The present work presents the synthesis, characterization and evaluation of a novel composite structure which integrates a network of platinum-based carbon nanotubes (CNT) with alumina. The catalyst obtained via a multi-step procedure involving CNT functionalization and platinum impregnation assisted by sonication, was evaluated processing n-heptane under reforming-relevant conditions. Characterization by TEM confirmed the dispersion of platinum over the multi-walled CNTs and the formation of the composite matrix. Catalytic testing was carried out in a fixed-bed reactor at 430 °C and 24 bar, with an H 2 :n-heptane molar ratio of 5 and LSHV of 1h -1 . The Pt-CNT/alumina catalyst exhibits favorable performance as a bifunctional isomerization catalyst. n-Heptane conversion increased from 61.2% at 160 min to 79.0% at 240 minutes on stream. The product slate was dominated by branched C7 isomers, which accounted for approximately 50 mol% selectivity at the highest conversion, with methylhexanes as the major isomerization products and dimethylpentanes as a smaller but persistent fraction. Aromatics, mainly toluene, appeared as secondary products, reaching approximately 6.5 mol% at higher conversion levels, accompanied by increased light cracking products. The comparative assessment shows that the contribution of this catalyst is not to outperform low-temperature hydroisomerization systems in absolute selectivity, but to maintain substantial branching activity under a higher-severity regime where cracking and aromatization inherently compete with skeletal isomerization. These results identify Pt-CNT/Al 2 O 3 as a promising composite platform for n-heptane upgrading and provide a basis for further optimization of chlorine level, metal-acid proximity, and composite architecture.
Robalino et al. (Fri,) studied this question.