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.     

乙醇/水体系负载型纳米Cu/Fe二元合金的合成、改性及其还原三氯乙烯的性能

在乙醇/水体系中采用KBH4液相还原法, 以石墨微粉为载体, Cu为复合金属, 通过两步法合成了具有球状团簇结构的负载型纳米Cu/Fe二元合金. 与单纯负载型纳米Fe0相比, 该复合材料对三氯乙烯(TCE)具有更高的还原脱氯性能, 纳米Fe0的质量浓度为10 g/L时, 5 h内能将10 mg/L的TCE完全去除. 将十六烷基三甲基溴化铵(CTAB)用于负载型纳米二元合金的表面改性, 改性后的材料对TCE的还原脱氯性能提高. 改性材料连续降解TCE 36 d, 10.2 mg/L TCE在7 h内即完全去除, 材料改性后不易氧化失活, 还原性能保持长期稳定.     

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)     

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.     

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。     

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。     

不同助剂掺杂的铬基催化剂的制备及其对乙烷氧化脱氢的催化性能

以硝酸盐作为前驱体,Al₂O₃为载体,采用等体积浸渍法制备了系列不同助剂（Mn, Co, Ce）及不同助剂含量（1%, 3%, 5%, 7%, 10%）掺杂的铬基催化剂,其结构经X-射线粉末衍射(XRD)、 H₂程序升温还原(H₂-TPR)和CO₂程序升温脱附（CO₂-TPD）表征。并考察了催化剂对乙烷氧化脱氢反应的催化性能。结果表明：添加Co助剂有利于活性组分铬的分散,10Cr₃Co/γ-Al₂O₃催化剂表现出最佳催化性能,在反应温度为650 ℃, V(CO₂) ：V(C₂H₆)=3 ：1,空速(GHSV)为3 600 mL·（g·h）^-1条件下,在该催化剂上乙烯产率为36.5%。     

DNA Induced FePt Bimetallic Nanoparticles on Reduced Graphene Oxide for Electrochemical Determination of Dopamine

FePt bimetallic nanoparticles were formed on reduced graphene oxide(rGO) with the help of double-stranded DNA(dsDNA) via a simple and universal route to obtain a FePt/DNA-rGO composite. The FePt nanoparticles with an average size of about 5 nm were well dispersed on rGO. FePt/DNA-rGO modified glassy carbon electrode(GCE) exhibited excellent electrocatalytic activity for the oxidation of dopamine(DA) with a detection limit of 100 nmol/L(S/N = 3). In addition, the FePt/DNA-rGO based electrochemical sensor showed an excellent selectivity for DA in the presence of ascorbic acid(AA), uric acid(UA) and other interference reagents. The as-prepared electrochemical biosensor shows great promise in the application of clinical diagnostics.     

Application of a novel bimetallic hydrogel based on iron and cobalt for the synergistic catalytic degradation of Congo Red dye

Herein, we developed a bimetallic (Fe and Co) polyacrylamide (PAM) hydrogel (FeCo@PAM) to investigate the synergistic catalytic degradation of Congo Red (CR) dye. The structure and the morphology of the FeCo@PAM hydrogel were analyzed using the Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectrometry (EDX). To study the chemical composition of our catalyst, the FTIR technique was applied. The SEM and EDX confirmed the presence of bimetallic ions in the PAM hydrogel. All critical parameters of the catalyst, that is, mass, dye concentration, H₂O₂ dose, temperature, and pH were investigated and optimized. The synergistic oxidative catalytic degradation of the CR dye using FeCo@PAM under the optimal conditions was calculated to be 96.45% (60 min), which was 11.26% (75 min) higher than that of Fe@PAM and 11.69% (75 min) higher than that of Co@PAM. For FeCo@PAM, not only the degradation percentage increased also the reaction time decrease was phenomenal. These experiments verified the synergistic oxidative degradation of the CR dye exhibited by the FeCo@PAM catalyst. The Kinetic isotherm studies were also studied to determine the CR degradation progression. Our FeCo@PAM catalyst also demonstrated to be highly recyclable, as high CR dye degradation was accomplished up to three consecutive cycles.