Abstract
<p>The effect of ball milling on the structure and surface reactivity of the Mn-doped vanadium phosphorus oxide (V–P–O) catalyst is discussed. Mn-doped VOHPO<sub>4</sub>·½H<sub>2</sub>O precursor was prepared via organic method. The precursor was ball milled in isopropyl alcohol using agate balls for 60 min at 800 rpm. XRD, BET surface area measurements, SEM, O<sub>2</sub>-TPD, H<sub>2</sub>-TPR and TPD of NH<sub>3</sub> were used to characterize properties of the final catalysts. The results revealed that mechanical treatment of Mn-doped V–P–O catalyst increased surface area as well as reduced particle size of the material. Furthermore, process also increased exposure of (001) crystallographic plane of VOHPO4·½H<sub>2</sub>O precursor. The secondary structure of the milled material is also lost. The total amount of oxygen desorbed (from O<sub>2</sub>-TPD) and removed (by H<sub>2</sub>-TPR) from milled material is higher compared to the unmilled one. The surface acidity of the catalyst was also increased after milling process, as evidenced by lower desorption temperature and higher total amount of the ammonia desorbed.</p>
Highlights
It is well known that the vanadium phosphorus oxide (V–P–O) is the only catalysts commercially used for the partial oxidation of n-butane to maleic anhydride (MA) [1]
Ji et al [10] have prepared V–P–O catalysts doped by combined components (Zn+Zr+Mo, Zr+Zn and Zr+Mo) through impregnation and followed by ball milling process. They found that catalyst modified with combination of Zr, Mo and Zn elements and subjected to ball milling process showed increased in the surface area of both precursor and final catalyst
The process of ball milling has increased the values of full width at half maximum (FWHM) of the materials, indicating that the crystallite size is decreased whereas the microstrain is increased
Summary
It is well known that the vanadium phosphorus oxide (V–P–O) is the only catalysts commercially used for the partial oxidation of n-butane to maleic anhydride (MA) [1]. This observation was agreed by Fait et al, [9] which reported that a decreased particle size and increased of microstrain in the VOHPO4· 1⁄2H2O precursor would improved catalytic properties of the V–P–O catalysts. They found that catalyst modified with combination of Zr, Mo and Zn elements and subjected to ball milling process showed increased in the surface area of both precursor and final catalyst.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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.
