昆明理工大学学报(自然科学版)
昆明理工大學學報(自然科學版)
곤명리공대학학보(자연과학판)
JOURNAL OF KUNMING UNIVERSITY OF SCIENCE AND TECHNOLOGY(SCIENCE AND TECHNOLOGY)
2014年
6期
110-115
,共6页
张秋林%张金辉%宁平%宋忠贤%王燕彩%徐利斯%唐小苏
張鞦林%張金輝%寧平%宋忠賢%王燕綵%徐利斯%唐小囌
장추림%장금휘%저평%송충현%왕연채%서리사%당소소
SO2-4%NH3 -SCR%脱硝%酸性位点
SO2-4%NH3 -SCR%脫硝%痠性位點
SO2-4%NH3 -SCR%탈초%산성위점
SO2-4%NH3 -SCR%denitrification%acidity site
采用共沉淀法制备了几种不同的金属氧化物催化剂(Ce-Pr-Ox、Ce-Y-Ox、Ti -Pr-Ox、Ti-Y-Ox、Ti-Al-Ox),并对其进行了硫酸盐改性.实验同时考察了SO2-4改性对催化剂氨选择性催化还原(NH3-SCR)活性和催化剂结构组成的影响.经SO2-4改性的催化剂,NOx 转化率在低温和高温均有显著提高,其中,活性最好的Ce-Pr-Ox在350~500℃范围内转化率接近100%.XRD、IR分析结果表明,催化剂经硫酸盐改性后,催化剂出现了结晶态硫酸盐;催化剂中存在M-SO2-4(M=Al,Pr和Y)键,表明了金属氧化物与硫酸盐发生了相互作用.而经SO2-4改性后催化剂优越的SCR脱硝性能与催化剂酸性位点增加密切相关.
採用共沉澱法製備瞭幾種不同的金屬氧化物催化劑(Ce-Pr-Ox、Ce-Y-Ox、Ti -Pr-Ox、Ti-Y-Ox、Ti-Al-Ox),併對其進行瞭硫痠鹽改性.實驗同時攷察瞭SO2-4改性對催化劑氨選擇性催化還原(NH3-SCR)活性和催化劑結構組成的影響.經SO2-4改性的催化劑,NOx 轉化率在低溫和高溫均有顯著提高,其中,活性最好的Ce-Pr-Ox在350~500℃範圍內轉化率接近100%.XRD、IR分析結果錶明,催化劑經硫痠鹽改性後,催化劑齣現瞭結晶態硫痠鹽;催化劑中存在M-SO2-4(M=Al,Pr和Y)鍵,錶明瞭金屬氧化物與硫痠鹽髮生瞭相互作用.而經SO2-4改性後催化劑優越的SCR脫硝性能與催化劑痠性位點增加密切相關.
채용공침정법제비료궤충불동적금속양화물최화제(Ce-Pr-Ox、Ce-Y-Ox、Ti -Pr-Ox、Ti-Y-Ox、Ti-Al-Ox),병대기진행료류산염개성.실험동시고찰료SO2-4개성대최화제안선택성최화환원(NH3-SCR)활성화최화제결구조성적영향.경SO2-4개성적최화제,NOx 전화솔재저온화고온균유현저제고,기중,활성최호적Ce-Pr-Ox재350~500℃범위내전화솔접근100%.XRD、IR분석결과표명,최화제경류산염개성후,최화제출현료결정태류산염;최화제중존재M-SO2-4(M=Al,Pr화Y)건,표명료금속양화물여류산염발생료상호작용.이경SO2-4개성후최화제우월적SCR탈초성능여최화제산성위점증가밀절상관.
A series of metal oxide catalysts (Ce-Pr-Ox,Ce-Y-Ox,Ti-Pr-Ox,Ti-Y-Ox,Ti-Al-Ox)are prepared by co-precipitation method and modified by SO2-4 for selective catalytic reduction of NOx with NH3 .The influences of SO2-4 modification on NH3 -SCR activity and structures on Ce and Ti-based catalysts are investigated.It is implied by the results that the catalytic performance of catalysts modified by SO2-4 is signifi-cantly enhanced at both low and high temperatures.Furthermore,nearly 100%NOx conversion over the Ce-Pr-Ox catalyst could be obtained throughout the temperature window of 350—500 ℃,which exhibits the highest level of NH3 -SCR activity.It is also inferred from the XRD analysis that the crystalline sulfate species are de-tected for the SO2-4 modified catalysts.Besides,the existence of sulfate species (M-SO2-4 :M=Al,Pr and Y) is found on the SO2-4 modified catalysts by the analysis of XRD and IR.Thus,it could be concluded that there exists interaction among SO2-4 and other metal.The superior SCR activity might be attributed to the increase a-mount of acid cites over the SO2-4 modified catalysts.