The invention discloses a method for preparing a 1,2-
dichlorobenzene waste gas removal catalyst. The method comprises the following steps: placing
chromium-containing waste liquid in a sealed container, and aerating
carbon dioxide into the container, so as to obtain carbonated
chromium-containing waste liquid; adding
ferrous carbonate into the carbonated
chromium-containing waste liquid, and performing stirring while sealing, so as to obtain reduced carbonated chromium-containing waste liquid; finally, adding
calcium hydroxide into the reduced carbonated chromium-containing waste liquid, performing stirring under a sealed condition until a precipitate is produced, performing
solid-liquid separation, and performing
thermal decomposition on the
solid in an
atmosphere furnace, thereby obtaining the 1,2-
dichlorobenzene waste gas removal catalyst. According to the method disclosed by the invention, the 1,2-
dichlorobenzene waste gas removal catalyst is prepared by recycling the chromium-containing waste liquid, so that harmless disposal of the chromium-containing waste liquid is saved, and a new idea is provided for disposal and utilization of the chromium-containing waste liquid; the problem that
carbon monoxide pollution is produced by the traditional 1,2-dichlorobenzene waste gas in a
catalytic oxidation process is solved.