Fuel Processing Technology, Vol.191, 121-128, 2019
Nitrogen-rich hierarchical porous carbon nanofibers for selective oxidation of hydrogen sulfide
Nitrogen-rich hierarchical porous carbon nanofibers (N-PCNFs) with highly efficient catalytic activity for the oxidation of hydrogen sulfide (H2S) at low temperature has been constructed through a modified electrospinning technology, using polyacrylonitrile (PAN) and zeolitic imidazolate framework (ZIF-8) as both carbon and nitrogen precursors. The specific surface area, doped nitrogen content and the ratio of micropores to mesopores of N-PCNFs can be readily adjusted by tuning the mass ratio of ZIF-8/PAN, the carbonization temperature combined with chemical activation treatment. After impregnated by sodium carbonate, the as-made N-PCNF catalysts exhibit an ultrahigh activity and superior sulfur capacity (the breakthrough sulfur capacity is up to 3.57 g H2S/g cat.) for the transformation of H2S into elemental sulfur at room temperature. The enhanced performance of N-PCNF catalysts for the selective oxidation of H2S has been demonstrated synergistically deriving from the nitrogen doping and the abundant micropores and mesopores in the one-dimension structural nanocarbons. The rational approach would make a great implication for the design of carbon nanocomposites for the efficient conversion of H2S.