Thermal reactions between alkanes and H2S or thiols at high pressure

Pyrolysis mechanism of the n-octane/H2S mixture at 70MPa and 603–623K

“…Although it was experimentally not possible to precisely measure the conversion of n-octane, we already suspected by a rough estimation that the pyrolysis of n-octane is inhibited by H 2 S [9]. The kinetic model allows investigating this issue more precisely.…”

“…While the mineral geochemistry of sulfur is among the most studied topics in geology, the role of sulfur in reactions involving hydrocarbons has also been investigated over the past decade, but mostly, with regards to the interactions between mineral sulfur species (elemental sulfur, sulfates) and hydrocarbons -the so-called thermochemical sulfate reduction, TSR [5][6][7][8]. Very few papers have actually investigated the direct interactions of H 2 S with hydrocarbons [9] in reservoir conditions, while no kinetic studies have been usually conducted.…”

“…H 2 S can be a dominant gas in carbonate petroleum reservoirs [28][29][30][31][32][33][34] and its abundance is primarily explained by thermochemical sulfate reduction (TSR) [35][36][37][38][39][40][41]. However, little work on the effects of H 2 S on alkane pyrolysis (a dominant hydrocarbon class in petroleum [42]) was published [9]. The purposes of this paper are (i) the construction of a detailed kinetic model for the pyrolysis of the n-octane/H 2 S mixture, on the basis of the experimental data previously published [9]; and (ii) the explanation of the inhibition effect of H 2 S on the n-octane pyrolysis observed at 603-623 K under 70 MPa.…”

“…4); • RHT reactions (radical hydrogen transfers, Fig. 5); • cross-terminations between the radicals derived from n-octane and H 2 S, and terminations of the new radicals formed by the cross-reactions.More examples of reactions are given in Nguyen et al[9]. Concerning the kinetic parameters of the sulfur compounds, only few Examples of ispo-addition of an octyl radical to H2S and of H • Examples Examples of decomposition by ␤-scission.…”

Influence of H2S on the thermal cracking of alkylbenzenes at high pressure (70 MPa) and moderate temperature (583–623 K)

“…In experimental studies, much attention has been paid to the formation of H 2 S and sulfur compounds arising from reaction within the water phase or at the interface with the hydrocarbon phase. Very few studies deal with the consequence of a direct reaction of H 2 S on the hydrocarbons ( [14] [15] [16] [17] [18]) within the organic phase or at the oil-gas interface, especially in the absence of TSR conditions. Yet, such information would be of great value since an improved understanding of the fate of H 2 S and organic sulfur compounds would be highly beneficial for petroleum exploration, exploitation of high sulfur petroleum fields, recovery of heavy oil by steam injection, enhanced recovery by gas injection and sequestration of H 2 S in depleted petroleum reservoirs.…”