from first principles PP-I-1

OP-III-21Dechlorination of Chlorohydrocarbons on Bulk Ni-Alloyed Catalysts:Mechanism of Carbon “Corrosion”Mishakov I.V. 1,2 , Bauman Yu.I. 1 , Vedyagin A.A. 1,21 Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia2 Novosibirsk State Technical University, Novosibirsk, Russiamishakov@catalysis.ruHeterogeneous gas-phase dechlorination of chlorinated hydrocarbons into valuable chemicalproducts (olefins [1] or carbon nanofibers – CNF [2]) is considered to be a prospective wayfor abatement of hazardous organochlorine wastes. Unlike other methods, including thermaloxidation, dechlorination doesn't lead to formation of secondary polluting substances, evenmore dangerous. Catalytic decomposition of chlorinated organic compounds usually results information of aggressive environment that requires the using of catalysts possessing theenhanced stability towards possible chlorination of metal particles. In this case the catalystdeactivation could be prevented by carrying out the process at temperatures above 500°С inthe presence of hydrogen in reaction gas feed.As we have recently reported [2], the catalytic particles (acting as sites for CNF growth)characterized with an optimal chemical composition and size can be spontaneously generatedin situ during the decomposition of chlorohydrocarbons on bulk Ni-based alloys used asprecursors. The interaction mechanism resulting in formation of high-performance selforganizingcatalyst is of a great interest. The process is schematically shown below.NiCr + 2HCl → Ni-Cl + Cr-Cl + H 2C x H y Cl z +NiCr →→ Ni-CNF + Cr + HClNi-Cl + H 2 ↔ Ni-H + HClFig. 1. Proposed scheme of catalytic destruction of chlorinated hydrocarbonson surface of bulk NiCr alloyThis study was financially supported by The Russian Ministry of Education and Science(President’s grant #MK-3711.2011.3) and by Department of Chemistry and MaterialsSciences RAS (project #5.2.2).References:[1] A. Śrębowata, W. Juszczyk, Z. Kaszkur, J.W. Sobczaka, L. Kępiński, Z. Karpiński, App. Catal.A 319 (2007) 181.[2] Yu.I. Bauman, I.V. Mishakov, R.A. Buyanov, A.A. Vedyagin and A.M. Volodin, Kinetics andCatalysis 52 (2011) 547.65