Influencing factors and mechanism of catalytic oxidation at low temperature for NO removal by activated coke

In order to study the catalytic oxidation characteristic of activated coke at low temperature,long period bench test was adopted in this study.The proportion of compounded modeled flue gases components came from operational pulverized coal industry boiler. Emphasis was placed on reaction temperature,oxygen concentration,air-speed and SO_2 concentration which had a great importance in denitration efficiency.Meanwhile,the infrared spectroscopic analysis and thermogravimetric analysis had been carried out on the fresh activated coke and deactivation coke.The results show that when the temperature increases from 50 ℃ to 90 ℃,the denitration efficiency will obviously decline and the valid time for denitration will decline to 2.3 hours from 81 hours.When the oxygen concentration goes up to 10% from 0,the valid time will rise to 35 hours from 0.6 hours.And the valid time will decrease to 0.26 hours from 15 hours,after the airspeed increasing to 2 500 h~(-1) from 500 h~(-1).In addition,the valid time will decline to 1.6 hours from 15 hours with the SO_2 concentration up to 200× 10~(-6) from 0.The infrared spectroscopic and thermogravimetric analysis also indicate that NO could be catalytically oxidized to NO_2,which is significantly adsorbed by activated coke at low temperature.