I was doing some conversions from my book and I was stuck on one question, where I need to convert propane to prop-1-ene. Help me with the concept behind it.

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    $\begingroup$ As to your query. There are probably hundreds of possibilities at varying conditions to convert alkanes to alkenes. This question is therefore very broad and you should probably try to narrow it down to add context and add your own research on possible reactions. Otherwise its score will drop, or it gets closed (or both) and you won't get an answer. The easiest (but also very unspecific) I can think of is alkane -> alkyl halide -> alkene. $\endgroup$ – Martin - マーチン Jun 20 '17 at 6:15

There are numerous methods to convert propane to prop-1-ene. Some of them are:

  1. Using boron nitride($\ce{BN}$)

The exothermic oxidative dehydrogenation of propane reaction to generate propene has the potential to be a game-changing technology in the chemical industry. Here, we report that hexagonal boron nitride (h-BN) and boron nitride nanotubes (BNNTs) exhibit unique and hitherto unanticipated catalytic properties resulting in great selectivity to olefins. As an example, at 14% propane conversion, we obtain selectivity of 79% propene and 12% ethene, another desired alkene. Based on catalytic experiments, spectroscopic insights and ab initio modeling, we put forward a mechanistic hypothesis in which oxygen-terminated armchair BN edges are proposed to be the catalytic active sites.

  1. Using cobalt and magnesium molybdates

Catalytic performances of various metal molybdates were tested in the oxidative dehydrogenation of propane to propene with molecular oxygen under an atmospheric pressure. Most of the molybdates tested promoted the selective oxidative conversion of propane to propene and among them cobalt and magnesium molybdates were found highest in the activity and selectivity. It was also found that their catalytic activities were highly sensitive to the catalyst composition, and it turned out that $\ce{Co_{0.95}MoO_x}$ and $\ce{Mg_{0.95}MoO_x}$ catalysts which have slightly excess molybdenum showed the highest activity in the oxidative dehydrogenation of propane. Under the optimized reaction conditions, higher reaction temperatures and lower partial pressures of oxygen, these catalysts gave 60% selectivity to propene at 20% conversion of propane. Since the molybdates having the surface enriched with molybdenum oxide tended to show high activity for the propane oxidation, surface molybdenum oxide clusters supported on metal molybdate matrix seem to be the active sites for the selective oxidative dehydrogenation of propane.

  1. Using gallium oxide

Dehydrogenation of propane to propene in the presence or absence of $\ce{CO2}$ over four polymorphs of gallium oxide was investigated. $\ce{β-Ga2O3}$ exhibits the highest activity among the polymorphs, and it is even more active than chromium oxide catalyst in the presence of $\ce{CO2}$. H2-TPR and XPS studies show that gallium oxide is hardly reduced below 600 °C. The dehydrogenation reaction is suggested to proceed through a heterolytic dissociation reaction pathway, and it is enhanced by $\ce{CO2}$ because of the existence of the reverse water gas shift reaction and the Boudouard reaction. The high catalytic activity of $\ce{β-Ga2O3}$ is probably associated with an abundance of surface medium-strong acid sites related to the coordinatively unsaturated $\ce{Ga^3+}$ cations and the conjugated effect of proton and oxide. Furthermore, increasing the reaction temperature facilitates the activation of $\ce{CO2}$ over $\ce{β-Ga2O3}$. The promoting effect of $\ce{CO2}$ on $\ce{β-Ga2O3}$ catalyst is more evident above 550 °C.

  1. Using platinum and platinum-gold alloys

The rates of dehydrogenation of propane to propene over platinum and very dilute platinumin-gold alloys have been measured. In the composition range of 0.5–14.0 atom % platinum, the rates per unit surface area of the alloy powders vary linearly with the bulk platinum concentration in the alloys. From this it is concluded that only one platinum atom is involved in the rate-determining step.

For both platinum and the alloys, activation energies of some 29 ± 2 kcal/mole were measured. The reaction rate order in hydrogen, however, is different. It is proposed that propane dehydrogenation over platinum and over the alloys occurs via the same reaction mechanism, namely, dissociative chemisorption of propane on a single platinum atom to which two adsorption sites are associated, one of which carries a hydrogen atom. The subsequent conversion of the propyl radical into π-bonded propene via β-hydrogen elimination appears to be rate determining. The last step, desorption of π-bonded propene, has a comparatively low activation energy. The difference in negative reaction order, with respect to hydrogen, between platinum and its diluted alloys reflects a lower steady-state θH on Pt atoms surrounded by Au atoms vis-à-vis Pt atoms on a Pt surface.

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