The calcination process of the alumina industry usually produces nearly 10 000 mg/m3 CO in the flue gas during the combustion process due to low temperature or low excess air coefficient. Direct emissions not only causes energy waste but also causes harm to the local atmosphere. To explore the industrial application feasibility for catalytic elimination of CO from flue gas in alumina calcination, the manganese-cerium particulate industrial catalysts were prepared by co-precipitation method, and the pilot application study with flue gas volume of 1000 Nm3/h was carried out in an aluminum company of Shandong Province. The pilot test results showed that under the condition of low sulfur (<10 mg/m3), when the inlet temperature was 170℃, the CO removal rate was 80%~85%, and the removal rate was above 90% when the temperature was above 200℃. The catalyst was used in the pilot test to run continuously for 500 h at the inlet temperature of 190~200℃. It was found that there was no significant decrease in activity as a whole, indicating that the manganese-cerium catalyst had good stability in the purification of CO gas under actual working conditions. After 500 h of pilot-scale catalyst operation, the catalyst samples at different positions of the fixed bed were analyzed, and it was found that the catalyst performance at the flue gas inlet decreased slightly. The characterization results of typical samples such as XRD, TG, BET, SEM-EDS, and H2-TPR showed that the crystal diffraction peak of the catalyst sample at the flue gas inlet was enhanced, the specific surface area was decreased, and the sulfur deposition was increased, indicating that the local heating sintering and sulfur deposition were the main reasons for the partial deactivation of the catalyst.