Reaction pathways of halocarbon catalytic oligomerization

The hydrodechlorination of CH2Cl2, CHCl3, and their mixtures catalyzed by a Pt-Co/C catalyst has been investigated in an effort to elucidate the chemistry associated with the generation of hydrocarbon oligomerization products. Both saturated and unsaturated C2 + hydrocarbons were observed with all three reaction mixtures, with the selectivity following the order CH2Cl2 + H2 < CHCl3 + H2 < CH2Cl2 + CHCl3 + H2. The results suggest that C2 + paraffins are formed by means of the alkyl mechanism of hydrocarbon chain growth; whereas, the alkenyl mechanism is responsible for olefin formation.

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► Catalyzed reactions of CH2Cl2 and CHCl3 with H2 results in C2 + hydrocarbons.
► Mainly paraffins constitute the products of the CH2Cl2 oligomerization.
► Olefins prevail among oligomerization products with the CHCl3 + H2 feed.
► Different mechanisms of C―C chain growth for CH2Cl2 and CHCl3 dechlorinations.