Excellent stability of Pd/mpg-C3N4 in catalytic hydrodebenzylation of 2,4,6,8,10,12-Hexabenzyl-2,4,6,8,10,12- hexaazaisowurtzitane (HBIW).

Pd/mpg-C 3 N 4 was prepared by depositing palladium nanoparticles on mpg-C 3 N 4 using chemical reduction method, and was firstly used for the catalytic hydrogenolysis of HBIW in hydrogen under atmosspheric pressure. Due to the unique "nitrogen ring" and the larger specific surface area of the mpg-C 3 N 4 , Pd/mpg-C 3 N 4 showed a better performance than Pd/C and the unprecedented recyclability in the conversion of HBIW to TADBIW. Such results do not only promote the application of HNIW but also enlighten the design of heterogeneous catalysts for hydrodebenzylation. [Display omitted] • Although Pd/mpg-C 3 N 4 was widely applied in hydrogenation, it was reported in the catalytic hydrogenation of debenzylation for the first time. • Pd/mpg-C 3 N 4 exhibited higher performance than Pd/C in the hydrodebenzylation of HBIW in terms of both recyclability and the activity. • Pd/mpg-C 3 N 4 displayed the unprecedented recyclability in the conversion of HBIW into TADBIW, which is significant for the application of HNIW. The low stability and poisoning of the palladium-based catalysts in the debenzylation of HBIW elevated the cost of the hydrogenolysis, and thus restricted the application of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW). To address this problem, Pd/mpg-C 3 N 4 was prepared by depositing palladium nanoparticles on mesoporous graphite carbon nitride (mpg-C 3 N 4), and used for the catalytic hydrogenolysis in the conversion of HBIW to TADBIW under the atmospheric pressure. After optimizing the reaction condition and the usage amount, the highest yield of 81.7 % was obtained at 45℃ after reaction for 8 h when the ratio of palladium to HBIW was 1%. A yield of 74 % was obtained when the ratio of palladium to HBIW was 0.4 %. More importantly, Pd/mpg-C 3 N 4 can be recycled unprecedently for three times in the conversion of HBIW to TADBIW while preserving the reasonable activity. Such results should benefit for promoting the application of HNIW and also the design of the heterogeneous catalysts for hydrodebenzylation. [ABSTRACT FROM AUTHOR]