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关键词

催化剂 4

乳液 2

内禀尺度 2

双层辉光离子渗金属 2

吸附 2

地球物理 2

无氢渗碳 2

细水雾 2

&alpha 1

6G 1

CO2 加氢 1

GDM过滤技术 1

GPS数据 1

GPS浮标 1

H2S 1

K 助剂 1

MOF基催化剂 1

Mn 助剂 1

P4 1

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Synthesis of boron modified CoMo/Al

Hui Shang, Chong Guo, Pengfei Ye, Wenhui Zhang

《化学科学与工程前沿(英文)》 2021年 第15卷 第5期   页码 1088-1098 doi: 10.1007/s11705-020-1969-y

摘要: Catalytic hydrodesulfurization (HDS) technique is widely used for clean gasoline production. However, traditional HDS catalyst (CoMo/ -Al O ) exhibits high hydrogenation performance of olefins (HYDO), resulting in the loss of gasoline octane number. To achieve high HDS/HYDO ratio, the key issue is to reduce the interaction between active metals and the support, therefore, in this research, the modified CoMo/ -Al O catalysts with various boron amounts were investigated under traditional or microwave heating. The effects of preparing methods as well as boron amounts on the active phase, acidic properties and HDS catalytic activities were examined. Results show that the modification, especially under microwave treatment, can significantly weaken the interaction between the active component and the support by enlarging the surface area and pore diameter, and reducing the acidity of the support. As a result, the stacking numbers of MoS slabs were obviously improved by the modification and microwave treatment, contributing to higher edge/rim ratio, and resulting in higher HDS performance and selectivity to olefin.

关键词: CoMo catalyst     boron modification     surface acidity     microwave heating     selective hydrodesulfurization    

Abatement of mixed volatile organic compounds in a catalytic hybrid surface/packed-bed discharge plasma

Lianjie Guo, Nan Jiang, Jie Li, Kefeng Shang, Na Lu, Yan Wu

《环境科学与工程前沿(英文)》 2018年 第12卷 第2期 doi: 10.1007/s11783-018-1017-z

摘要: In this study, post plasma-catalysis degradation of mixed volatile organic compounds (benzene, toluene, and xylene) has been performed in a hybrid surface/packed-bed discharge plasma reactor with Ag-Ce/ g-Al O catalyst at room temperature. The effect of relative air humidity on mixed VOCs degradation has also been investigated in both plasma-only and PPC systems. In comparison to the plasma-only system, a significant improvement can be observed in the degradation performance of mixed VOCs in PPC system with Ag-Ce/ g-Al O catalyst. In PPC system, 68% benzene, 89% toluene, and 94% xylene were degraded at 800 J·L , respectively, which were 25%, 11%, and 9% higher than those in plasma-only system. This result can be attributed to the high catalytic activity of Ag-Ce/ g-Al O catalyst to effectively decompose O and lead to generating more reactive species which are capable of destructing the VOCs molecules completely. Moreover, the presence of Ag-Ce/ g-Al O catalyst in plasma significantly decreased the emission of discharge byproducts (NO and O ) and promoted the mineralization of mixed VOCs towards CO . Adding a small amount of water vapor into PPC system enhanced the degradation efficiencies of mixed VOCs, however, further increasing water vapor had a negative impact on the degradation efficiencies, which was primarily attributed to the quenching of energetic electrons by water vapor in plasma and the competitive adsorption of water vapor on the catalyst surface. Meanwhile, the catalysts before and after discharge were characterized by the Brunauer-Emment-Teller and X-ray photoelectron spectroscopy.

关键词: Mixed VOCs     HSPBD plasma reactor     Degradation     Catalyst     Relative humidity    

Synthesis, characterization and hydrotreating performance of supported tungsten phosphide catalysts

SUN Guida, LI Cuiqing, ZHOU Zhijun, LI Fengyan

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 155-164 doi: 10.1007/s11705-008-0038-8

摘要: Supported tungsten phosphide catalysts were prepared by temperature-programmed reduction of their precursors (supported phospho-tungstate catalysts) in H and characterized by X-ray diffraction (XRD), BET, temperature-programmed desorption of ammonia (NH-TPD) and X-ray photoelectron spectroscopy (XPS). The reduction-phosphiding processes of the precursors were investigated by thermogravimetry and differential thermal analysis (TG-DTA) and the suitable phosphiding temperatures were defined. The hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activities of the catalysts were tested by using thiophene, pyridine, dibenzothiophene, carbazole and diesel oil as the feedstock. The TiO, -AlO supports and the Ni, Co promoters could remarkably increase and stabilize active W species on the catalyst surface. A suitable amount of Ni (3%–5%), Co (5%–7%) and V (1%–3%) could increase dispersivity of the W species and the BET surface area of the WP/-AlO catalyst. The WP/-AlO catalyst possesses much higher thiophene HDS and carbazole HDN activities and the WP/TiO catalyst has much higher dibenzothiophene (DBT) HDS and pyridine HDN activities. The Ni, Co and V can obviously promote the HDS activity and inhibit the HDN activity of the WP/-AlO catalyst. The G-Ni5 catalyst possesses a much higher diesel oil HDS activity than the sulphided industrial NiW/-AlO catalyst. In general, a support or promoter in the WP/-AlO catalyst which can increase the amount and dispersivity of the active W species can promote its HDS and HDN activities.

关键词: tungsten phosphide     differential thermal     catalyst surface     industrial NiW/-AlO     general    

Modeling nanostructured catalyst layer in PEMFC and catalyst utilization

Jiejing ZHANG, Pengzhen CAO, Li XU, Yuxin WANG

《化学科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 297-302 doi: 10.1007/s11705-011-1201-1

摘要: A lattice model of the nanoscaled catalyst layer structure in proton exchange membrane fuel cells (PEMFC) was established by Monte Carlo method. The model takes into account all the four components in a typical PEMFC catalyst layer: platinum (Pt), carbon, ionomer and pore. The elemental voxels in the lattice were set fine enough so that each average sized Pt particulate in Pt/C catalyst can be represented. Catalyst utilization in the modeled catalyst layer was calculated by counting up the number of facets of Pt voxels where “three phase contact” are met. The effects of some factors, including porosity, ionomer content, Pt/C particle size and Pt weight percentage in the Pt/C catalyst, on catalyst utilization were investigated and discussed.

关键词: catalyst layer     PEM fuel cell     lattice model     Monte Carlo method     catalyst utilization    

Ni-Bi 助剂用于α-Fe2O3 Letter

党珂,王拓,李澄澄,张冀杰,刘珊珊,巩金龙

《工程(英文)》 2017年 第3卷 第3期   页码 285-289 doi: 10.1016/J.ENG.2017.03.005

摘要:

本文提出了镍-硼酸(Ni-Bi) 助催化剂负载于α 型三氧化二铁(Fe2O3) 具有提升表面动力学和钝化表面态的双重作用。Ni-Bi助剂的负载使Fe2O3 光电阳极的光电流起始电位产生230 mV 的负移,1.23 V(vs. RHE)下的光电流密度也提升了2.3 倍。Ni-Bi助剂层中的Bi 促进了产氧反应的脱质子步骤。

关键词: 镍-硼酸     &alpha     型三氧化二铁     产氧反应     助催化剂    

Oxidant or catalyst for oxidation?

Jianzhi Huang, Huichun Zhang

《环境科学与工程前沿(英文)》 2019年 第13卷 第5期 doi: 10.1007/s11783-019-1158-8

摘要: Manganese oxides (MnOx) have been demonstrated to be effective materials to activate Oxone (i.e., PMS) to degrade various contaminants. However, the contribution of direct oxidation by MnOx to the total contaminant degradation under acidic conditions was often neglected in the published work, which has resulted in different and even conflicting interpretations of the reaction mechanisms. Here, the role of MnOx (as both oxidants and catalysts) in the activation of Oxone was briefly discussed. The findings offered new insights into the reaction mechanisms in PMS-MnOx and provided a more accurate approach to examine contaminant degradation for water/wastewater treatment.

关键词: Peroxymonosulfate     Manganese oxides     Catalyst     Oxidant    

Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 146-150 doi: 10.1007/s11705-007-0027-3

摘要: The performance of the polymer electrolyte membrane fuel cell (PEMFC) is greatly controlled by the structure of the catalyst layer. Low catalyst utilization is still a significant obstacle to the commercialization of the PEMFC. In order to get a fundamental understanding of the electrode structure and to find the limiting factor in the low catalyst utilization, it is necessary to develop the mechanical model on the effect of catalyst layer structure on the catalyst utilization and the performance of the PEMFC. In this work, the structure of the catalyst layer is studied based on the lattice model with the Monte Carlo simulation. The model can predict the effects of some catalyst layer components, such as Pt/C catalyst, electrolyte and gas pores, on the utilization of the catalyst and the cell performance. The simulation result shows that the aggregation of conduction grains can greatly affect the degree of catalyst utilization. The better the dispersion of the conduction grains, the larger the total effective area of the catalyst is. To achieve higher utilization, catalyst layer components must be distributed by means of engineered design, which can prevent aggregation.

关键词: catalyst utilization     PEMFC     commercialization     Pt/C catalyst     conduction    

Dendritic BiVO4 decorated with MnOx co-catalyst as an efficient hierarchical catalyst for photocatalytic

Jin Yang, Xuelian Liu, Hongbin Cao, Yanchun Shi, Yongbing Xie, Jiadong Xiao

《化学科学与工程前沿(英文)》 2019年 第13卷 第1期   页码 185-191 doi: 10.1007/s11705-018-1713-z

摘要: An appropriate co-catalyst can significantly promote the photocatalytic efficacy, but this has been seldom studied in the visible-light photocatalysis combined with ozone, namely photocatalytic ozonation. In this work, a dendritic bismuth vanadium tetraoxide (BiVO ) material composited with highly dispersed MnO nanoparticles was synthesized, and its catalytic activity is 86.6% higher than bare BiVO in a visible light and ozone combined process. Catalytic ozonation experiments, ultra-violet-visible (UV-Vis) diffuse reflectance spectra and photoluminescence spectra jointly indicate that MnO plays a triple role in this process. MnO strengthens the light adsorption and promotes the charge separation on the composite material, and it also shows good activity in catalytic ozonation. The key reactive species in this process is ·OH, and various pathways for its generation in this process is proposed. This work provides a new direction of catalyst preparation and pushes forward the application of photocatalytic ozonation in water treatment.

关键词: manganese oxide     bismuth vanadium tetraoxide     photocatalytic ozonation     hydroxyl radical     co-catalyst    

Insight into the promotion mechanism of activated carbon on the monolithic honeycomb red mud catalyst

《环境科学与工程前沿(英文)》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1337-7

摘要:

• Activated carbon was proposed to be an efficient accelerant for molded red mud catalyst.

关键词: NOx     Selective catalytic reduction     Iron-based catalyst     Red mud     Monolithic catalyst     Activated carbon    

Direct synthesis of diphenyl carbonate over heterogeneous catalyst: effects of structure of substitutedperovskite carrier on the catalyst activities

WU Guangwen, JIN Fang, WU Yuxin, ZHANG Guangxu, LI Dinghuo, WANG Cunwen, MA Peisheng

《化学科学与工程前沿(英文)》 2007年 第1卷 第1期   页码 59-64 doi: 10.1007/s11705-007-0012-x

摘要: The perovskite-type compound LaMnO was substituted for the part of La in position A and for the part of Mn in position B by citrate method. The phases were detected by X-ray diffraction. Powder morphologies were scanned by scanning electron microscopy. The valence of atoms was determined by X-ray photoelectron spectroscopy. It was found that the perovskite can form crystal defect and increase the proportion of high valence B element by doping. Active component Pd was loaded on various perovskite supports for synthesis of diphenyl carbonate. The results showed that the activities of catalysts in which supports have crystal defect by substitution were higher. It can be concluded that perovskite with defect structure by doping could lead to the formation of oxygen vacancy where the lattice oxygen became exchangeable with the oxygen gas. Also, this improved the redox process of the carrier by transferring electrons and activities of catalysts.

关键词: photoelectron spectroscopy     diphenyl carbonate     proportion     diffraction     perovskite    

Pd nano-catalyst supported on biowaste-derived porous nanofibrous carbon microspheres for efficient catalysis

《化学科学与工程前沿(英文)》 2023年 第17卷 第9期   页码 1289-1300 doi: 10.1007/s11705-023-2299-7

摘要: Environmental pollution caused by the presence of aromatic aldehydes and dyes in wastewater is a serious global concern. An effective strategy for the removal of these pollutants is their catalytic conversion, possibly to valuable compounds. Therefore, the design of efficient, stable and long-lifetime catalysts is a worthwhile research goal. Herein, we used nanofibrous carbon microspheres (NCM) derived from the carbohydrate chitin present in seafood waste, and characterized by interconnected nanofibrous networks and N/O-containing groups, as carriers for the manufacture of a highly dispersed, efficient and stable Pd nano-catalyst (mean diameter ca. 2.52 nm). Importantly, the carbonised chitin’s graphitized structure, defect presence and large surface area could promote the transport of electrons between NCM and Pd, thereby endowing NCM supported Pd catalyst with high catalytic activity. The NCM supported Pd catalyst was employed in the degradation of some representative dyes and the chemoselective hydrogenation of aromatic aldehydes; this species exhibited excellent catalytic activity and stability, as well as applicability to a broad range of aromatic aldehydes, suggesting its potential use in green industrial catalysis.

关键词: biowaste chitin     nanofibrous     palladium     nano-catalyst     catalysis    

Advanced materials: adsorbent and catalyst for environmental application

Junhua LI, Shubo DENG

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 301-301 doi: 10.1007/s11783-013-0529-9

Ni-Co bimetallic catalyst for CH

Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 476-480 doi: 10.1007/s11705-010-0512-y

摘要: A co-precipitation method was employed to prepare Ni/Al O -ZrO , Co/Al O -ZrO and Ni-Co/Al O -ZrO catalysts. Their properties were characterized by N adsorption (BET), thermogravimetric analysis TGA , temperature-programmed reduction (TPR), temperature-programmed desorption (CO -TPD), and temperature-programmed surface reaction (CH -TPSR and CO -TPSR). Ni-Co/Al O -ZrO bimetallic catalyst has good performance in the reduction of active components Ni, Co and CO adsorption. Compared with mono-metallic catalyst, bimetallic catalyst could provide more active sites and CO adsorption sites (C+ CO = 2CO) for the methane-reforming reaction, and a more appropriate force formed between active components and composite support (SMSI) for the catalytic reaction. According to the CH -CO -TPSR, there were 80.9% and 81.5% higher CH and CO conversion over Ni-Co/Al O -ZrO catalyst, and its better resistance to carbon deposition, less than 0.5% of coke after 4 h reaction, was found by TGA. The high activity and excellent anti-coking of the Ni-Co/Al O -ZrO catalyst were closely related to the synergy between Ni and Co active metal, the strong metal-support interaction and the use of composite support.

关键词: Ni-Co bimetallic catalyst     composite support     CH4 reforming with CO2    

Sulfonic acid-functionalized mesoporous silica catalyst with different morphology for biodiesel production

《化学科学与工程前沿(英文)》 2022年 第16卷 第8期   页码 1198-1210 doi: 10.1007/s11705-021-2133-z

摘要: Sulfonic acid functionalized mesoporous silica based solid acid catalysts with different morphology were designed and fabricated. The synthesized materials were characterized by various physicochemical and spectroscopic techniques like scanning electron microscope-energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller surface area, thermogravimetric analysis and n-butylamine acidity. The shape of catalysts particles plays an important role in its activity. The sulfonic acid functionalized mesoporous silica catalysts of spherical shape and the cube shape were assessed for catalytic activity in biodiesel production. The catalytic biodiesel production reaction over the catalysts were studied by esterification of free fatty acid, oleic acid with methanol. The effect of various reaction parameters such as catalyst concentration, acid/alcohol molar ratio, catalyst amount, reaction temperature and reaction time on catalytic activity were investigated to optimize the conditions for maximum conversion. It was sulfonated cubic shape mesoporous silica which exhibited better activity as compared to the spherical shape silica catalysts. Additionally, the catalyst was regenerated and reused up to three cycles without any significant loss in activity. The present catalysts exhibit superior performance in biodiesel production and it can be used for the several biodiesel feedstock’s that are rich in free fatty acids.

关键词: solid acid catalyst     mesoporous silica     sulfonic acid     biodiesel     esterification     oleic acid    

Synthesis of methanol and ethanol over CuZnAl slurry catalyst prepared by complete liquid-phase technology

Wei HUANG, Linmei YU, Wenhui LI, Zhili MA

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 472-475 doi: 10.1007/s11705-010-0525-6

摘要: A new method, named the complete liquid-phase technology, has been applied to prepare catalysts for methanol synthesis. Its main innovative thought lies in preparing slurry catalysts directly from raw solution. Activity tests indicate that the CuZnAl slurry catalyst prepared by the new method can efficiently catalyze conversion of syngas to ethanol in a slurry reactor, while CO conversion reaches 35.9% and ethanol selectivity is more than 20%, with a total alcohol selectivity of more than 87%. No deactivation was found during the 192 h reaction .

关键词: methanol     slurry     ethanol     complete liquid-phase technology     CuZnAl catalyst    

标题 作者 时间 类型 操作

Synthesis of boron modified CoMo/Al

Hui Shang, Chong Guo, Pengfei Ye, Wenhui Zhang

期刊论文

Abatement of mixed volatile organic compounds in a catalytic hybrid surface/packed-bed discharge plasma

Lianjie Guo, Nan Jiang, Jie Li, Kefeng Shang, Na Lu, Yan Wu

期刊论文

Synthesis, characterization and hydrotreating performance of supported tungsten phosphide catalysts

SUN Guida, LI Cuiqing, ZHOU Zhijun, LI Fengyan

期刊论文

Modeling nanostructured catalyst layer in PEMFC and catalyst utilization

Jiejing ZHANG, Pengzhen CAO, Li XU, Yuxin WANG

期刊论文

Ni-Bi 助剂用于α-Fe2O3

党珂,王拓,李澄澄,张冀杰,刘珊珊,巩金龙

期刊论文

Oxidant or catalyst for oxidation?

Jianzhi Huang, Huichun Zhang

期刊论文

Monte Carlo simulation of the PEMFC catalyst layer

WANG Hongxing, CAO Pengzhen, WANG Yuxin

期刊论文

Dendritic BiVO4 decorated with MnOx co-catalyst as an efficient hierarchical catalyst for photocatalytic

Jin Yang, Xuelian Liu, Hongbin Cao, Yanchun Shi, Yongbing Xie, Jiadong Xiao

期刊论文

Insight into the promotion mechanism of activated carbon on the monolithic honeycomb red mud catalyst

期刊论文

Direct synthesis of diphenyl carbonate over heterogeneous catalyst: effects of structure of substitutedperovskite carrier on the catalyst activities

WU Guangwen, JIN Fang, WU Yuxin, ZHANG Guangxu, LI Dinghuo, WANG Cunwen, MA Peisheng

期刊论文

Pd nano-catalyst supported on biowaste-derived porous nanofibrous carbon microspheres for efficient catalysis

期刊论文

Advanced materials: adsorbent and catalyst for environmental application

Junhua LI, Shubo DENG

期刊论文

Ni-Co bimetallic catalyst for CH

Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI

期刊论文

Sulfonic acid-functionalized mesoporous silica catalyst with different morphology for biodiesel production

期刊论文

Synthesis of methanol and ethanol over CuZnAl slurry catalyst prepared by complete liquid-phase technology

Wei HUANG, Linmei YU, Wenhui LI, Zhili MA

期刊论文