capacity of Fe/ACs for high-concentration phenol is lower than that AC. More surface acidic groups of Fe/AC decrease the equilibrium uptake of phenol and the order of the phenol uptake by the adsorbent- catalysts follows AC > Fe1/AC > Fe5/AC mainly due to an increase in competition of water adsorption derived from the increase in surface hydrophilic property of AC or more water clusters formed in adsorption processes. Langmuir model can better describe adsorption of phenol on AC and low mass-fraction Fe-doping AC, whereas Freundlich model meets with that high mass-fraction Fe-doping AC. Adsorption of phenol on AC and Fe/AC is spontaneous and exothermic. Compared with original AC, Fe/AC has high catalytic oxidation performance of phenol on Fe/AC. Fe/AC shows higher phenol adsorption in successive runs. For pollution-free treatment, the dry catalytic oxidation of phenol is significantly superior to thermal regeneration. The experimental results indicate that dual functional Fe/AC can be used to effectively remove phenol from wastewater.

Clarifying the facet-dependent activity of Co3O4 towards C3H8 combustion is of great importance to have a deep understanding of reaction mechanism and develop highly active Co3O4 based catalysts for light hydrocarbon combustion. In this work, four different Co3O4 nanocatalysts which dominantly exposed {100}, {111}, {110} and {112} facets, respectively, were synthesized via hydrothermal method and further tested in C3H8 combustion. The catalytic activity of different crystal planes varied as the order of {111}>{100}>{110}>{112}. The Co3O4 catalyst with {111} facets exhibited the best catalytic performance with T-50 and T-90 as low as 209 and 239 degrees C, respectively. DRIFT and DFT calculations revealed that the facile activation of C-H bond on Co3O4 {111} planes is responsible for the high activity. Moreover, the higher activity of lattice oxygens and easy activation of gas phase oxygen could also contribute to the excellent catalytic performance.

Multistage mesoporous magnesium oxide prepared by a simple hydrothermal method has an ideal particle size, channel distribution, active crystal face, good catalytic activity and regeneration ability.

In the present study, three kinds of copper/titania-silica mixed oxides (Cu/TS) catalysts were prepared using copper chloride, copper nitrate, and copper acetate as copper precursors by the sol-gel method. The catalytic performance was tested in the vapor phase carbonylation of methanol free of halide. The characterization results showed that the interaction between copper and support was the strongest on the 10Cu/TS (Cl) catalyst, leading to the highest copper dispersion and the most surface Cu+ species. As a result, the 10Cu/TS (Cl) catalyst obtained the largest absorption capacity of CO and the maximum amount of Lewis acid sites. The catalytic performance results showed that the space time yield (STY) of methyl acetate (MA) was positively correlated with the content of surface Cu+ species and the specific surface area of the Cu+ cations (SCu(I)). Therefore, the 10Cu/TS (Cl) catalyst obtained the highest STYMA of 1.619 mol/h.kgcat. Moreover, the STYMA per Cu+ site was inversely proportional to the copper particle size, indicating that the carbonylation of methanol to MA is a structure-sensitive reaction. And the methanol conversion was positively correlated with the amount of surface acid sites. Furthermore, the active sites for the synthesis of methyl formate and dimethyl ether were also studied.

Mesoporous CuO/MgO catalyst was synthesized by hydrothermal homogeneous precipitation using urea as precipitating reagent. The CuO/MgO catalyst was characterized by BET-N-2, X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), transition electron microscopy (TEM), Raman spectra and thermogravimetric analysis (TG). The results indicate that CuO/MgO catalyst possesses extremely fine dispersion of Cu nanoparticles (NPs) with a high specific surface area of 232 m(2)/g and pore sizes of 6.5 nm. The mesoporous CuO/MgO exhibits excellent catalytic activity for the formaldehyde reaction of acetylene.

The nature of high-silica H-Y acid sites in dimethoxymethane carbonylation is investigated by NH3 poisoning with a combination of reaction results, diffuse reflection infrared Fourier transform spectra, and NH3 temperature-programmed desorption. After NH3 poisoning of H-Y, ammonia desorption of zeolites NH4-Y was conducted at different temperatures to obtain catalysts HNH4-Y that gradually exposed different acid sites. The zeolites thus produced catalyzed dimethoxymethane carbonylation with a linear dependence of the conversion on the ammonia desorption temperature before the plateau stage. It was observed that strong Bronsted acids in zeolite Y catalyzed the reaction more selectively toward the main product methyl methoxyacetate, and weak Bronsted acids catalyzed the reaction more selectively toward the byproduct methyl formate. Furthermore, the turnover frequency of Bronsted acids varied significantly among the Bronsted acids and decreased with acid strength. This finding suggested that only 10.1-18.3% of the total Al in zeolite Y with Si/Al ratios of 15, 30, and 40 contributed to the total framework Bronsted acids.