An extended mechanism including high pressure conditions (700bar) for toluene pyrolysis

Thermal cracking of n-butylbenzene at high pressure: Experimental study and kinetic modelling

“…The bimolecular initiations between two n-butylbenzene molecules which imply a loss of aromaticity, were considered ( Fig. 4), because a previous study on the pyrolysis of toluene highlighted their importance [20]. Therefore, the kinetic parameters A and n were taken from [20], and the activation energy, which corresponds to the enthalpy of reaction in this case, was calculated by theoretical calculations at the CBS-QB3 level of theory.…”

“…That is why several experimental studies of thermal cracking of alkylbenzene can be found in the literature: alkylbenzenes are taken as model compounds of the aromatic fraction ( [12], [13] and [14]) or as model compounds of asphaltenes [15] or even of heavy oils [16]. A few studies include detailed kinetic modelling at high pressure ( [17], [18], [19], [20], [21] and [22]) or in supercritical water conditions [22]. In those studies, pressure is usually in the range of 0.2-14 MPa and temperature is usually greater than 673 K, except for the studies [18] and [20] conducted at 70 MPa and temperatures lower than 623 K. Main products of the pyrolysis of alkylbenzenes (CnH2n+1-C6H5) are usually grouped into two pairs: toluene and Cn-1H2n/Cn-1H2n-2 as well as ethylbenzene and/or styrene and Cn-2H2n-2 ( [14] and [15]).…”

“…A few studies include detailed kinetic modelling at high pressure ( [17], [18], [19], [20], [21] and [22]) or in supercritical water conditions [22]. In those studies, pressure is usually in the range of 0.2-14 MPa and temperature is usually greater than 673 K, except for the studies [18] and [20] conducted at 70 MPa and temperatures lower than 623 K. Main products of the pyrolysis of alkylbenzenes (CnH2n+1-C6H5) are usually grouped into two pairs: toluene and Cn-1H2n/Cn-1H2n-2 as well as ethylbenzene and/or styrene and Cn-2H2n-2 ( [14] and [15]).…”

“…This paper aims to construct and validate a detailed and robust kinetic model for the thermal cracking of n-butylbenzene. Shorter alkylbenzenes like toluene [20] and longer alkylbenzenes like ndecylbenzene [18] were already exhaustively studied, contrary to n-butylbenzene [14]. For this purpose, new experimental data has been obtained from confined pyrolysis experiments (sealed gold cells [23], [24] and [25]), for a pressure characteristic of deep reservoirs (70 MPa) and for large temperature (583-623 K) and conversion (0.7-62 %) ranges.…”

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

“…These reactions are favored by high pressure and they were also investigated in many studies (e.g. [18], [23], [57], [58]); • unimolecular initiations by dissociation of C S bonds in thiols;…”