Topic
MCM-41
About: MCM-41 is a research topic. Over the lifetime, 2355 publications have been published within this topic receiving 91416 citations.
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TL;DR: In this paper, the results of synthesis, characterization and application of three metalloporphyrin catalysts (FeTPPCl, MnTPPCl and CoTPP), anchored on MCM-41, in the reaction of cyclohexene oxidation with hydrogen peroxide were presented.
Abstract: Metalloporphyrin catalysts are able to carry out selective oxidation of organic substrates with several oxidizing agents. Recently, mesoporous materials have been studied as supports because they present high specific surface area, better dispersion and regeneration properties. This work presents the results of synthesis, characterization and application of three metalloporphyrin catalysts (FeTPPCl, MnTPPCl and CoTPP, where TPP = tetraphenylporphyrin) anchored on MCM-41, in the reaction of cyclohexene oxidation with hydrogen peroxide. A modified sol–gel preparation was chosen for the synthesis of the MCM-41 mesoporous material, as well as the anchoring was followed by Soxhlet extraction to ensure strong adsorption of the complex. The supported materials were much more stable than pure metalloporphyrins. The synthesized catalysts were characterized by UV–vis, FTIR, XRD, ICP-AES, 29 Si MAS-NMR and thermal analysis, before and after incorporation. Evidence of the metalloporphyrin immobilization was confirmed by elemental analysis and their activity in the oxidation reaction. FeTPPCl/MCM-41 showed higher conversion than CoTPP/MCM-41 and MnTPPCl/MCM-41. However, MnTPPCl/MCM-41 even in low concentration on the support showed a good conversion for the direct oxidation of cyclohexene with the highest turnover number (1.54 × 10 5 ). All catalysts showed similar selectivity that favors allylic oxidation products over epoxidation. No leaching of the metalloporphyrins was observed after the reaction.
73 citations
TL;DR: In this paper, vanadium-containing silica catalysts (2.6 wt% V) were used for the dehydrogenation of 2-propanol, and a relationship between the selectivity towards propene and the effective acidity was established.
Abstract: Three series of vanadium-containing silica catalysts (2–7.6 wt% V) have been prepared by varying the synthesis method. In all cases, conversion values in the oxidative dehydrogenation of propane increase with the temperature, vanadium loading and reducibility. For impregnated and anchored catalysts, a relationship between the selectivity towards propene and the effective acidity, as determined in the dehydration of 2-propanol, can be established.
73 citations
TL;DR: In this article, high surface area MCM-41 containing copper catalysts (with different loading from 5 to 20 wt%) were synthesized using one-pot procedure for steam reforming of methanol (SRM) studies.
73 citations
TL;DR: It was observed that SnO(2) with higher surface areas had much higher sensitivities to hydrogen at 573 K and was synthesized using a cationic surfactant as a synthetic template using N-cetyl-N, N,N,N-trimethylammonium bromide as a template.
73 citations
TL;DR: In this paper, a detailed study about the relationship existing between the Ti loading in the catalyst, the acid properties and the catalytic efficacy is presented in this contribution. But the authors did not consider the effect of the presence of tetrahedral Ti species in the framework, the Bronsted acid sites were also generated at high Ti loadings.
73 citations