以马鞍山钢铁集团南山矿铁矿石尾矿为主要原料制备无载体催化剂，对其进行了XRF, BET和XRD表征，并于电加热石英玻璃管固定床中实验研究了催化剂对NH3还原NO的催化活性. 结果表明，用铁尾矿所制催化剂在反应温度500?600℃下具有良好的催化活性，600℃时催化还原率达97.5%，且粒径越小催化还原率越高；氧含量对催化还原率有较大影响，350℃时增加氧含量可提高催化还原率，500℃时增加氧含量会降低催化还原率；氧化铁作为主要活性组分，在催化剂中含量越高催化还原率越高，但氧化铁高温时易烧结，会降低催化还原率.

Unsupported catalyst was prepared by iron ore tailing selected from Nanshan mine of Ma?anshan iron & steel company limited. The catalysts were characterized by XRF, BET and XRD techniques. Experiments of catalytic reduction of NO over catalyst with NH3 were carried out in a quartz glass fixed-bed reactor. The results showed that the catalyst prepared by iron ore tailing presents a good catalytic activity for NO reduction at 500?600℃. The catalytic reduction rate can reach to 97.5% at 600℃. Moreover, the smaller the particle size, the higher the catalytic reduction rate. Increasing oxygen content can increase catalytic reduction rate of NO at 350℃. However, high oxygen content can decrease catalytic reduction rate of NO at 500℃. The higher the iron oxide content, the higher the catalytic reduction rate. But at high temperature, sintering of iron oxide can decrease the catalytic reduction rate.