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 article, the authors investigated the catalytic epoxidation of propylene with aqueous hydrogen peroxide over four Ti-containing silicates, namely titanium silicalite (TS-1), a TiO2-SiO2 xerogel, Ti-MCM-41, and a TiCl4-modified HZSM-5 zeolite.
TL;DR: In this article, the effect of solvent on the epoxidation of propylene with H 2 O 2 over TS-1 has been investigated, and the spent catalysts were characterized by TG analysis and FT-IR spectra.
TL;DR: In this article, the performances of Nb2O5-SiO2 catalysts prepared by sol-gel technique in the epoxidation of soybean oil with hydrogen peroxide have been investigated.
TL;DR: In this paper, Nb- and W-incorporated KIT-6 materials with aqueous hydrogen peroxide (H2O2) as the oxidant and methanol as solvent were investigated under mild operating conditions (35 °C and 50 bar).
TL;DR: Significant ethylene epoxidation activity was observed over niobium (Nb) incorporated mesoporous silicate materials Nb-KIT-5, NbMCM-48, and NbTUD-1, with hydrogen peroxide (H2O2) as oxidant and methanol (MeOH) as solvent under mild operating conditions (35°C and 50 ¼ bar) as mentioned in this paper.
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.