Carbon nanofibers were synthesized on graphite felt substrate by catalytic decomposition of ethane. The preshaped material was efficiently used as catalyst support for the active phase NiS2 in the direct oxidation of H2S into elemental sulfur. The catalyst was extremely active, selective, and stable at 60 degrees C in a fixed bed reactor due to the high resistance of carbon nanofiber based catalyst to the solid sulfur loading. This is explained by the specific mode of sulfur deposition, involving the role of water in the sulfur transport and the hydrophobic nature of the support.