摘要
将HZSM-5(n(SiO2)/n(Al2O3)=25,38,50和93.5),HM,Hβ,HY和γ-Al2O3等多种固体酸催化剂用于二甲醚(DME)水解,并将其分别同自制的CuO/ZnO/Al2O3催化剂进行机械混合,制备双功能催化剂并用于DME水蒸气重整制氢反应.结合NH3程序升温脱附表征手段,考察了固体酸催化剂酸性位的强度、酸量及种类对DME水解和重整反应的影响;结合热重-差热扫描量热分析表征手段,研究了HZSM-5(93.5)和γ-Al2O3在DME水解过程中的稳定性.在此基础上,进一步研究了固体酸催化剂对DME重整制氢反应中DME转化率、H2摩尔产率以及含碳气体产物选择性的影响.结果表明,固体酸催化剂的酸性位的强度和酸量对DME重整制氢过程具有显著的影响,强酸度和高酸量无益于DME水蒸气重整制氢;以HZSM-5为固体酸的双功能催化剂具有较好的低温活性,而以γ-Al2O3为固体酸的双功能催化剂在高温下具有较高的H2产率.
Dimethyl ether（DME） hydrolysis was carried out over different solid acid catalysts including HZSM-5（n（SiO2）/n（Al2O3） = 25,38,50 and 93.5）,HM,Hβ,HY,and γ-Al2O3.CuO/ZnO/Al2O3 that was prepared by the co-precipitation method and mechanically mixed with these solid acids was used for DME steam reforming（DME SR）.By NH3 temperature-programmed desorption,the influences of acid strength,acid amount,and acid site type on DME hydrolysis and DME SR were studied.The stability of the selected solid acids during DME hydrolysis was investigated by thermal gravity-differential scanning calorimetry.Furthermore,the effects of different solid acids on DME conversion,H2 production rate,and selectivity for carbonaceous products were also discussed.The results showed that the acid strength and acid amount of solid acid played a significant role on DME SR.The solid acid catalysts with high acid strength and large acid amount were not suitable for H2 production.The bi-functional catalyst composed of HZSM-5 and CuO/ZnO/Al2O3 had higher catalytic activity at low temperatures,while the bi-functional catalyst composed of γ-Al2O3 and CuO/ZnO/Al2O3 showed higher H2 production rate at high tempera-tures.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第4期297-304,共8页
基金
同济大学-壳牌公司国际合作项目(20071193)
关键词
固体酸催化剂
氧化铜
氧化锌
氧化铝
二甲醚水解
二甲醚水蒸气重整
制氢
solid acid catalyst
copper oxide
zinc oxide
alumina
dimethyl ether hydrolysis
dimethyl ether steam reforming
hydrogen production
