Air pollution has become a major concern in recent years in China. The State Council of China issued the "Air Pollution Prevention and Control Action Plan" in 2013. According to the plan, natural gas should be used more efficiently and newly extracted natural gas should give exclusive priority to living consumption or replace coal combustion". Since 2016, Chinese provinces have been promoting the "Coal to Gas Shift" project rapidly and steadily. It is estimated that the natural gas consumption in China will exceed 2 500×108m3in 2020 and 4 000×108m3in 2030.
Compared with coal combustion, the exhaust of natural gas boilers possess less SO2, but the emission of NOxin the exhaust is not to be underestimated. In addition, the exhaust in gas boilers are low in temperature and contain much higher H2O that will inhibit the activity of a Selective Catalytic Reduction (SCR) catalyst to deal with NOxemission. Thus the NH3-SCR catalysts used for gas boilers must possess excellent low temperature performance and H2O resistance. Therefore, finding low temperature NH3-SCR catalysts for gas boiler exhaust will have practical and economic significance.
The “Air and Biomass Catalysis Group” of Tianjin University Environmental Science and Engineering School made great progress in the field of natural gas combustion exhaust treatment. A co-precipitation method was used to design and synthesize the Mn-based novel catalysts for natural gas combustion exhaust treatment.
This kind of catalyst helps solve the problem of NOxtreatment by SCR catalysts given the condition of high H2O and low temperatures, having great theoretical and application value.
Their research results “Novel MnaZrbCrcOx catalysts for low temperature NH3-SCR derived from high H2O content flue gas via natural gas combustion” and “Improved low-temperature activity and H2O resistance of Fe-doped Mn-Eu catalysts for NO removal by NH3-SCR” were published in the international environmental journals ofChemical Engineering JournalandChemcatchem, respectively.
By Mingyu Guofrom the School of Environmental Science and Engineering
Edited by Eva Yin & Doris Harrington
