Coke formation in the pyrolysis and oxidative pyrolysis of methane and methyl chloride

Thermal cracking of CH3Cl leads to auto-catalysis of deposited coke

“…This result is in the range of activation energy experimentally determined for the thermal cracking: 305 and 501 kJ/mol. 18 Moreover, the result is close to the dissociation energy of the C-H bond and is lower than the one of C-Cl in CH 3 Cl, 339 and 423 kJ/mol respectively. 19 Such result is consistent with a homolytic bond breaking, leading to the radicals formation.…”

“…between 747 and 987 °C, at 1 atm). 18 However, they did not investigate the nature of the catalyst. To our best knowledge, such catalytic activity at 400 °C of coke formed during the CH 3 Cl cracking was not previously reported.…”

Suppression of Coke Formation in the Steam Cracking of Alkanes: Ethane and Propane

“…It should be noted that at 2.5 cm 3 /s the flow regime in the reactor would be laminar and would correspond to a nominal residence time of 15 s and about 1.5 s to cross the quartz coupon. This residence time was determined by taking into account the volume occupied by the baffle (Tran, 1992). Overall reactant conversions, measured separately by gas chromatography at the exit of the reactor, were generally in the range 2-5%.…”

“…In Figure 1 the experimental apparatus used to study the formation of coke during the steam cracking of ethane and propane is illustrated. This apparatus is a modified version of the setup used previously in the pyrolysis and oxidative pyrolysis of methane and methyl chloride (Tran and Senkan, 1994). The main component of the experimental system is a Cahn 131 thermogravimetric analyzer (TGA, Madison, WI) that has a detection sensitivity of 1 µg.…”

“…× 32.5 cm long quartz reactor that was vertically placed inside a single-zone electrical furnace. The heating elements inside the furnace span a distance of about 15 cm, thereby allowing the establishment of a nearly isothermal central zone of about 2 cm in length in which the coupons were placed (Tran and Senkan, 1994). Deionized (DI) water or water containing 1 ppm H 2 PtCl 6 additive (ATG Inc., Monrovia, CA) was pumped using a high-precision metering syringe pump (ISCO-2600 with Series D controller, Lincoln, NE) and was vaporized in an electric furnace maintained at 400 °C.…”