Iron-based SCR (Selective Catalytic Reduction) catalyst and preparation method thereof

The invention discloses an SCR (Selective Catalytic Reduction) catalyst containing synthetic zeolite and iron, and particularly relates to an SCR catalyst which always has an NOx purifying property in a low-temperature region after being subjected to relatively long-term action of hot water and relatively long-term action of sulfur oxides. A preparation method of the SCR catalyst, disclosed by the invention, comprises the following steps: crystallizing a hydrogenised synthetic zeolite with maximal oxygen cycle number of 8-12 and a three-dimensional structure by using a mixing procedure, and blending with a ferric nitrate (III) water solution or ferric chloride (III) water solution with a pH value of 0.1-0.7 to obtain the SCR catalyst without a filtering procedure and a cleaning procedure.