Structure, chemical composition, and reactivity correlations during the in situ oxidation of 2-propanol.

نویسندگان

  • Kristof Paredis
  • Luis K Ono
  • Simon Mostafa
  • Long Li
  • Zhongfan Zhang
  • Judith C Yang
  • Laura Barrio
  • Anatoly I Frenkel
  • Beatriz Roldan Cuenya
چکیده

Unraveling the complex interaction between catalysts and reactants under operando conditions is a key step toward gaining fundamental insight in catalysis. We report the evolution of the structure and chemical composition of size-selected micellar Pt nanoparticles (∼1 nm) supported on nanocrystalline γ-Al(2)O(3) during the catalytic oxidation of 2-propanol using X-ray absorption fine-structure spectroscopy. Platinum oxides were found to be the active species for the partial oxidation of 2-propanol (<140 °C), while the complete oxidation (>140 °C) is initially catalyzed by oxygen-covered metallic Pt nanoparticles, which were found to regrow a thin surface oxide layer above 200 °C. The intermediate reaction regime, where the partial and complete oxidation pathways coexist, is characterized by the decomposition of the Pt oxide species due to the production of reducing intermediates and the blocking of O(2) adsorption sites on the nanoparticle surface. The high catalytic activity and low onset reaction temperature displayed by our small Pt particles for the oxidation of 2-propanol is attributed to the large amount of edge and corner sites available, which facilitate the formation of reactive surface oxides. Our findings highlight the decisive role of the nanoparticle structure and chemical state in oxidation catalytic reactions.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Investigation of the Activity of Nano Structure Mn/γ-Al2O3 Catalyst for Combustion of 2-Propanol

This paper reports results of a study regarding the activities of nano structure Mn/γ-Al2O3 and γ-Al2O3 catalysts for oxidation of 2-propanol (as a model of volatile organic compound). Nanostructure of catalysts was revealed using XRD, SEM and TEM techniques. Catalytic studies were carried out in U-shaped packed bed reactor under atmospheric pressure and at the reaction temperature of 150- 500°...

متن کامل

Modeling the Surface Tension and the Interface of Ten Selected Liquid Mixtures: Correlation, Prediction, and the Influence of Using Partial Molar Volume

This work investigates the modeling of the surface tension and the interface of liquid mixtures. Nine binary liquid mixtures of (DMSO+alcohols), (2-Propanol+2,2,4-trimethylpentane), (Tetrahydrofuran+2-Propanol), (Tetrahydrofuran+2,2,4-trimethylpentane), and (ethano+glycerol) are considered. Additionally, one ternary liquid mixture of (Tetrahydrofuran+2-Propanol+2,2,4-trimethylpenta...

متن کامل

Chemical composition and the nutritive value of pistachio epicarp (in situ degradation and in vitro gas production techniques)

The nutritive value of pistachio epicarp (PE) was evaluated by in situ and in vitro techniques. Chemical analysis indicated that PE was high in crude protein (11.30%) and low in neutral detergent fiber (26.20%). Total phenols, total tannins, condensed tannins and hydrolysable tannins contents in PE were 8.29%, 4.48%, 0.49% and 3.79%, respectively. Ruminal dry matter and crude ...

متن کامل

A Kinetic Investigation into the In Situ Combustion Reactions of Iranian Heavy Oil from Kuh-E-Mond Reservoir

An efficient design of in situ combustion depends on accurate kinetic modeling of the crude oil oxidation. The kinetic triplet of the oxidation reactions of a heavy oil sample was investigated. Once the kinetic triplet is known, the kinetic equation would be deconvolved. The crude oil sample was obtained from Kuh-E-Mond reservoir, located in the southwest of Iran. The samples were analyzed usin...

متن کامل

Effects of electron beam, NaOH and urea on chemical composition, phenolic compounds, in situ ruminal degradability and in vitro gas production kinetics of pistachio by-products

The current study evaluated the effects of electron beam (EB; 10, 20, 30 and 40 kGy), urea and NaOH treatments on chemical composition, phenolic compounds, in vitro gas production and in situ ruminal degradability of pistachio by-product (PB). The EB decreased (p < 0.01) neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) contents...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Journal of the American Chemical Society

دوره 133 17  شماره 

صفحات  -

تاریخ انتشار 2011