Reaction pathways of halocarbon catalytic oligomerization

Deactivation behavior of Pd/C and Pt/C catalysts in the gas-phase hydrodechlorination of chloromethanes: Structure–reactivity relationship

“…Although HDC of CMs has been investigated to a lesser extent than HDC of other organochlorine compounds, several publications have appeared in recent years including a number reporting on the deep gas-phase HDC of CMs over different supported metal catalysts [4,5,[8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. It is well known that precious metals are active catalysts for the hydrogenolysis of the carbon-chlorine bond [8,9].…”

“…Among them, palladium has been reported to be a very good option because of its high activity and selectivity to nonchlorinated products [21,25,26]. These studies report on the use of a wide variety of supports including SiO2 [5,10], Al2O3 [11][12][13], TiO2 [14][15][16] and carbon materials [4,[17][18][19][20][21][22][23][24]. However, in all cases where the performance as a function of time on stream has been evaluated, Pd catalysts have been shown to suffer severe and rapid deactivation.…”

“…In gas-phase HDC, deactivation of noble metal catalysts has been linked to poisoning by HCl and/or Cl, formation of carbonaceous deposits, loss of metal through the formation of volatile chlorides, and metal sintering [8,16,23,[27][28][29][30][31]. However, most of these studies do not address the HDC of CMs and very few publications refer to activated carbon-supported noble metal catalysts.…”

“…The nature of the support has been reported to have a significant influence on poisoning by HCl [14,32]. Several authors have proposed the formation of carbonaceous deposits, including chlorine in their constitution in many cases, as one of the main causes of deactivation of these catalysts [16,23,28,33,34].…”

Platinum Nanoparticles Supported on Activated Carbon Catalysts for the Gas-Phase Hydrodechlorination of Dichloromethane: Influence of Catalyst Composition and Operating Conditions

“…The use of catalysts based on different precious metals and acting as supports for the HDC of chloromethanes has been reported. Palladium, platinum, rhodium and ruthenium have been tested as active phases, while SiO 2 , Al 2 O 3 , TiO 2 and carbon materials have been tested as supports [10][11][12][13][14][15][16][17][18][19]. Palladium catalysts were the most active catalysts, with DCM conversions up to 100% and high selectivity toward non-chlorinated compounds (65-100%); however, they suffered severe and rapid deactivation.…”