CAJ | 학술논문

以拟薄水铝石、硝酸镍以及镁、钴、镧和铁的硝酸盐为原料,尿素为燃烧剂,采用尿素燃烧法制备系列镍基(以及含助剂)甲烷化催化剂.通过XRD和BET等对催化剂结构进行表征,采用固定床反应器评价催化剂的合成气甲烷化催化反应性能,考察Ni含量、尿素与原料质量比、焙烧温度和不同助剂等对催化剂结构和性能的影响,评价催化剂的稳定性.结果表明,NiO 质量分数为7. 5% ~44. 8%时,采用尿素燃烧法均可制备γ-Al2O3 为载体的镍基甲烷化催化剂,最佳制备条件为:尿素与原料质量比3:1 ,焙烧温度450 ℃,燃烧时间40 min.26 . 1%NiO/γ-Al2O3 催化剂表现出较好的催化性能,在230 ℃和常压条件下,CO转化率和CH4 选择性分别达99 . 5%和98 . 3%.26. 1%NiO-2. 6%La2O3/γ-Al2O3 催化剂在(230~700)℃经过多次升降反应温度和1 460 h的长周期稳定性测试,表现出较好的稳定性和耐热冲击性能.
이의박수려석、초산얼이급미、고、란화철적초산염위원료,뇨소위연소제,채용뇨소연소법제비계렬얼기(이급함조제)갑완화최화제.통과XRD화BET등대최화제결구진행표정,채용고정상반응기평개최화제적합성기갑완화최화반응성능,고찰Ni함량、뇨소여원료질량비、배소온도화불동조제등대최화제결구화성능적영향,평개최화제적은정성.결과표명,NiO 질량분수위7. 5% ~44. 8%시,채용뇨소연소법균가제비γ-Al2O3 위재체적얼기갑완화최화제,최가제비조건위:뇨소여원료질량비3:1 ,배소온도450 ℃,연소시간40 min.26 . 1%NiO/γ-Al2O3 최화제표현출교호적최화성능,재230 ℃화상압조건하,CO전화솔화CH4 선택성분별체99 . 5%화98 . 3%.26. 1%NiO-2. 6%La2O3/γ-Al2O3 최화제재(230~700)℃경과다차승강반응온도화1 460 h적장주기은정성측시,표현출교호적은정성화내열충격성능.
Using pseudo-boehmite as aluminum source,nickel nitrate as nickel source,magnesium nitrate,cobalt nitrate,lanthanum nitrate and ferric nitrate as the promoter source,a series of Ni-based methanation catalysts with the promoters was prepared by urea combustion method. The structure of the catalysts was characterized by XRD and BET. The performance of the catalysts for syngas methanation was evaluated in a fixed bed reactor. The effects of NiO contents,mass ratios of urea and raw material,calcina-tion temperatures and the promoters on the structure and performance of the catalysts were investigated. The results indicated that the syngas methanation catalysts with NiO mass fraction of 7 . 5% -44 . 8% andγ-Al2O3 support were prepared by urea combustion method. The optimal preparation condition was as follows:massratioofureatorawmaterialnitrate3:1,calcinationtemperature450℃andcalcinationtime 40 min. Among all the catalysts,26. 1%NiO/γ-Al2O3 catalyst exhibited the excellent performance for syngas methanation reaction. Under the condition of reaction temperature 230 ℃ and atmospheric pres-sure,the conversion of CO and the selectivity to CH4 reached 99. 5% and 98. 3%,respectively. 26. 1%NiO-2. 6%La2O3/γ-Al2O3 catalyst possessed good stability and heat shock resistance during 1 460 h stablity test after the reaction temperature was increased and then decreased many times in the range of (230-700)℃.