Synthesis of framework lithium zirconium molybdate phosphates and their catalytic properties in ethanol conversion reactions

2015 ◽  
Vol 51 (7) ◽  
pp. 711-717 ◽  
Author(s):  
A. B. Il’in ◽  
M. M. Ermilova ◽  
N. V. Orekhova ◽  
A. B. Yaroslavtsev
Author(s):  
Pavel Mayorov ◽  
Elena Asabina ◽  
Anna Zhukova ◽  
Diana Osaulenko ◽  
Vladimir Pet’kov ◽  
...  

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Anchale Tresatayawed ◽  
Peangpit Glinrun ◽  
Bunjerd Jongsomjit

The present study aims to investigate the catalytic ethanol dehydration to higher value products including ethylene, diethyl ether (DEE), and acetaldehyde. The catalysts used for this reaction were WO3/TiO2catalysts having W loading of 13.5 wt.%. For a comparative study, the TiO2supports employed were varied by two different preparation methods including the sol-gel and solvothermal-derived TiO2supports, denoted as TiO2-SG and TiO2-SV, respectively. It is obvious that the different preparation methods essentially altered the physicochemical properties of TiO2supports. It was found that the TiO2-SV exhibited higher surface area and pore volume and larger amounts of acid sites than those of TiO2-SG. As a consequence, different characteristics of support apparently affected the catalytic properties of WO3/TiO2catalysts. As expected, both catalysts WO3/TiO2-SG and WO3/TiO2-SV exhibited increased ethanol conversion with increasing temperatures from 200 to 400°C. It appeared that the highest ethanol conversion (ca. 88%) at 400°C was achieved by the WO3/TiO2-SV catalysts due to its high acidity. It is worth noting that the presence of WO3onto TiO2-SV yielded a remarkable increase in DEE selectivity (ca. 68%) at 250°C. In summary, WO3/TiO2-SV catalyst is promising to convert ethanol into ethylene and DEE, having the highest ethylene yield of ca. 77% at 400°C and highest DEE yield of ca. 26% at 250°C. These can be attributed to proper pore structure, acidity, and distribution of WO3.


2016 ◽  
Vol 2 (1) ◽  
pp. 83-86
Author(s):  
Kuzmina Raisa Ivanovna ◽  
Pilipenko Anton Yurievich

AbstractIn this paper, we have shown modification of high-silicon zeolite ZSM-5 by zirconium, and the results of ethanol conversion on this catalyst. Effect of process parameters on the selectivity of ethanol dehydration products was analyzed. In addition, a mechanism of aromatic hydrocarbons formation including reactions of dehydrogenation, dehydrocyclization and alkylation of intermediates was discussed. It was found that with increasing temperature a selectivity decreased for reactions of isomerization and increased selectivity for aromatic products and products of cracking reactions. The data also confirms that hexene-1 is an intermediate in the conversion process of ethanol and the catalyst system with 1% Zr-ZSM-5 has a bi-functionality. Catalytic properties of the system in the conversion of hydrocarbons are determined by the presence on their surface of both Broensted and Lewis acid sites.


1995 ◽  
Vol 34 (3-4) ◽  
pp. 359-364 ◽  
Author(s):  
V. Gruver ◽  
A. Sun ◽  
J. J. Fripiat

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 659
Author(s):  
Asato Nakagiri ◽  
Kazuya Imamura ◽  
Kazumichi Yanagisawa ◽  
Ayumu Onda

Hydroxyapatite is known to have excellent catalytic properties for ethanol conversion and lactic acid conversion, and their properties are influenced by the elemental composition, such as Ca/P ratio and sodium content. However, few reports have been examined for the surface acid–base nature of hydroxyapatites containing sodium ions. We prepared nanocrystalline hydroxyapatite (Ca-HAP) catalysts with various Ca/P ratios and sodium contents by the hydrothermal method. The adsorption and desorption experiments using NH3 and CO2 molecules and the catalytic reactions for 2-propenol conversion revealed that the surface acid–base natures changed continuously with the bulk Ca/P ratios. Furthermore, the new catalytic properties of hydroxyapatite were exhibited for 1,6-hexanediol conversion. The non-stoichiometric Ca-HAP(1.54) catalyst with sodium ions of 2.3 wt% and a Ca/P molar ratio of 1.54 gave a high 5-hexen-1-ol yield of 68%. In contrast, the Ca-HAP(1.72) catalyst, with a Ca/P molar ratio of 1.72, gave a high cyclopentanemethanol yield of 42%. Both yields were the highest ever reported in the relevant literature. It was shown that hydroxyapatite also has excellent catalytic properties for alkanediol conversion because the surface acid–base properties can be continuously controlled by the elemental compositions, such as bulk Ca/P ratios and sodium contents.


2008 ◽  
Vol 81 (1) ◽  
pp. 17-22 ◽  
Author(s):  
M. V. Sukhanov ◽  
I. A. Shchelokov ◽  
M. M. Ermilova ◽  
N. V. Orekhova ◽  
V. I. Pet’kov ◽  
...  

2016 ◽  
Vol 269 ◽  
pp. 82-87 ◽  
Author(s):  
Karthikeyan K. Ramasamy ◽  
Michel Gray ◽  
Heather Job ◽  
Colin Smith ◽  
Yong Wang

Author(s):  
L.D. Schmidt ◽  
K. R. Krause ◽  
J. M. Schwartz ◽  
X. Chu

The evolution of microstructures of 10- to 100-Å diameter particles of Rh and Pt on SiO2 and Al2O3 following treatment in reducing, oxidizing, and reacting conditions have been characterized by TEM. We are able to transfer particles repeatedly between microscope and a reactor furnace so that the structural evolution of single particles can be examined following treatments in gases at atmospheric pressure. We are especially interested in the role of Ce additives on noble metals such as Pt and Rh. These systems are crucial in the automotive catalytic converter, and rare earths can significantly modify catalytic properties in many reactions. In particular, we are concerned with the oxidation state of Ce and its role in formation of mixed oxides with metals or with the support. For this we employ EELS in TEM, a technique uniquely suited to detect chemical shifts with ∼30Å resolution.


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