Decomposition of Energetic Ionic Liquid Over IrCu/Honeycomb Catalysts

2020 ◽  
Vol 20 (11) ◽  
pp. 7065-7069
Author(s):  
Jaegyu Woo ◽  
Dalsan Yoo ◽  
Seolyeong Oh ◽  
Jong-Ki Jeon

The objective of this study is to elucidate the influence of a loading procedure of iridium and copper oxides over cordierite honeycomb support on catalytic performance during the decomposition of a hydroxylammonium nitrate (HAN) solution. Iridium and copper composite oxides were successfully supported on the cordierite honeycomb at the same time by repeating the wash coating process more than 2 times. Through the wash coating process, Cu and Ir were supported up to 43.4% and 4.9%, respectively. The cordierite honeycomb without active metal plays little role as a catalyst to lower the decomposition temperature. It was found that IrCu/honeycomb-2 catalyst, which was prepared by repeating the wash coating procedure twice, is an optimal catalyst for the decomposition of HAN solution. The IrCu/honeycomb-2 catalyst had the effect of lowering the decomposition onset temperature by 27.1°C compared to thermal decomposition.

2015 ◽  
Vol 22 (03) ◽  
pp. 1550035 ◽  
Author(s):  
WEI-YUAN YU ◽  
SEN-HUI LIU ◽  
XIN-YA LIU ◽  
JIA-LIN SHAO ◽  
MIN-PEN LIU

In this study, Sn - Ag - Ti ternary alloy has been used as the active solder to braze pure aluminum and graphite in atmospheric conditions using ultrasonic vibration as an aid. The authors studied the formation, composition and decomposition temperature of the surface oxides of the active solder under atmospheric conditions. In addition, the wettability of Sn -5 Ag -8 Ti active solder on the surface of pure aluminum and graphite has also been studied. The results showed that the major components presented in the surface oxides formed on the Sn -5 Ag -8 Ti active solder under ambient conditions are TiO , TiO 2, Ti 2 O 3, Ti 3 O 5 and SnO 2. Apart from AgO and Ag 2 O 2, which can be decomposed at the brazing temperature (773 K), other oxides will not be decomposed. The oxide layer comprises composite oxides and it forms a compact layer with a certain thickness to enclose the melted solder, which will prevent the liquid solder from wetting the base metals at the brazing temperature. After ultrasonic vibration, the oxide layer was destroyed and the liquid solder was able to wet and spread out around the base materials. Furthermore, better wettability of the active solder was observed on the surface of graphite and pure aluminum at the brazing temperature of 773–823 K using ultrasonic waves. The ultrasonic wave acts as the dominant driving factor which promotes the wetting and spreading of the liquid solder on the surface of graphite and aluminum to achieve a stable and reliable brazed joint.


2012 ◽  
Vol 535-537 ◽  
pp. 31-35
Author(s):  
Tao Liu ◽  
Rong Bin Du ◽  
Xue Jun Kong

Composite oxides materials CuSnO3as anode materials for lithium-ion batteries were synthesized by chemical coprecipitation method using SnCl4•5H2O, NH3•H2O and Cu(NO3)2•3H2O as raw materials.The precursor CuSn(OH)6and CuSnO3powders were characterized by thermogravimertric(TG) analysis and differential thermal analysis(DTA), X-ray diffraction(XRD), and transmission electron microscope (TEM). The electrochemical properties of CuSnO3powders as anode materials of lithium ion batteries were investigated comparatively by galvanostatic charge-discharge experiments. The results show the average particle size of amorphous CuSnO3is 70nm. The initial capacity during the first lithium insertion is 1078 mA•h/g and the reversible charge capacity in first cycle is 775 mA•h/g. After 20 cycles, the charge capacity is 640 mA•h/g and this material shows moderate capacity fading with cycling. As a novel anode material for lithium ion batteries, amorphous CuSnO3demonstrates a large capacity and a low insertion potential with respect to Li metal.


RSC Advances ◽  
2017 ◽  
Vol 7 (45) ◽  
pp. 27863-27871 ◽  
Author(s):  
C. Doroftei ◽  
L. Leontie

Five nanosized perovskite and four ferrospinel powders were prepared by sol–gel self-combustion technique. The La0.6Pb0.2Mg0.2MnO3 perovskite was found to exhibit the best catalytic performance with respect to propane combustion at low temperatures.


2021 ◽  
Vol 21 (8) ◽  
pp. 4532-4536
Author(s):  
Munjeong Kim ◽  
Juyoung Kim ◽  
Young Min Jo ◽  
Jong-Ki Jeon

We investigated the influence of a copper loading strategy over a honeycomb structure on the catalytic performance during the decomposition of a hydroxylammonium nitrate (HAN) aqueous solution. Copper was supported on the honeycomb surface by means of a metal coating method (MC), i.e., a method of directly coating a metal, and a metal alumina coating method (MAC), i.e., a method of coating a mixture of metal and alumina. The properties of the catalysts were analyzed by N2 adsorption, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The Cu(16.8)/honeycomb-MC catalyst showed a lower decomposition onset temperature during the decomposition of the HAN aqueous solution compared to that over the Cu(7.0)/honeycomb- MAC catalyst, an outcome ascribed to the higher copper loading and the higher dispersion of copper in the Cu(16.8)/honeycomb-MC catalyst compared to that in the other catalyst. The Cu(16.8)/honeycomb-MC catalyst was confirmed to have both excellent activity and heat resistance during the decomposition of a HAN aqueous solution.


2011 ◽  
Vol 236-238 ◽  
pp. 724-727
Author(s):  
Feng Li ◽  
Hua Song ◽  
Hua Yang Zhang

A series of Al2O3-ZrO2 (AZ-X) composite oxides with different ZrO2 contents were prepared by a chemical precipitation method. Ni-P/AZ-X catalysts were prepared by temperature-programmed reduction. The supports and catalysts were extensively characterized by X-ray diffraction (XRD) and BET. The effects of support composition and P/Ni molar ratios on the catalytic performance of the catalysts were investigated by thiophene hydrodesulfurization (HDS) and pyridine hydrodenitrogenation (HDN). In comparison with Al2O3, Al2O3-ZrO2 (20 wt% ZrO2) composite oxide supported Ni-P catalyst exhibited higher activity and the activities of HDS and HDN increased by 7.5 % and 11.1 %, respectively. Studies of Ni-P/AZ-X catalysts with varying initial P/Ni molar ratios indicated that oxidic precursors with molar ratios of P/Ni = 2/1 yielded catalyst containing phase-pure Ni2P which exhibited optimal activity.


Catalysts ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 254 ◽  
Author(s):  
Kin Hong Liew ◽  
Tian Khoon Lee ◽  
Mohd Ambar Yarmo ◽  
Kee Shyuan Loh ◽  
Andreia F. Peixoto ◽  
...  

Herein, we report a facile procedure to synthesize the hybrid magnetic catalyst (Ru@CS-CR@Mn) using ruthenium (Ru) supported on ionically cross-linked chitosan-carrageenan (CS-CR) and manganese ferrite (MnFe2O4) nanoparticles with excellent catalytic activity. The ionic gelation of CS-CR is acting as a protecting layer to promote the encapsulation of MnFe2O4 and Ru nanoparticles by electrostatic interactions. The presence of an active metal and a CS-CR layer on the as-prepared Ru@CS-CR@Mn catalyst was well determined by a series of physicochemical analyses. Subsequently, the catalytic performances of the Ru@CS-CR@Mn catalysts were further examined in the 4-nitrophenol (4-NP) reduction reaction in the presence of sodium borohydride (reducing agent) at ambient temperature. The Ru@CS-CR@Mn catalyst performed excellent catalytic activity in the 4-NP reduction, with a turnover frequency (TOF) values of 925 h−1 and rate constant (k) of 0.078 s−1. It is worth to mentioning that the Ru@CS-CR@Mn catalyst can be recycled and reused up to at least ten consecutive cycles in the 4-NP reduction with consistency in catalytic performance. The Ru@CS-CR@Mn catalyst is particularly attractive as a catalyst due to its superior catalytic activity and superparamagnetic properties for easy separation. We foresee this catalyst having high potential to be extended in a wide range of chemistry applications.


2002 ◽  
Vol 17 (4) ◽  
pp. 821-830 ◽  
Author(s):  
L. P. Dorfman ◽  
D. L. Houck ◽  
M. J. Scheithauer ◽  
T. A. Frisk

Cupric tungstate (CuWO4) can be synthesized at high rates of conversion from a variety of solid reactants. However, the fixed copper content in the metal phase of CuWO4 limits its use as an oxide precursor for making W–Cu composite powders. This paper presents test results on synthesis of CuWO4-based composite oxides with a variable content of copper in the metal phase (5–25.7%). Hydrogen reduction converts the oxides to W–Cu composite powders with a unique phase distribution: each individual particle consists of a tungsten phase and a copper phase in which the tungsten phase substantially encapsulates the copper phase. These powders, when pressed and sintered without activators, yield high-density parts with a very fine microstructure and high electrical and thermal conductivity.


RSC Advances ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 2848-2853
Author(s):  
Xiaoliang Ren ◽  
Shufang Wang ◽  
Xiaoshu Ding ◽  
Dongsheng Zhang ◽  
Yanji Wang

A novel, active metal sintered membrane reactor anchored with Pt atoms was successfully developed. The membrane reactor exhibited excellent catalytic performance and stability towards continuous liquid-phase hydrogenation of nitroaromatic compounds.


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