【摘要】：氮氧化物(NOx)是全球大氣污染主要污染物之一,以NH3作為還原劑的選擇性催化還原技術(shù),即NH3-SCR技術(shù)是目前應用最為廣泛的氮氧化物脫除技術(shù)。本論文以分析純偏釩酸銨、銳鈦礦型鈦白粉為主要原料,制備了三葉草形條狀催化劑顆粒,通過改變焙燒溫度,來考察其對于成型催化劑脫硝活性以及抗壓機械強度的影響。結(jié)果表明,當焙燒溫度為450℃時,催化劑樣品具有最佳的脫硝催化活性以及抗壓機械強度。通過DRIFTS研究了催化反應機理。結(jié)果表明,在低溫條件下,NH3在催化劑表面主要吸附在在B酸位上和L酸位上;NO+O2的吸附分為雙齒硝酸鹽、(N2O2)2-、單齒硝酸鹽、橋式硝基-亞硝酸鹽物種以及表面吸附的N02等形式,但是相對于NH3的吸附來說,NO+02的吸附量是較少的;氣相或弱吸附的NO2是NO主要反應的途徑,Br(?)nsted酸位相對于Lewis酸位來說更容易參加反應,低溫下的反應主要遵從L-H機理。通過改變催化劑制備過程中的干燥溫度以及干燥時間來研究其對于催成型催化劑活性及抗壓機械強度的影響,通過優(yōu)化催化劑成型配方,找出最佳的H3BO3+SiO2添加量,并測試了最佳條件下的催化劑樣品的抗水抗硫性。結(jié)果表明,在干燥溫度為80℃,干燥時間為0.5 h時,催化劑樣品具有最佳的脫硝催化活性以及抗壓機械強度;添加H3BO3+SiO2量為7.5 %時,催化劑抗壓機械強度提高最為明顯,且穩(wěn)定性較好。
[Abstract]:Nitrogen oxide (NOx) is one of the major pollutants in global air pollution. The selective catalytic reduction technology with NH3 as reducing agent, that is, NH3-SCR technology, is the most widely used nitrogen oxide removal technology at present. In this paper, the pure ammonium metavanadate and anatase titanium dioxide were used as the main raw materials to prepare the clover bar catalyst particles. By changing the calcination temperature, the effects of the catalyst on denitrification activity and compressive mechanical strength were investigated. The results show that the catalyst has the best denitrification activity and compressive mechanical strength when the calcination temperature is 450 鈩，

本文編號：2370808