Synergistic Catalytic Performance of Toluene Degradation Based on Non-Thermal Plasma and Mn/Ce-Based Bimetal-Organic Frameworks

A series of Mn/Ce-based bimetal-organic frameworks, recorded as MCDx (x = 1, 2, 4, 6), were prepared by a solvothermal synthesis method to explore their effects and performance in the synergistic catalysis of toluene under the irradiation of non-thermal plasma. The catalytic properties of different manganese loadings in MCDx for degradation of toluene were investigated. The microphysical structures of the material were analyzed by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The results showed that a MCDx coupling with non-thermal plasma can greatly improve the degradation efficiency, the energy efficiency and the CO₂ selectivity, and could also significantly reduce the generation of O₃ in the by-products. Among the test samples, MCD6 with Mn:Ce = 6:1 (molar ratio) showed the best catalytic performance and stability, exhibited toluene catalytic efficiency 95.2%, CO₂ selectivity 84.2% and energy efficiency 5.99 g/kWh, and reduced O₃ emission concentration 81.6%. This research provides a reference for the development and application of synergistic catalysis based on bimetal-organic frameworks and non-thermal plasma in the reduction of industrial volatile organic compounds.     

Capture-bonding Super Assembly of Nanoscale Dispersed Bimetal on Uniform CeO2 Nanorod for the Toluene Oxidation

Elimination of VOCs by catalytic oxidation is an important technology. Here, a general synergistic capture-bonding superassembly strategy was proposed to obtain the nanoscale dispersed 5.8% PtFe₃−CeO₂ catalyst, which showed a high toluene oxidation activity (T₁₀₀=226 °C), excellent catalytic stability (125 h, >99.5%) and a good water resistance ability (70 h, >99.5%). Through the detailed XPS analysis, oxygen cycle experiment, hydrogen reduction experiment, and in-situ DRIFT experiment, we could deduce that PtFe₃−CeO₂ had two reaction pathways. The surface adsorbed oxygen resulting from PtFe₃ nanoparticles played a dominant role, due to the fast cycling between the surface adsorbed oxygen and oxygen vacancy. In contrast, the lattice oxygen resulting from CeO₂ nanorods played an important role due to the relationship between the toluene oxidation activity and the metal-oxygen bonding energy. Furthermore, DFT simulation verified Pt sites were the dominant reaction active sites during this reaction.     

纳米Fe/Ni双金属的制备及其对水中2,4-二氯酚的还原效果

 采用液相还原法制备了纳米Fe/Ni双金属材料,分析了FeCl₂浓度、n（Ni）/n（Fe）和n（NaBH₄）/n（FeCl₂）物质的量之比对制得的Fe/Ni双金属还原水中2,4-二氯酚（2,4-DCP）效果的影响,明确了Fe/Ni对2,4-DCP的还原脱氯途径。结果表明：在FeCl₂浓度为3 mol/L、n（Ni）/n（Fe）=4%,n（NaBH₄）/n（FeCl₂）=1的条件下制备的Fe/Ni双金属对2,4-DCP的去除率接近100%,且其中95%被还原成苯酚。纳米Fe/Ni为球形颗粒,粒径约为50 nm,在自身磁力作用下相互链接为枝状,又通过静电稳定作用分散聚集,形成海绵状多孔结构,BET比表面积为44.8 m²/g。纳米Fe/Ni还原2,4-DCP的途径主要是苯环上的2个C-Cl键依次被加氢还原,先脱去一个氯生成2-氯酚或4-氯酚,再进一步脱氯转化为稳态的苯酚。     

异丁烯氢甲酰化用负载型PPh3-Rh-Co/SiO2配合物高效催化剂

制备了SiO2担载的Rh-Co双金属配合物催化剂,用FT-IR、TPR和TPD等手段对催化剂进行了表征,并用异丁烯氢甲酰化反应考察了催化剂的性能.结果表明,Co和Rh之间存在协同效应,这种协同效应可以促进二者在载体表面的分散;可以促进催化活性物种前驱物数量的增加,从而提高催化剂的催化性能;氢甲酰化反应产物中没有副产物特戊醛的生成;经过研究和优化,高效催化剂在2.5 MPa反应压力下5 b内异戊醛的平均产率可达1257.5 mol/mol-Rh·h.     

液-固相轧制复合法生产含硅中锡铝合金/钢复合轴瓦带的组织和界面

采用液固相轧制法可以稳定、连续生产AlSn8Si2.5Pb2Cu0.8Cr0.2覆钢双层轴瓦带·通过金相和EPMA照片显示其组织与铸造组织相似,但含有大量致密细小、发达的柱状枝晶,组织内Si、Sn等元素分布均匀·由于复合界面结合强度较高,撕开后钢表面有大量的铝块,其复合机理主要是由于钢、铝充分润湿,高温和较大的轧制力使钢表面污染层、氧化层变薄,形成牢固的冶金结合所致·     

ZrO2改性Co-Ru/γ-Al2O3催化剂F-T合成的本征动力学

根据费-托(F-T)合成的表面碳化物机理,推导出合成气反应的8个动力学模型.利用固定床微分反应器对ZrO2改性Co-Ru/γ-Al2O3催化剂在473 K和458～498 K下的F-T合成动力学进行了研究.结果表明:473 K时,H2完全解离,吸附态CO加氢生成甲酰(HCO),HCO加氢生成表面C,同时氧以水的形式脱除(模型6),实验结果最吻合.在473K时,反应速率表达式为:-dNCO/dw=kpCOp1/2H2/(1 1.499p1/2H2 1.609pCO 2.541p-1/2H2pCO)2,k为99.83 mmol/(h·g·MPa1.5).通过实验数据对模型6的非线性回归,对反应活化能、吸附活化能等进行了估算,活化能为68.34 kJ/mol.     

基于压应力的新型温度计设计

利用应变式压力传感器测量由全桥式双金属片因热胀冷缩产生的形变,获得温度调制的电压信号,并通过A/D转换芯片将信号传入STM32F407ZGT6核心控制器,利用TFT屏幕来显示所测温度,获得了一种低成本、低功耗的新型数字温度计。     

Ru-Ni/C催化剂在碱性介质中的析氢性能研究

氢气的高效生产和利用对构建清洁低碳的能源体系至关重要, 碱性电解水制氢是目前我国应用最多的制氢技术,但也存在能耗较高的难题。因此迫切需要寻找低成本、高性能的电催化剂用于析氢反应（HER）提高水分解效率。本工作采用沉积沉淀法合成了双金属负载型Ru-Ni/C催化剂,用透射电子显微镜（TEM）和X射线衍射（XRD）对催化剂的形貌和结构进行了表征。用线性扫描伏安法（LSV）、电化学阻抗谱（EIS）等测试了HER性能。结果显示炭载体上RuNi双金属均匀分散,在电流密度为10 mA?cm-2时过电位仅为34.4 mV且稳定性良好,Tafel斜率仅为60.33 mV?dec-1,比商用Pt/C还小。表明Ru-Ni/C催化剂展现出了优异的HER电催化活性和稳定性,RuNi双金属之间的协同效应很大程度上促进了催化剂的催化性能,该研究为发展高效的碱性电解水制氢阴极催化剂提供了新思路。     

Dehalogenation of Aryl Halides Catalyzed by Montmorillonite Immobilized Bimetal Catalyst in Aqueous System

A novel bisupported bimetal catalyst PVP-PdCl2-FeSO4/Al-Mont-PEG600 was prepared by immobilization of PVP (poly (N-vinyl-2-pyrrolidone)) supported bimetallic catalyst using alumina pillared inartificial montmorillonite as the carrier. This catalyst has good dehalogenation activity and selectivity to aryl halides-o-chlorotoluene in aqueous system in the presence of phase transfer catalyst (PEG) and sodium formate as hydrogen source. The catalyst also shows good reusability.     

Hydroisomerization of n-heptane over bimetal-bearing H3PW12O40 catalysts supported on dealuminated USY zeolite

The bimetal-bearing (CePt or LaPt) 12-tungstophosphoric acid (H₃PW₁₂O₄₀ (PW)) catalysts supported on dealuminated USY zeolite (DUSY) were prepared by impregnation and characterized by XRD, BET, IR, and H₂-chemisorption. Their catalytic activities were tested in the hydroisomerization of n-heptane with a continuous atmospheric fixed-bed reactor. After the steam treatment combined with the acid leaching, as well as the supporting with PW and the bimetals, the DUSY support retains the Y zeolite porosity and the PW well keeps its Keggin structure in catalysts. The doping of Ce into the catalysts enhances the dispersion of Pt on the catalyst surface. The Pt-bearing PW catalysts doped with Ce or La, especially Ce, exhibit much higher catalytic activity and selectivity than the catalysts without dopants at lowered reaction temperatures. At the optimal reaction conditions, i.e., the reaction temperature of 250°C and WHSV of 1.4 h⁻¹, the catalyst with a Pt loading of 0.4%, PW loading of 10% and a molar ratio of Ce to Pt of 15:1 shows a conversion of n-heptane of 70.3% with a high selectivity for isomerization products of 94.1%. Supported by the Natural Science Foundation of China (Nos. 20306011 and 20476046), the Ph. D. Program Foundation of Chinese University (20040291002), and the Ph. D. innovation Program Foundation of Nanjing University of Technology (BSCX200506)