Hydroisomerisation of n-heptane over Pt/sulfated zirconia catalyst at atmospheric pressure

• [Display omitted] Route a: n-heptane conversion to isoheptane.•Route b: isoheptane conversion to cracked products.•The catalyst gave ≥90% selectivity to iso-heptane at low temperature.•The reaction network was explained using deplot hypothesis. n-Heptane conversion was studied over Pt/sulfated zirconia catalyst using a fixed bed reactor at atmospheric pressure. Reaction temperature was varied between 453 and 723 K and the weight hourly space velocity was varied between 0.02 and 0.15 h−1. The catalyst gave 96% selectivity to iso-heptane at ca. 9% conversion level (453 K). Furthermore, cracked products were only formed at higher conversions level through consecutive reaction routes. The only mono-branched product was 3-methyl hexane, while 2,3-dimethylpentane and 2,2-dimethylpentane were the other isomers. Under all conditions, selectivity to 2,3-dimethylpropane dominates because 2,2-dimethylpentane was cracked to iso-butane and propane. Both high temperature and low space velocity increase the conversion but lead to a significant decrease in isomer selectivity.