Product distribution vs. time

Figure la shows the product distribution vs. time during the oxidation of succinic acid (43 mmol 1 ) at 190°C and a total pressure of 5 MPa (partial oxygen pressure 0.7-0.8 MPa) on Ig of 5% Ru/C catalyst. Figure lb gives the TOC removal and the eorresponding pH profile for the same experiment. 

As a model for cracking of alkanes, the reaction of 2-methylpentane (MP) over SbFs-intercalated graphite has been studied in a flow system, the hydrocarbon being diluted in a hydrogen stream. A careful study of the product distribution vs time on stream showed that propane was the initial cracking product whereas isobutane and isopentane (as major cracking products) appear only later. 

This result can only be explained by the jS-scission of the trivalent 3-methyl-4-pentyl ion as the initial step in the cracking process. Based on this and on the product distribution vs time profile, a general scheme for the isomerization and cracking process of the methylpentanes has been proposed (Scheme 5). ... 

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