The Nb-EISA catalyst with relatively low Nb loadings (∼2 wt %) shows exceptional propylene epoxidation performance with H2O2 as oxidant at 30-40 °C, 5-9 bar propylene pressure with nearly total pro...
Abstract:
The Nb-EISA catalyst with relatively low Nb loadings (∼2 wt %) shows exceptional propylene epoxidation performance with H2O2 as oxidant at 30–40 °C, 5–9 bar propylene pressure with nearly total pro...
TL;DR: In this paper, carbon overcoats are synthesized at mild temperatures, resulting in an open structure, as revealed by 13C NMR, which helps explain why the over-coats do not significantly block the active sites.
TL;DR: In this paper, easily available organic salts can stabilize/modify niobium (Nb) oxo-clusters and showed the highest catalytic activity, which can be attributed to the following reasons on the basis of characterization.
TL;DR: The direct epoxidation of propylene to propylene oxide (PO) using molecular oxygen is difficult to achieve as mentioned in this paper, but it has been achieved using metalloporphyrin catal...
TL;DR: The introduction of oxygen vacancies improved 1-hexene epoxidation performance over WO3−x/SBA-15 catalysts, which was attributed to the enhanced Lewis acidity of the active centers and the reduced energy barrier of the rate-determining step as mentioned in this paper .
TL;DR: In this paper , a safe one-pot catalytic process for directly producing tertiary butyl alcohol (TBA) from liquid-phase isobutane oxidation with oxygen is demonstrated.
TL;DR: In this paper, the liquid-phase epoxidation of propylene to propylene oxide (PO) over formed titanosilicate catalysts was investigated in a fixed-bed reactor.
TL;DR: In this article, the mesoporous niobium-silicates Nb-MMM-E have been characterized by elemental analysis, XRD, low-temperature N2 adsorption, SEM, XPS, DRS UVvis, and Raman techniques.
TL;DR: In this article, the catalytic performance of Niobium oxide-based materials, containing the same amount of Nb 2 O 5 (∼15 ¼wt%) and prepared by different methods, with that of pure Nb O 5 in the epoxidation of methyl oleate with hydrogen peroxide was compared.
TL;DR: In this paper, a biphasic process for the synthesis of propylene oxide (PO) from propylene is presented, using the long known catalyst, methyl trioxorhenium and aqueous hydrogen peroxide as the oxidant.
TL;DR: Niobium in varying amounts was successfully incorporated into SBA-16 material via a one-pot direct synthesis technique as discussed by the authors, which showed good cyclohexene epoxidation activity with H2O2 as oxidant, with the epoxide selectivity decreasing at higher Nb loadings.
Q1. What have the authors contributed in "110th anniversary: near-total epoxidation selectivity and hydrogen peroxide utilization with nb-eisa catalysts for propylene epoxidation" ?
The Nb-EISA catalyst with relatively low Nb loadings ( ∼2 wt % ) shows exceptional propylene epoxidation performance with H2O2 as oxidant at 30−40 °C, 5−9 bar propylene pressure with nearly total propylene oxide ( PO ) selectivity ( > 99 % ), H 2O2 utilization ( > 99 % ) toward PO formation, high productivity ( ∼3200 mg/h/g ), and mild Nb leaching ( 3−6 % ) this paper.
Q2. What future works have the authors mentioned in the paper "110th anniversary: near-total epoxidation selectivity and hydrogen peroxide utilization with nb-eisa catalysts for propylene epoxidation" ?
This provides guidance for future work in developing new catalyst synthesis methods to achieve optimum hydrophobicity that minimizes catalyst leaching to practically viable levels. Density functional theory calculations were used to investigate catalytic pathways38 and probable reasons21 for hydrogen peroxide decomposition and potential metal leaching. If methanol is used as solvent, the propylene oxide can further undergo hydrolysis and solvolysis reactions to form the corresponding byproducts, propylene glycol and isomers of methoxy propanol, respectively. It is noteworthy that the reaction of the niobium silicate structure with H2O2 was modeled in different orientations 21 in order to understand the mechanism of H2O2 adsorption ( step 1 in Scheme 1 ), potential H2O2 decomposition, and metal leaching.