Highly selective hydrogenation of CO2 to methanol over CuO–ZnO–ZrO2 catalysts prepared by a surfactant-assisted co-precipitation method

2015 ◽  
Vol 279 ◽  
pp. 394-404 ◽  
Author(s):  
Li Li ◽  
Dongsen Mao ◽  
Jun Yu ◽  
Xiaoming Guo
Keyword(s):  
Selective Hydrogenation ◽  
Precipitation Method ◽  
Hydrogenation Of Co2 ◽  
Co Precipitation ◽  
Surfactant Assisted

scholarly journals Effect of La2O3 as a Promoter on the Pt,Pd,Ni/MgO Catalyst in Dry Reforming of Methane Reaction

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 750 ◽  
Author(s):  
Ali M. A. Al-Najar ◽  
Faris A. J. Al-Doghachi ◽  
Ali A. A. Al-Riyahee ◽  
Yun Hin Taufiq-Yap
Keyword(s):  
Carbon Deposition ◽  
Dry Reforming ◽  
Dry Reforming Of Methane ◽  
Precipitation Method ◽  
Gravimetric Analysis ◽  
Bet Method ◽  
Spent Catalysts ◽  
Ft Ir ◽  
Co Precipitation ◽  
Surfactant Assisted

Pt,Pd,Ni/MgO, Pt,Pd,Ni/Mg0.97La3+0.03O, Pt,Pd,Ni/Mg0.93La3+0.07O, and Pt,Pd,Ni/Mg0.85La3+0.15O (1% of each of the Ni, Pd, and Pt) catalysts were prepared by a surfactant-assisted co-precipitation method. Samples were characterized by the XRD, XPS, XRF, FT-IR, H2-TPR, TEM, the Brunauer–Emmett–Teller (BET) method, and TGA and were tested for the dry reforming of methane (DRM). TEM and thermal gravimetric analysis (TGA) methods were used to analyze the carbon deposition on spent catalysts after 200 h at 900 °C. At a temperature of 900 °C and a 1:1 CH4:CO2 ratio, the tri-metallic Pt,Pd,Ni/Mg0.85La3+0.15O catalyst with a lanthanum promoter showed a higher conversion of CH4 (85.01%) and CO2 (98.97%) compared to the Ni,Pd,Pt/MgO catalysts in the whole temperature range. The selectivity of H2/CO decreased in the following order: Pt,Pd,Ni/Mg0.85La3+0.15O > Pt,Pd,Ni/Mg0.93La3+0.07O > Pt,Pd,Ni/Mg0.97La3+0.03O > Ni,Pd,Pt/MgO. The results indicated that among the catalysts, the Pt,Pd,Ni/Mg0.85La23+0.15O catalyst exhibited the highest activity, making it the most suitable for the dry reforming of methane reaction.

Synthesis and magnetic properties of (Eu–Ni) substituted Y-type hexaferrite by surfactant assisted co-precipitation method

2015 ◽  
Vol 385 ◽  
pp. 386-393 ◽  
Author(s):  
Irshad Ali ◽  
M.U. Islam ◽  
Imran sadiq ◽  
Nazia Karamat ◽  
Aisha Iftikhar ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Precipitation Method ◽  
Co Precipitation ◽  
Surfactant Assisted

scholarly journals Selective Hydrogenation of Benzene to Cyclohexene over Ru-Zn Catalysts: Investigations on the Effect of Zn Content and ZrO2 as the Support and Dispersant

Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 513 ◽  
Author(s):  
Haijie Sun ◽  
Zhihao Chen ◽  
Lingxia Chen ◽  
Huiji Li ◽  
Zhikun Peng ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Selective Hydrogenation ◽  
Photoelectron Spectroscopy ◽  
Supported Catalyst ◽  
Precipitation Method ◽  
Molar Ratio ◽  
Impregnation Method ◽  
X Ray ◽  
Zn Content ◽  
Co Precipitation

m-ZrO2 (monoclinic phase) supported Ru-Zn catalysts and unsupported Ru-Zn catalysts were synthesized via the impregnation method and co-precipitation method, respectively. The catalytic activity and selectivity were evaluated for selective hydrogenation of benzene towards cyclohexene formation. Catalyst samples before and after catalytic experiments were thoroughly characterized via X-ray diffraction (XRD), X-ray Fluorescence (XRF), transmission electron microscopy (TEM), N2-sorption, X-ray photoelectron spectroscopy (XPS), H2-temperature programmed reduction (H2-TPR), and a contact angle meter. It was found that Zn mainly existed as ZnO, and its content was increased in Ru-Zn/m-ZrO2 by enhancing the Zn content during the preparation procedure. This results in the amount of formed (Zn(OH)2)3(ZnSO4)(H2O)3 increasing and the catalyst becoming more hydrophilic. Therefore, Ru-Zn/m-ZrO2 with adsorbed benzene would easily move from the oil phase into the aqueous phase, in which the synthesis of cyclohexene took place. The generated cyclohexene then went back into the oil phase, and the further hydrogenation of cyclohexene would be retarded because of the high hydrophilicity of Ru-Zn/m-ZrO2. Hence, the selectivity towards cyclohexene formation over Ru-Zn/m-ZrO2 improved by increasing the Zn content. When the theoretical molar ratio of Zn to Ru was 0.60, the highest cyclohexene yield of 60.9% was obtained over Ru-Zn (0.60)/m-ZrO2. On the other hand, when m-ZrO2 was utilized as the dispersant (i.e., employed as an additive during the reaction), the catalytic activity and selectivity towards cyclohexene synthesis over the unsupported Ru-Zn catalyst was lower than that achieved over the Ru-Zn catalyst with m-ZrO2 as the support. This is mainly because the supported catalyst sample demonstrated superior dispersion of Ru, higher content of (Zn(OH)2)3(ZnSO4)(H2O)3, and a stronger electronic effect between Ru and ZrO2. The Ru-Zn(0.60)/m-ZrO2 was reused 17 times without any regeneration, and no loss of catalytic activity and selectivity towards cyclohexene formation was observed.

Preparation of High Surface Area Ni-SDC Cermets Using a Surfactant-Assisted Co-Precipitation Method

2006 ◽  
Vol 942 ◽  
Author(s):  
Sang Joon Park ◽  
Tae Wook Eom ◽  
Jae Eun Oh ◽  
Hae Kwang Yang ◽  
Kyung Hwan Kim
Keyword(s):  
Surface Area ◽  
Cetyltrimethylammonium Bromide ◽  
High Surface ◽  
High Surface Area ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Two Phases ◽  
Co Precipitation ◽  
Surfactant Assisted

ABSTRACTA surfactant-assisted co-precipitation method was employed for obtaining high surface area Ni-SDC with improved structural properties for SOFC applications. In the work, a cationic surfactant, cetyltrimethylammonium bromide(CTAB) was employed with NiCl2, SmCl3 and CeCl3 as precursors and NH4OH as mineralizer. The elimination of surfactants upon calcination gives rise to the formation of high surface area NiO-SDC. When calcined at 600°C, the powders with surface area of 249 m2/g, were obtained and the pore size was 14.45 nm. The powders consist of two phases, the cubic NiO and SDC confirmed with X-ray diffraction identification.

Surfactant assisted synthesis of SrFe10Al2O19: Magnetic and Supercapacitor ferrite

MRS Advances ◽  
2016 ◽  
Vol 1 (45) ◽  
pp. 3099-3106 ◽  
Author(s):  
D. Neupane ◽  
H. Adhikari ◽  
B. Sapkota ◽  
J. Candler ◽  
R. Gupta ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Precipitation Method ◽  
Ammonium Bromide ◽  
Concomitant Increase ◽  
Cetyltrimethyl Ammonium Bromide ◽  
Structure Morphology ◽  
Powder Particles ◽  
Cetyltrimethyl Ammonium ◽  
Co Precipitation ◽  
Surfactant Assisted

ABSTRACTThe aluminum doped SrFe12O19 hexaferrite samples were prepared via co-precipitation method using cetyltrimethyl ammonium bromide (CTAB) as a surfactant. The effects of CTAB content (x = 0, 1, 3, 6 and 9 wt. %) on the structure, morphology, and electrocapacitive behavior of the SrFe10Al2O19 nanoparticles were investigated. The use of CTAB was observed to be effective in eliminating α-Fe2O3 phase from samples. Morphological changes including grain and crystallite size was noticed with the increase in the CTAB content. With the increase in CTAB, powder particles grew in size and thickness. A concomitant increase in magnetization due to crystal growth was observed. Electrochemical performance of supercapacitors was evaluated by cyclic voltammetry (CV). Highest power density of 368.09 WKg-1 and energy density of 0.916 WhKg-1 was observed for 3% and 1% CTAB samples, respectively.

Sign in / Sign up

Export Citation Format

Share Document