Conceptual processes for zeolite membrane based hydroisomerization of light alkanes

A zeolite membrane reactor concept for the hydroisomerization of n-hexane was applied experimentally. The results indicate separation selectivities with factors close to 20 for n-, mono- and dibranched components in a gas mixture, as well as nhexane conversions up to equilibrium values. The research octane number calculated for the product stream of the different experiments indicates numbers as high as 85. For the hydroisomerization of C7 alkanes, a concept of two reactors and a zeolite membrane was proposed and an industrial scale process was simulated. A high octane number product containing tribranched, and a part of dibranched, C7 isomers is predicted. Although the product yield was calculated to be only 24% of the process feed, there was an improvement in a research octane number from 57 for the feed to 92 for the product. Both processes show that the application of zeolite membranes in the hydroisomerization of light alkanes can results in a octane number higher, than in the "state of the art" processes. The membrane unit, however, is the main cost driver of the processes, thus, the economical feasibility of industrial scale light alkanes hydroisomerization processes using zeolite membranes is restricted to its further commercial development

Chemical conversion of NO and CO on catalysts based on cobalt or iron oxides.

Cobalt or iron oxides supported or not on zeolite Hbeta were prepared and evaluated in the reduction reaction of NO by CO in presence of O2, SO2 or H2O. XRD results evidenced the Hbeta structure and the formation of Co3O4 and Fe2O3. TPR-H2 analysis showed complete reduction of cobalt oxide at lower temperatures than for iron oxide. The catalysts are quite active and the activity depends on the reaction temperature. The highest conversions rates were observed for pure iron oxide, which can be a relatively low cost catalyst for reduction of NO by CO, with high selectivity towards the N2 formation