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Pd-based catalysts have been widely used in alkaline fuel cells. However, up to now, the effects of oxidation treatment of Pd-based catalysts on their application in alkaline fuel cells have been rarely reported. In this paper, PdCo nano-metal catalyst was prepared by calcination-oxidation treatment. It was found that the mass specific activity and area specific activity of the resulting PdO-Co3O4 nano-composite for electrocatalytic oxidation of ethylene glycol in alkaline solution were 3.8 and 2.4 times that of commercial Pt/C, respectively. Compared with PdCo nanometals, the mass specific activity and area specific activity of the PdO-Co3O4 nanocomposite for the electrocatalytic oxidation of ethylene glycol in the alkaline solution increased by 1.6 and 1.2 times, respectively. The experimental and calculated results showed that the surface morphology and active center of the catalyst changed after calcination and oxidation treatment. The adsorption energies of O2 and OH on the Co doped PdO (101) surface decreased, which was beneficial to stabilize the intermediate C2H4OHO*. As a result, the energy barrier for the O−H dissociation on the Co-doped surface was reduced. The strong binding of Co doped PdO (101) with ethylene glycol and its intermediate species led to different electrochemical kinetics and reaction path to produce excellent electric catalytic activity. The synergistic effect of PdO and Co3O4 significantly enhanced the interaction between active oxygen and catalyst surface, which not only facilitates the formation of superoxide species on the catalyst surface, but also improves the redox properties of the catalyst and promotes the electrocatalytic oxidation activity of ethylene glycol. The strategy of bi/multi-metallic oxidation proposed in this paper provides a general methodology for the construction of other catalysts.

In this study, multi-walled carbon nanotube (MWCNTs)-SiO2 composite adsorbents MWCNTs-SiO2-2, MWCNTs-SiO2-4, MWCNTs-SiO2-6 (CS2, CS4, CS6) with molar percentages of MWCNTs of 38%, 52%, and 66% were synthesized using the sol-gel method. The effects of the MWCNT content, temperature (30−60 °C), water vapor concentration (1%−5%), and the number of cycles on the adsorption capacity of toluene were studied, and an adsorption kinetics analysis was performed. The results showed that the adsorption capacity for toluene at 30−60 °C was AC (activated carbon) < CS2 < CS4 < CS6, and the adsorption capacity of CS6 to toluene was up to 50.28 mg/g. For every 10 °C increase in temperature, the penetration time decreased by 10−20 min, and the adsorption content decreased by 3.5% for every 1% increase in water vapor concentration. The phase with the fastest mass transfer rate of toluene could be described by the quasi-secondary adsorption kinetics model, in which intraparticle diffusion plays a major role. The mole percentage of MWCNTs ranged from 38% to 66%, the higher the content was, the easier it was to adsorb toluene. The functional group types of the MWCNTs-SiO2 adsorbent after regeneration did not change, and the adsorbent maintained good adsorption performance.

1,2-戊二醇（1,2-PeD）和1,5-戊二醇（1,5-PeD）是高附加值精细化学品，用途广泛。以糠醛及其衍生物为原料经催化加氢制备1,2-PeD和1,5-PeD是绿色的生产工艺，具有良好的应用前景和研究价值。本文系统综述了国内外以糠醛及其衍生物糠醇、四氢糠醇为原料制备1,2-PeD和1,5-PeD的研究现状，重点总结了应用于糠醛、糠醇和四氢糠醇催化加氢制备1,2-PeD和1,5-PeD的催化剂，从催化剂类型、不同催化体系辅助酸/碱催化反应机理、活性金属与掺杂过渡金属氧化物间的协同催化、掺杂过渡金属氧化物的酸性以及不同催化体系中催化剂的构效关系等方面进行了详细阐述，并在此基础上对该研究方向的发展趋势进行了展望。为开发新型、高效、稳定催化糠醛及其衍生物加氢催化剂体系提供了理论指导和有益的借鉴。

NiFe oxyhydroxide and hydroxide have been proven to be efficient and earth-abundant non-noble metal catalysts for the oxygen evolution reaction (OER). However, the fragile nature of these oxyhydroxides or hydroxides severely reduces the long-term stability and hinders the industrial applications. Meanwhile, the poor electrical conductivity of these materials also has seriously led to the higher overpotential when applying to the OER. Herien, a novel method using polyurethane (PU) sponge as electroplating was carried out to design NiFe alloy foam with different Fe content for OER. The physical properties of NiFe alloy foams were characterized by Scanning Electronic Microscopy (SEM), Energy Dispersive System (EDS) and X-Ray Diffraction (XRD), respectively, suggesting that the porous NiFe alloy is formed with uniform distribution of Ni and Fe. The OER performance was tested by Cyclic Voltammetry (CV), Linear Sweep Voltammetry (LSV), Electrochemical Impedance Spectroscopy (EIS), I-t, etc. The results showed that the doped Fe could significantly improve the conductivity and OER performance of Ni foam. The NiFe alloy foam with 30% Fe exhibited 292 mV overpotential at 10 mA/cm2 and the Tafel slope 126.12 mV/decade in alkaline solution with excellent long-term stability. Without any complex electrode preparation processes and binders, NiFe alloy foam is much convenient to use as anode of water splitting in alkaline media for industrial applications.

Electrocatalytic water splitting is one of the most prospective technology for hydrogen production. Molybdenum disulfide (MoS2), as one of the most promising non-noble metal electrocatalysts, suffers from the disadvantages of limited catalytic sites and weak conductivity which urgently needs to be further optimized. Herein, the C3N4-Ti4O7-MoS2 heterostructure is constructed through a simple hydrothermal strategy. The interfacial interaction between the active components leads to more exposed active sites, the redistribution of the surface charge, the optimization of the hydrogen adsorption kinetics and stability, which makes up the typical shortcomings of MoS2. The results indicate that the interface effect endows C3N4-Ti4O7-MoS2 catalyst with excellent electrocatalytic activity for hydrogen evolution reaction (HER). The current density of 50 mA/cm2 for HER is obtained at the overpotential of 300 mV, with the lower Tafel slope (54 mV/dec) and stable catalytic activity over 33 h, which is much better than that of the pure MoS2. This work indicates that the interface effect, as an effective strategy for rational design of MoS2-based electrocatalysts, is crucial to the future development of catalytic hydrogen production.

The effect of desulfurizer, modified TiO2 prepared by different methods on the NO emission from inferior coal burning and the adaptability of coal type were studied by using a tube furnace. The prepared Zr-TiO2 and the char were characterized by XRD, BET, SEM, XPS, TGA and XRF, and the mechanism of denitrification was explored. The results show that the addition of desulfurizer can promote NO emission. When the combustion temperature is 850℃, oxygen flow rate is 40 mL/min and the desulfurizer is MgO, the NO emission is the lowest as the catalyst of 5%Zr-TiO2 prepared by impregnation method is added, which is 51.0% lower than that with addition of pure TiO2 and 84.6% lower than that with pure coal under the same conditions. The catalyst 5% Zr-TiO2 can be applied to the coal with sulfur < 3% and ash < 30%, having a wide application range . The doping of Zr can inhibit the growth of grain, enhance the active component, increase the content of adsorbed oxygen, promote the transformation of the valence states of the elements, accelerate the devolatilization of volatiles, promote the combustion, increase the specific surface area of chars, and enhance the ability of heterogeneous reduction of chars.

β−O−4醚键是木质素结构中含量最丰富的单元间连接键型，研究高效断裂β−O−4的催化体系对木质素解聚制备单酚具有重要意义。本文以β−O−4型二聚体模型化合物为原料，结合GC-MS、GC-FID、HSQC NMR表征手段，考察碳负载金属催化剂、反应温度、时间、氢气初始压力等因素对二聚体β−O−4键的断键活性以及单体收率的影响。结果表明：NaOH与碳负载金属催化剂存在协同作用，可以增强β−O−4断键活性。其中，NaOH与Pd/C协同效果最佳，二聚体解聚单体产物从44.1%提高至83.4%。机理研究表明：NaOH协同Pd/C能有效抑制二聚体发生Cα羟基的脱除，显著提升二聚体β−O−4的断键选择性，从而提高了单体产物的收率。NaOH协同Pd/C催化体系对其他醚键（α−O−4）同样存在优异的断键能力。因此，在所做实验的最佳条件下，NaOH协同Pd/C催化体系能高效解聚碱木质素制备单酚化合物，单体产物收率高达37.5%，苯甲醇类选择性高达48.8%。

A series of metal phosphides including MoP, WP, CoP and NiP was prepared by temperature-programmed reduction with hydrogen from different phosphorus precursors. The effect of phosphorus precursor and feed H2/CO ratio on the catalytic performance of metal phosphides in the methanation was investigated. In comparison with diammonium hydrogen phosphate (DAP), phytic acid (PA) as a chelating agent can effectively disperse the metal precursor, reduce the reduction temperature, promote to form pure phosphide phase, and give the phosphide catalyst a higher surface area and a smaller particle size; as a result, the metal phosphides prepared with PA as a phosphorus precursor exhibit higher catalytic activity in methanation. In addition, the catalytic activity of various metal phosphides in methanation follows the sequence of MoP > WP > CoP > NiP. A high H2/CO ratio in the feed is favorable for the methanation over the phosphide catalysts; the selectivity to methane increases with an increase in the H2/CO ratio.

The chemical and mineralogical characteristics of fly ash from a municipal solid waste incineration (MSWI) in China and the influence of processing parameters on heavy metals removal during leaching were investigated in this work. The fly ash particles had complex surface structure with limited specific surface area. The alkali chloride and metal salts in MSWI fly ash showed evidently impact on leaching efficiency. Metal leachability was related to their properties and speciation in fly ash. Water-soluble salts such as KCl, NaCl and CaCl2 in fly ash were easily washed out. In this study, removal efficiency by water washing was achieved to 93.1% for Cl, 41.4% for Na, 48.5% for K and 24.8% for Ca, respectively. Mineralogical analysis also revealed change of fly ash mineral phases and specification distribution after water washing. Under liquid to solid ratio of 40∶1 L/kg and treatment time of 120 min, the leaching process achieved high dropping yields of toxicity characteristic leaching procedure (TCLP) concentrations for Cu, Zn Cd and Pb (80−100%), moderate dropping yields for As (30−80%) and relatively low dropping yields of Ni (< 30%). In addition, heavy metals such as Pb and Zn in fly ash with twice water washing treatment at a low liquid-solid ratio could reach lower TCLP concentrations. The result indicated that the combination process of twice water washing and one acid washing could significantly reduce the environmental risk of MSWI fly ash.

γ-Fe2O3催化剂具有催化性能高、成本低等优点，被认为是一种很有潜力的汞脱除材料。本文采用密度泛函理论（DFT）研究了在γ-Fe2O3表面HCl对Hg0的吸附和催化氧化的作用机制。构建了Hg0、HCl、HgCl和HgCl2在γ-Fe2O3(001)表面的吸附模型，分析了HCl对γ-Fe2O3表面催化氧化Hg0的作用机理，并通过反应路径的能量分布测定，研究了γ-Fe2O3表面Hg0的氧化过程。结果表明：Hg0倾向于化学吸附在γ-Fe2O3(001)表面Feoct位。HCl在催化剂表面进行解离吸附，形成吸附态Cl和羟基，从而促进Hg0的吸附。HgCl以分子形式化学吸附在γ-Fe2O3(001)上，并作为Hg0氧化过程的中间体。HgCl2倾向在γ-Fe2O3表面上的平行吸附。同时，HCl在γ-Fe2O3(001)上氧化Hg0遵循L-H机理，即化学吸附的Hg0与解离吸附的HCl反应，且HCl对Hg0的非均相氧化通过两步反应途径进行，即Hg0 (ads)→HgCl(ads)→HgCl2(ads)。

Waste gasification has the potential to contribute to China’s transition towards carbon neutrality and zero waste cities via the recirculation of waste as secondary carbon feedstock for the production of chemicals with lower/and or zero carbon footprint, green hydrogen with zero carbon footprint and CO2-neutral synthetic liquid fuels. With China’s significant coal gasification capacity and associated experiences and expertise, Coal-to-X could act as a bridge to Waste-to-X for carbon intensive sectors such as the waste management, chemical production and mobility sectors. To illustrate the opportunities in these areas, this article presented highlights from dynamic global developments in waste gasification, focusing on pioneering industrial developments in Germany between 1980’s−2000’s as well as current international developments. Lessons learnt from previous and current waste gasification project deployment are shared and enabled the identification of problems which will have to be addressed in the transition from coal gasification towards mono-waste gasification technologies. Additionally, a qualitative evaluation of gasification technologies pointed to the strengths and weaknesses of fixed-bed, fluidized-bed and entrained-flow gasification principles in their application for waste gasification.