Abstract: A direct decomposition device for hydrocarbons for directly decomposing hydrocarbons into carbon and hydrogen includes a rector containing a catalyst including a plurality of metal particles with an iron purity of 86% or more. The reactor is configured to be supplied with a raw material gas containing hydrocarbons.

Abstract: Provided are a denitration catalyst regeneration method and a denitration catalyst regeneration system, which are capable of recovering denitration performance to a high level and reducing the SO2 oxidation rate of a catalyst. A denitration catalyst regeneration method according to the present invention includes: a chemical solution cleaning step for immersing a denitration catalyst in a chemical solution containing a fluorine compound and an inorganic acid; a step for extracting the denitration catalyst from the chemical solution; and a finish washing step for washing the denitration catalyst extracted from the chemical solution with a finish cleaning solution containing an organic acid.

Abstract: Provided are: a cleaning agent for a denitration catalyst; and a denitration catalyst regeneration method and a denitration catalyst regeneration system which make it possible to efficiently remove matter adhering to a surface of a catalyst and to greatly restore catalytic performance. The regeneration method includes: a prewashing step (S12) of washing a denitration catalyst with water; a liquid agent cleaning step (S14) of immersing the denitration catalyst washed with water in a liquid agent containing an inorganic acid and a fluorine compound; a step of recovering the denitration catalyst from the liquid agent; and a finish washing step (S16) of washing the denitration catalyst recovered from the liquid agent with a finish cleaning liquid which is water or sulfamic acid-containing water.

Abstract: Provided are: a cleaning agent for a denitration catalyst; and a denitration catalyst regeneration method and a denitration catalyst regeneration system which make it possible to efficiently remove matter adhering to a surface of a catalyst and to greatly restore catalytic performance. The regeneration method includes: a prewashing step (S12) of washing a denitration catalyst with water; a liquid agent cleaning step (S14) of immersing the denitration catalyst washed with water in a liquid agent containing an inorganic acid and a fluorine compound; a step of recovering the denitration catalyst from the liquid agent; and a finish washing step (S16) of washing the denitration catalyst recovered from the liquid agent with a finish cleaning liquid which is water or sulfamic acid-containing water.

Abstract: Provided is a method for producing a NOx removal catalyst for high-temperature exhaust gas, comprising: calcining a mixture comprising ZrO2 and TiO2 with a ZrO2 content ratio of 15% by weight to 55% by weight at 500±15° C. to obtain a composite oxide support; and supporting tungsten oxide on the composite oxide support, followed by calcination at 650±15° C. to obtain a powder catalyst.

Abstract: Provided is a method for producing a NOx removal catalyst for high-temperature exhaust gas, comprising: calcining a mixture comprising ZrO2 and TiO2 with a ZrO2 content ratio of 15% by weight to 55% by weight at 500±15° C. to obtain a composite oxide support and supporting tungsten oxide on the composite oxide, support, followed by calcination at 650±15° C. to obtain a powder catalyst.