Stability of Ni/SiO
Bettina Stolze,Juliane Titus,Stephan A. Schunk,Andrian Milanov,Ekkehard Schwab,Roger Gläser
《化学科学与工程前沿(英文)》
2016年
第10卷
第2期
页码 281-293
doi:
10.1007/s11705-016-1568-0
摘要:
Ni/SiO -ZrO catalysts with Ni loadings of 1 to 13 wt-% were prepared, characterized by elemental analysis, X-ray diffraction, N sorption, temperature programmed oxidation, temperature programmed reduction, and tested for their activity and stability in the dry reforming of methane with carbon dioxide at 850 °C, gas hourly space velocity of 6000 and 1800 h and atmospheric pressure. The SiO -ZrO support as obtained through a simple and efficient sol-gel synthesis is highly porous ( = 90 m ·g , = 4.4 nm) with a homogeneously distributed Si-content of 3 wt-%. No loss of Si or formation of monoclinic ZrO , even after steaming at 850 °C for 160 h, was detectable. The catalyst with 5 wt-% Ni loading in its fully reduced state is stable over 15?h on-stream in the dry reforming reaction. If the catalyst was not fully reduced, a reduction during the early stages of dry reforming is accompanied by the deposition of up to 44 mg·g carbon as shown by experiments in a magnetic suspension balance. Rapid coking occurs for increased residence times and times-on-stream starting at 50 h. The Ni loading of 5 wt-% on SiO -ZrO was shown to provide an optimal balance between activity and coking tendency.
关键词:
Ni/SiO2-ZrO2
synthesis gas
dry reforming
coking
steaming
Catalytic hydrolysis of gaseous HCN over Cu–Ni/γ-Al
Linxia Yan, Senlin Tian, Jian Zhou, Xin Yuan
《环境科学与工程前沿(英文)》
2016年
第10卷
第6期
doi:
10.1007/s11783-016-0872-8
摘要:
? The Cu–Ni/γ-Al O catalyst was prepared to study HCN hydrolysis ? On catalyst calcined at 400°C, the HCN removal efficiency reaches a maximum. ? HCN removal is the highest at 480 min at a H O/HCN volume ratio of 150 ? The presence of CO facilitates HCN hydrolysis and increases NH production. ? O increases the HCN removal and NO production but decreases NH production GRAPHIC ABSTRACT To decompose efficiently hydrogen cyanide (HCN) in exhaust gas, g-Al O -supported bimetallic-based Cu–Ni catalyst was prepared by incipient-wetness impregnation method. The effects of the calcination temperature, H O/HCN volume ratio, reaction temperature, and the presence of CO or O on the HCN removal efficiency on the Cu–Ni/g-Al O catalyst were investigated. To examine further the efficiency of HCN hydrolysis, degradation products were analyzed. The results indicate that the HCN removal efficiency increases and then decreases with increasing calcination temperature and H O/HCN volume ratio. On catalyst calcined at 400°C, the efficiency reaches a maximum close to 99% at 480 min at a H O/HCN volume ratio of 150. The HCN removal efficiency increases with increasing reaction temperature within the range of 100°C–500°C and reaches a maximum at 500°C. This trend may be attributed to the endothermicity of HCN hydrolysis; increasing the temperature favors HCN hydrolysis. However, the removal efficiencies increases very few at 500°C compared with that at 400°C. To conserve energy in industrial operations, 400°C is deemed as the optimal reaction temperature. The presence of CO facilitates HCN hydrolysis andincreases NH production. O substantially increases the HCN removal efficiency and NO production but decreases NH production.
关键词:
Hydrogen cyanide
Cu–Ni/g-Al2O3
Catalytic hydrolysis
Efficient degradation of orange II by ZnMn
Qingzhuo Ni, Hao Cheng, Jianfeng Ma, Yong Kong, Sridhar Komarneni
《化学科学与工程前沿(英文)》
2020年
第14卷
第6期
页码 956-966
doi:
10.1007/s11705-019-1907-z
摘要:
A ZnMn O catalyst has been synthesized via a sucrose-aided combustion method and characterized by various analytical techniques. It is composed of numerous nanoparticles (15–110 nm) assembled into a porous structure with a specific surface area (SSA) of 19.1 m ·g . Its catalytic activity has been investigated for the degradation of orange II dye using three different systems, i.e., the photocatalysis system with visible light, the chemocatalysis system with bisulfite, and the photo-chemical catalysis system with both visible light and bisulfite. The last system exhibits the maximum degradation efficiency of 90%, much higher than the photocatalysis system (15%) and the chemocatalysis system (67%). The recycling experiments indicate that the ZnMn O catalyst has high stability and reusability and is thus a green and eximious catalyst. Furthermore, the potential degradation mechanisms applicable to the three systems are discussed with relevant theoretical analysis and scavenging experiments for radicals. The active species such as Mn(III), O , h , e , SO and HO are proposed to be responsible for the excellent degradation results in the photo-chemical catalysis system with the ZnMn O catalyst.
关键词:
ZnMn2O4
photo-chemical catalysis
bisulfite
dye degradation
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
Laboratory study on high-temperature adsorption of HCl by dry-injection of Ca(OH)
Junjun TAN,Guohua YANG,Jingqiao MAO,Huichao DAI
《环境科学与工程前沿(英文)》
2014年
第8卷
第6期
页码 863-870
doi:
10.1007/s11783-013-0618-9
摘要:
Combustion-generated hydrogen chloride (HCl) is considered to be a very hazardous acid gaseous pollutant. This paper presents a laboratory study on the dry adsorption of HCl. The experiments were conducted in a dual-layer granular bed filter, at gas temperatures of 500°C–700°C and (Ca)/ (Cl)molar ratios of 1.0–5.0 using the silver nitrate titration method by dry adsorbent powders Ca(OH) . Mainly, the adsorption efficiency of HCl and utilization efficiency of Calcium were studied, by varying relevant factors including (Ca)/ (Cl), temperature, feeding method, water vapor and CO . With a relatively higher HCl concentration of 1000 ppm, the experimental results revealed that 600°C may be the optimum temperature for HCl adsorption when optimum (Ca)/ (Cl) was 2.5 in our tests. The results also demonstrated that the feeding at a constant pressure was more effective, and the HCl adsorption efficiency could rapidly reach over 90% with (Ca)/ (Cl) = 2.5 at 600°C. Furthermore, the HCl adsorption efficiency was found to be slightly promoted by water vapor, while could be impeded by CO , and the utilization efficiency of calcium could be up to 74.4% without CO , while was only 36.8% with CO when (Ca)/ (Cl) was 2.5 at 600°C.
关键词:
acid gas HCl
Ca(OH)2
dry adsorption
high temperature
dual-layer granular bed filter
Bamboo-like -doped carbon nanotubes encapsulating M(Co, Fe)-Ni alloy for electrochemical production of
《化学科学与工程前沿(英文)》
2022年
第16卷
第4期
页码 498-510
doi:
10.1007/s11705-021-2082-6
摘要:
The electrochemical conversion of CO2-H2O into CO-H2 using renewable energy is a promising technique for clean syngas production. Low-cost electrocatalysts to produce tunable syngas with a potential-independent CO/H2 ratio are highly desired. Herein, a series of N-doped carbon nanotubes encapsulating binary alloy nanoparticles (MxNi-NCNT, M= Fe, Co) were successfully fabricated through the co-pyrolysis of melamine and metal precursors. The MxNi-NCNT samples exhibited bamboo-like nanotubular structures with a large specific surface area and high degree of graphitization. Their electrocatalytic performance for syngas production can be tuned by changing the alloy compositions and modifying the electronic structure of the carbon nanotube through the encapsulated metal nanoparticles. Consequently, syngas with a wide range of CO/H2 ratios, from 0.5:1 to 3.4:1, can be produced on MxNi-NCNT. More importantly, stable CO/H2 ratios of 2:1 and 1.5:1, corresponding to the ratio to produce biofuels by syngas fermentation, could be realized on Co1Ni-NCNT and Co2Ni-NCNT, respectively, over a potential window of –0.8 to –1.2 V versus the reversible hydrogen electrode. Our work provides an approach to develop low-cost and potential-independent electrocatalysts to effectively produce syngas with an adjustable CO/H2 ratio from electrochemical CO2 reduction.
关键词:
electrochemical reduction of CO2
syngas
N-doped carbon nanotubes
encapsulated alloy nanoparticles
CO/H2 ratio
标题
作者
时间
类型
操作
CO<sub>2sub> methanation and co-methanation of CO and CO<sub>2sub> over Mn-promoted Ni/Al<sub>2sub>O<sub>3sub> catalysts
Kechao Zhao,Zhenhua Li,Li Bian
期刊论文
Formation of CaCO hollow microspheres in carbonated distiller waste from Solvay soda ash plants
期刊论文
Stability of Ni/SiO
Bettina Stolze,Juliane Titus,Stephan A. Schunk,Andrian Milanov,Ekkehard Schwab,Roger Gläser
期刊论文
An investigation of the CHOH and CO selectivity of CO hydrogenation over Cu–Ce–Zr catalysts
期刊论文
Catalytic hydrolysis of gaseous HCN over Cu–Ni/γ-Al
Linxia Yan, Senlin Tian, Jian Zhou, Xin Yuan
期刊论文
Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten MgCl<sub>2sub>–KCl–NaCl salt with over-added
期刊论文
铝电解用Fe-Ni-Co-Al<sub>2sub>O<sub>3sub>金属陶瓷惰性阳极
邱竹贤,石忠宁,徐君莉
期刊论文
Efficient degradation of orange II by ZnMn
Qingzhuo Ni, Hao Cheng, Jianfeng Ma, Yong Kong, Sridhar Komarneni
期刊论文
Ni-Co bimetallic catalyst for CH
Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI
期刊论文
Laboratory study on high-temperature adsorption of HCl by dry-injection of Ca(OH)
Junjun TAN,Guohua YANG,Jingqiao MAO,Huichao DAI
期刊论文
Bamboo-like -doped carbon nanotubes encapsulating M(Co, Fe)-Ni alloy for electrochemical production of
期刊论文
Generation of enhanced stability of SnO/In(OH)/InP for photocatalytic water splitting by SnO protection
期刊论文
Design and analysis of dual fuel methanol-power
poly-generation
Minghua WANG , Zheng LI , Weidou NI ,
期刊论文
以NH<sub>3sub>OH+/NH<sub>2sub>NH<sub>3sub>+作为B位阳离子的无金属六方钙钛矿含能材料
尚宇, 余志鸿, 黄瑞康, 陈劭力, 刘德轩, 陈晓娴, 张伟雄, 陈小明
期刊论文
Synergistic utilization of coal and other energy – Key to low carbon economy
Weidou NI, Zhen CHEN
期刊论文