Effect of MgO Addition on the Properties of Ni/Al2O3 and Its Catalytic Activity in Hydrogenation of N-(2`,3`-dimethoxy benzyl)-3,4-dioxy-methylene-phenylethylamine

2019 ◽  
Vol 41 (5) ◽  
pp. 796-796
Author(s):  
Guosheng Wang Guosheng Wang ◽  
Xinxin Zhao and Siyu Han Xinxin Zhao and Siyu Han

the nickel based alumina-supported catalysts modified or promoted by magnesia were prepared by wet impregnation and successfully used for hydrogenation of N-(2`,3`-dimethoxy benzyl)-3,4-dioxy-methylene-phenylethylamine, the 20Ni-6MgO/74Al2O3 samples exhibits the highest BET surface area, the largest pore volume, and the largest pore diameter in all of the samples such as Ni/Al2O3 and 20Ni-xMgO(80-x)Al2O3 excepted the highest BET surface area of Ni/Al2O3. the average pore diameter of the 20Ni-6MgO/74Al2O3 samples were two times as large as Ni/Al2O3, it was indicated that the function of expanding role or the mesoporosity was increased by addition of MgO, and MgO might be regarded as pore-enlarge agent for the bare Al2O3 support and benefit for the transport of large molecules reactants and products The weak formation of MgO-Al2O3 and MgO-NiO solid solution as a result of competing interaction of MgO with Al2O3 support and NiO precursors restrained the strong interaction of NiO species with Al2O3 support, which favored the dispersion of active Ni centers and improved the reducible degree of NiO species on the surface of the catalysts. The improvement of basicity or the decrease in the number of acid centers in the catalysts avoid the secondary reactions, and subsequently resulted in high catalytic activity. The utilization of meso-porous 20Ni-6MgO/74Al2O3 for catalytic hydrogenation of N-(2`,3`-dimethoxy benzyl)-3,4-dioxy-methylene-phenylethylamine(Shiff’s base) with the highest selectivity of 99.70% and yields of 94.36% implied that the instead of Raney Ni was feasible.

2006 ◽  
Vol 951 ◽  
Author(s):  
Sorapong Pavasupree ◽  
Supachai Ngamsinlapasathian ◽  
Yoshikazu Suzuki ◽  
Susumu Yoshikawa

ABSTRACTNanorods/nanoparticles TiO2 with mesoporous structure were synthesized by hydrothermal method at 150 °C for 20 h. The samples characterized by XRD, SEM, TEM, SAED, HRTEM, and BET surface area. The nanorods had diameter about 10-20 nm and the lengths of 100-200 nm, the nanoparticles had diameter about 5-10 nm. The prepared material had average pore diameter about 7-12 nm. The BET surface area and pore volume of the sample are about 203 m2/g and 0.655 cm3/g, respectively. The nanorods/nanoparticles TiO2 with mesoporous structure showed higher photocatalytic activity (I3− concentration) than the nanorods TiO2, nanofibers TiO2, mesoporous TiO2, and commercial TiO2 (ST-01, P-25, JRC-01, and JRC-03). The solar energy conversion efficiency (η) of the cell using nanorods/nanoparticles TiO2 with mesoporous structure was about 7.12 % with Jsc of 13.97 mA/cm2, Voc of 0.73 V and ff of 0.70; while η of the cell using P-25 reached 5.82 % with Jsc of 12.74 mA/cm2, Voc of 0.704 V and ff of 0.649.


2015 ◽  
Vol 75 (11) ◽  
Author(s):  
Farid Nasir Ani ◽  
Muhammad Mat Junoh ◽  
Zarina Ab Muis

A study was conducted on Mukah coal using fixed bed reactor and one step activation with varying resident time and temperatures. CO2 gas was used for the activation process. The one-step continuous process comprised of carbonization and activation processes. The burn off analysis for 80 grams of Mukah coal was done to obtain volatiles removal at various carbonization temperatures. The results obtained showed that at 900oC, the percentages of burn off and the remaining weight were 42.2% and 57.8% respectively. Micrometrics ASAP2010 was used to analyze Mukah coal activated carbon in obtaining the BET surface area, the micropore area, and the average pore diameter. The results obtained indicated that activation at 900oC gave the highest BET surface area with 675m2/g, while the highest micropore area with 427 m2/g was obtained at 800oC. In addition, the average pore diameter range was within 18.5 to 26.4 A. 


2009 ◽  
Vol 79-82 ◽  
pp. 1907-1910
Author(s):  
Zhi Gang Xie

Porous activated carbon was prepared from orange wastes using zinc chloride as an activating agent by one-step carbonization method. Effects of impregnation ratio, carbonization temperature and heat preservation time on pore characteristics of activated carbon were studied. The porous structures of the orange wastes activated carbon were investigated by BET, D-R equations, BJH equations and Kelvin theory. The morphology was observed using transmission electron microscopy (TEM). The mesoporous activated carbon is gained when the impregnation ratio is 3:1; the carbonization temperature is 550°Cand heat preservation time is 1.0 h. The activated carbon has total pore volume 2.098 cm3/g, mesoporous pore volume 1.438 cm3/g, with a high BET surface area 1476m2/g. The pore distribution of the mesoporous activated carbon is very concentrative, with average pore diameter of 3.88nm. While, the high specific surface area activated carbon is gained when the impregnation ratio is 2:1; the carbonization temperature is 550°Cand heat preservation time is 1.0 h. The activated carbon has high BET surface area 1909 m2/g, while the total pore volume is only 1.448cm3/g and microporous pore volume is 0.889cm3/g, with average pore diameter of 2.29 nm.


2003 ◽  
Vol 47 (1) ◽  
pp. 83-87
Author(s):  
C. Hung-Lung ◽  
T.-C. Chen ◽  
M.-C. Tsai ◽  
Y.-L. Chen

This study selected biosolids from a petrochemical wastewater treatment plant as the raw material. The sludge was immersed in 0 to 5 mol l-1 of ZnCl2 solutions and pyrolyzed at different temperatures. When the sludge was pyrolyzed for 30 min at temperatures of 400, 500, 600, and 700°C, the corresponding surface area of the biosolid adsorbent was 46, 401, 921, and 727 m2/g, respectively. Pore size analysis indicated that the mesopore (20 to 500 Å) contributed more than the macropore and micropore in the sludge pyrolytic residue. When the benzene influent concentration was 800 ppmv, the adsorption capacity ranged from 59 to 164 mg/g for different biosolid adsorbents. A larger BET surface area and smaller average pore diameter yielded a larger benzene adsorption capacity.


2006 ◽  
Vol 951 ◽  
Author(s):  
Sorapong Pavasupree ◽  
Supachai Ngamsinlapasathian ◽  
Yoshikazu Suzuki ◽  
Susumu Yoshikawa

ABSTRACTHigh surface area nanosheet TiO2 with mesoporous structure were synthesized by hydrothermal method at 130 °C for 12 h. The samples characterized by XRD, SEM, TEM, SAED, and BET surface area. The nanosheet structure was slightly curved and approximately 50-100 nm in width and several nanometers in thickness. The as-synthesized nanosheet TiO2 had average pore diameter about 3-4 nm. The BET surface area and pore volume of the sample were about 642 m2/g and 0.774 cm3/g, respectively. The solar energy conversion efficiency (η) of the cell using nanorods/nanoparticles TiO2 (from the nanosheet calcined at 450 °C for 2 h) with mesoporous structure was about 7.08 % with Jsc of 16.35 mA/cm2, Voc of 0.703 V and ff of 0.627; while η of the cell using P-25 reached 5.82 % with Jsc of 12.74 mA/cm2, Voc of 0.704V and ff of 0.649.


2017 ◽  
Vol 68 (3) ◽  
pp. 483-486
Author(s):  
Constantin Sorin Ion ◽  
Mihaela Bombos ◽  
Gabriel Vasilievici ◽  
Dorin Bombos

Desulfurisation of atmospheric distillation gasoline and gas oil was performed by adsorption process on Fe/ bentonite. The adsorbent was characterized by determining the adsorption isotherms, specific surface area, pore volume and average pore diameter. Adsorption experiments of atmospheric distillation gasoline and gas oil were performed in continuous system at 280�320oC, 5 atm and volume hourly space velocities of 1�2 h-1. The efficiency of adsorption on Fe / bentonite was better at desulphurisation of gasoline versus gas oil.


2021 ◽  
Vol 1036 ◽  
pp. 130-136
Author(s):  
Ting Qun Tan ◽  
Lei Geng ◽  
Yan Lin ◽  
Yan He

In order to prepare carbon nanotubes with high specific surface area, small diameter, low resistivity, high purity and high catalytic activity, the Fe-Mo/Al2O3 catalyst was prepared based on the microreactor. The influence of different Fe/Al molar ratios on the catalyst and the carbon nanotubes prepared was studied through BET, SEM, TEM and other detection methods. Studies have shown that the pore structure of the catalyst is dominated by slit pores at a lower Fe/Al molar ratio. The catalytic activity is the highest when the Fe/Al molar ratio is 1:1, reaching 74.1%. When the Fe/Al molar ratio is 1:2, the catalyst has a higher specific surface area, the maximum pore size is 8.63 nm, and the four-probe resistivity and ash content of the corresponding carbon nanotubes are the lowest. The higher the proportion of aluminum, the higher the specific surface area of the catalyst and the carbon nanotubes, and the finer the diameter of the carbon nanotubes, which gradually tends to relax. The results show that when the Fe/Al molar ratio is 1:2, although the catalytic activity of the catalyst is not the highest, the carbon nanotubes prepared have the best performance.


2014 ◽  
Vol 69 (5) ◽  
Author(s):  
Mukhamad Nurhadi ◽  
Jon Efendi ◽  
Lee Siew Ling ◽  
Teuku Meurah Indra Mahlia ◽  
Ho Chin Siong ◽  
...  

Titanium dioxide supported sulfonated low rank coal catalyst possesses high catalytic activity in liquid phase oxidation of styrene with aqueous hydrogen peroxide at room temperature. The catalysts were prepared by sulfonation with concentrated sulfuric acid and impregnation of titanium dioxide (500-2500 µmol). The effect of titanium dioxide impregnation and calcinations on the catalysts were studied by X-ray diffraction, UV-vis diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, BET surface area, field emission scanning electron microscopy and hydrophobicity measurement. The catalytic activity of the catalysts in the oxidation of styrene by aqueous H2O2 without calcination increased when the amount of titanium dioxide increased. Meanwhile, the catalytic activity of the catalyst calcined at 500oC for 2 h was lower than before calcination. It is suggested that the agglomeration of titanium dioxide and hydrophobicity play important role in the catalytic activity of titanium dioxide-supported sulfonated low rank coal in the oxidation of styrene with aqueous H2O2. 


Author(s):  
Istadi Istadi ◽  
Udin Mabruro ◽  
Bintang Ayu Kalimantini ◽  
Luqman Buchori ◽  
Didi Dwi Anggoro

<p>This paper was purposed for testing reusability and stability of calcium oxide-based catalyst (K<sub>2</sub>O/CaO-ZnO) over transesterification reaction of soybean oil with methanol to produce biodiesel. The K<sub>2</sub>O/CaO-ZnO catalyst was synthesized by co-precipitation method of calcium and zinc nitrates followed by impregnation of potassium nitrate. The fresh and used catalysts were tested after regeneration. The catalysts were characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and BET Surface Area in order to compare the catalyst structure between the fresh and used catalysts. The catalyst testing in transesterification proses was carried out at following operating conditions, i.e. catalyst weight of 6 wt.%, oil to methanol mole ratio of 1:15, and temperature of 60 oC. In addition, metal oxide leaching of K<sub>2</sub>O/CaO-ZnO catalyst during reaction was also tested. From the results, the catalysts exhibited high catalytic activity (80% fatty acid methyl ester (FAME) yield after three-cycles of usage) and acceptable reusability after regeneration. The catalyst also showed acceptable stability of catalytic activity, even after three-cycles of usage. Copyright © 2016 BCREC GROUP. All rights reserved</p><p><em>Received: 10<sup>th</sup> November 2015; Revised: 16<sup>th</sup> January 2016; Accepted: 16<sup>th</sup> January 2016</em></p><p><strong>How to Cite</strong>: Istadi, I., Mabruro, U., Kalimantini, B.A.,  Buchori, L., Anggoro, D.D. (2016). Reusability and Stability Tests of Calcium Oxide Based Catalyst (K<sub>2</sub>O/CaO-ZnO) for Transesterification of Soybean Oil to Biodiesel. <em>Bulletin of Chemical Reaction Engineering &amp; Catalysis</em>, 11 (1): 34-39. (doi:10.9767/bcrec.11.1.413.34-39)</p><p><strong>Permalink/DOI</strong>: <a href="http://dx.doi.org/10.9767/bcrec.11.1.413.34-39">http://dx.doi.org/10.9767/bcrec.11.1.413.34-39</a></p><p> </p>


1997 ◽  
Vol 15 (6) ◽  
pp. 465-476 ◽  
Author(s):  
G.A. El-Shobaky ◽  
A.M. Ghozza ◽  
G.M. Mohamed

Two samples of Cr2O3/Al2O3 were prepared by mixing a known mass of finely powdered Al(OH)3 with a calculated amount of CrO3 solid followed by drying at 120°C and calcination at 400°C. The amounts of chromium oxide employed were 5.66 and 20 mol% Cr2O3, respectively. The calcined solid specimens were then treated with different doses of γ-rays (20–160 Mrad). The surface and catalytic properties of the different irradiated solids were investigated using nitrogen adsorption at −196°C and the catalysis of CO oxidation by O2 at 300–400°C. The results revealed that γ-rays brought about a slight decrease in the BET surface area, SBET (15%), and in the total pore volume, Vp (20%), of the adsorbent containing 5.66 mol% Cr2O3. The same treatment increased the total pore volume, Vp (36%), and the mean pore radius, r̄ (43%), of the other adsorbent sample without changing its BET surface area. The catalytic activities of both catalyst samples were found to increase as a function of dose, reaching a maximum value at 80–160 Mrad and 40 Mrad for the solids containing 5.66 and 20 mol% Cr2O3, respectively. The maximum increase in the catalytic activity measured at 300°C was 59% and 100% for the first and second catalyst samples, respectively. The induced effect of γ-irradiation on the catalytic activity was an increase in the concentration of catalytically active sites taking part in chemisorption and in the catalysis of CO oxidation by O2 without changing their energetic nature. This was achieved by a progressive removal of surface hydroxy groups during the irradiation process.


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