CH4-SCR (selective catalytic reduction) catalyst taking waste vanadium-titanium denitration catalyst as raw material and preparation method of CH4-SCR catalyst

The invention discloses a CH4-SCR (Selective Catalytic Reduction) catalyst taking a waste vanadium-titanium denitration catalyst as a raw material and a preparation method of the CH4-SCR catalyst. According to the CH4-SCR catalyst, the waste vanadium-titanium denitration catalyst, diatomite and kaolin are compounded to prepare a CH4-SCR catalyst carrier, and a gallium-aluminum composite oxide (GaAlOx) is taken as a catalytic active component. The method comprises the following steps: preparing a carrier from a waste vanadium-titanium denitration catalyst, diatomite and kaolin through processes such as crushing, burdening and calcining, preparing a gallium-aluminum composite oxide precursor into a colloidal solution, dipping the carrier into the gallium-aluminum composite oxide precursor colloidal solution, and drying and calcining to obtain the CH4-SCR catalyst. The CH4-SCR catalyst not only can realize harmless treatment of the waste vanadium-titanium denitration catalyst, but also can realize high-added-val