Abstract: In order to meet the emission standard of nitrogen oxides (NO_x) in the flue gas of batch furnaces through dry adsorption,calcia silica inorganic adsorbents were prepared with limestone and quartz as raw materials.Sample Cu-BTC 1^# was obtained by solvothermal synthesis,drying and purification in vacuum at 120 using trimesic acid (H₃BTC) and copper nitrate trihydrate (Cu(NO₃)₂·3H₂O) as raw materials; likewise,sample Cu-BTC 3^# was obtained at 200 ℃.Sample Cu-BTC 2^# was obtained by hydrothermal synthesis,drying and purification in air (metal organic skeleton MOFs materials,1,3,5-benzenetricarboxylic acid copper).The two types of materials were tested in terms of the NO₂ adsorption,and then the specific surface area,the pore volume,the NO₂ adsorption performance,the phase composition,the microstructure,and the thermal stability of adsorbent materials were explored via N₂ physical adsorption-desorption,SEM,XRD and TG characterization.The results show:(1)the Cu-BTC samples have higher adsorption capacity than the calcia silica adsorbent,in which sample Cu-BTC 3^# has the largest specific surface area and pore volume,thus adsorption capacity for NO₂;(2)the calcia silica adsorbent has better thermal stability and lower total mass loss during the entire process than the Cu-BTC samples;sample Cu-BTC 2^# has better thermal stability than the other two Cu-BTC samples,and the metal Cu active sites of the Cu-BTC samples can be exposed at least above 150 ℃.

Key words: nitrogen oxides (NO_x), Cu-BTC, calcia silica inorganic adsorbent, adsorption capacity, specific surface area, thermal stability

摘要： 为实现间歇式窑炉烟气中氮氧化物(NO_x)通过干法吸附达标排放,以石灰石和石英为原料制备了钙硅质无机吸附剂;以均苯三甲酸(H₃BTC)和三水合硝酸铜(Cu(NO₃)₂·3H₂O)为原料,采用溶剂热法合成并分别在120、200 ℃真空中干燥纯化得到1^#Cu-BTC和3^#Cu-BTC试样,采用水热法合成并在空气中干燥纯化得到2^#Cu-BTC试样(金属有机骨架MOFs材料1,3,5-均苯三羧酸铜)。然后对两类材料进行了NO₂吸附测试,通过N₂物理吸附-脱附、SEM、XRD和热重分析探究了吸附材料的比表面积和孔体积大小、NO₂的吸附性能、物相组成、显微结构和热稳定性。结果表明:1)Cu-BTC试样比钙硅质吸附剂吸附容量大,其中溶剂热法合成、在200 ℃真空中干燥纯化得到的3^#Cu-BTC试样比表面积和孔体积最大,对NO₂的吸附容量也最大,钙硅质材料的吸附容量较小。2)钙硅质吸附剂的热稳定性优于Cu-BTC试样的,整个过程的质量总损失低于Cu-BTC试样的。2^#Cu-BTC试样的热稳定性优于其他两种Cu-BTC试样的,Cu-BTC试样至少在150 ℃以上金属Cu的活性位点才可以暴露出来。

关键词: 氮氧化物(NO_x), Cu-BTC, 钙硅质无机吸附剂, 吸附容量, 比表面积, 热稳定性