Abstract
Platinum supported on ceria and zirconia was prepared through different preparation methods: Coprecipitation (CP), spray drying (SD), and flame spray pyrolysis (FSP). The catalysts were characterized by XRD, TPR, N2 adsorption, and H2 chemisorption, and the water–gas shift activity in the range 190–310 °C and initial stability at 300–310 °C were tested. Although the spray-dried Pt/CeO2/ZrO2 catalyst shows the highest initial activity, it deactivates rapidly at 300 °C and levels out at similar activity as the coprecipitated Pt/CeO2 and Pt/CeO2/ZrO2 within a few hours. Flame spray pyrolysis appears to be a promising preparation method concerning the stability of catalysts, although the initial activity is rather poor. High activity is related to high Pt dispersion, low reduction temperature, and small support particles. The support particle size is also much affected by the preparation method.
Highlights
IntroductionThe water–gas shift (WGS) reaction has been an important step in industrial hydrogen production from hydrocarbons since the early 1940s: CO + H2 O ↔ CO2 + H2
The water–gas shift (WGS) reaction has been an important step in industrial hydrogen production from hydrocarbons since the early 1940s: CO + H2 O ↔ CO2 + H2∆H298 = −41.2 kJ mol−1 (1)Recently, there is a renewed interest in the reaction because of its importance in the production of hydrogen feed with a low CO level for fuel cell applications [1]
It is shown that the preparation method is of importance concerning the properties of the Pt-based catalysts, and thereby the water–gas shift activity
Summary
The water–gas shift (WGS) reaction has been an important step in industrial hydrogen production from hydrocarbons since the early 1940s: CO + H2 O ↔ CO2 + H2. Precious metal catalysts are stable at higher temperatures; they are nonpyrophoric and more tolerant of catalyst poisons such as sulfur. Ceria provides interesting support for precious metals, which are not oxidized by water and have, in general, poor WGS activity. Flame pyrolysis andmethods spray drying are expected methods catalysts well [11,12,13,14]. Flame spray pyrolysis andspray spray drying are that are that arehigh expected to area give catalysts high surface catalysts withactive finelymetal. The short time at residence time at high-temperature resultsofinsmall the formation of small particles, and precursor the homogeneous high-temperature results in the formation particles, and the homogeneous solution precursor solution yields homogeneous precipitate particles [15,16,17,18,19,20].are Such properties are considered yields homogeneous precipitate particles [15,16,17,18,19,20].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
