介孔TiO_(2)为载体的V-W-Ti催化剂及其脱硝性能

V-W-Ti Catalyst with Mesoporous TiO_(2) Support and Their Denitration Performance

针对燃煤电站锅炉烟气脱硝的主流工艺选择性催化还原技术(selective catalytic reduction,SCR),设计了具有介孔载体结构钒-钨-钛体系(V-W-Ti:V_(2)O_(5)-WO_(3)/TiO_(2))催化剂.研究了TiO_(2)载体的晶型、介孔结构、表面形貌对催化剂脱硝性能的影响.结果表明:采用不同模板剂制备得到的TiO_(2)载体,其晶型、孔结构参数和表面形貌均有变化,结合催化剂脱硝效率评价结果发现:具有混晶结构载体的样品脱硝性能最佳,而表面平滑的催化剂形貌和较高的比表面积有利于脱硝活性的提高.样品在150~400℃区间均表现出高效的NO转化性能,尤其是在低温区(100~200℃)表现出对温度的快速响应,对于燃煤电厂烟气脱硝过程具有重要的实用价值.

Selective catalytic reduction(SCR)is one of the primary methods for denitration in coal-fired power plant boilers.In this work,vanadium-tungsten-titanium(V-W-Ti,V_(2)O_(5)-WO_(3)/TiO_(2))catalyst was prepared with mesoporous TiO_(2) support.The relationship between the denitration performance of the catalyst and the crystal shape,mesoporous structure and surface morphology of TiO_(2) carrier was investigated.The results showed that the crystal shape,pore structure and surface morphology varied for TiO_(2) carriers prepared with different templates.In combination with the study on the denitration efficiency of catalysts,it was shown that the TiO_(2) carrier with a mixed crystal structure displayed the optimal denitration performance,and that TiO_(2) supports with both smooth surface and high specific surface area were beneficial to the improvement of denitration activity.Moreover,all the catalysts showed a high NO conversion efficiency in the range of 150—400℃and made a rapid response in lowtemperature region(100—200℃).These results have a significant practical value for the flue gas denitration in coal-fired power plants.