Abstract
Effect of calcination, reoxidation and heating rate in an inert atmosphere on the subsequent reducibility of fresh and spent Pt/Al 2O 3 and Pt-Re/Al 2O 3 have been investigated. Catalytic activity was measured in the conversion of n-hexane. It has been established by using temperature programmed reduction (TPR) that after calcination the average oxidation state of the metals in Pt/Al 2O 3 and Pt-Re/ Al 2O 3 catalysts is 2.5 and 4.5 respectively. On reoxidation of the reduced catalysts at 720 K, the average oxidation state was 2 and 3.5, respectively, and TPR showed the presence of a separate platinum phase in the Pt-Re/Al 2O 3 catalysts. A separate Re phase was also observed in the spent Pt-Re/Al 2O 3 catalysts. In the pretreatment procedure the effect of sulphidation on the catalysts and its ability to retain sulphide was also investigated by a radioactive method using 35S labelled H 2S. Pt-Re/Al 2O 3 retains sulphide very strongly and its affect very much resembles to that of carbon formed at ageing. The behaviour of spent and fresh catalysts was also compared.
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.
