摘要
CO2加氢被认为是目前固定大量排放CO2的最好方法之一.研发出一种碳纳米管(CNT)促进的Cu-ZrO2-HZSM-5沸石分子筛双功能混合型催化剂,将其用于CO2加氢合成甲醇和甲醇脱水生成二甲醚(DME)二步串联催化一器化,实现由(CO2+H2)直接合成DME.在5.0 MPa,523 K,V(H2)∶V(CO2)∶V(N2)=69∶23∶8,空速(GHSV)=25 000mL/(h.g)的反应条件下,在所研发(Cu2Zr3-10%CNT)-30%HZSM-5催化剂上,CO2加氢的转化率达9.44%,比相应单功能加氢催化剂(Cu2Zr3-10%CNT)的相应值(7.00%)提高35%.CNT能作为Cu-ZrO2-HZSM-5双功能混合型催化剂的促进剂.在上述反应条件下,含CNT的催化剂的DME时空产率达438mg/(h.g),比不含CNT的原双功能混合型基质催化剂的相应值(395mg/(h.g))提高11%.结果证实,利用双功能混合型催化剂,将CO2加氢合成甲醇和甲醇脱水生成DME两个过程串联催化一器化,能大幅度提高CO2加氢转化的效率.
In order to improve the climate conditions,it is desirable to develop methods to convert CO2 into valuable chemicals. Here we report the development of a CNT-promoted Cu-ZrO2-HZSM-5 bi-functional hybrid catalyst, which was used for the ＂one pot＂ two-step catalytic synthesis of DME from （CO2 ＋ He ） via CH：~ OH. Over the developed catalyst of （Cu2 Zra-10 ~CNT） 30 ~ HZSM-5 under the reaction conditions of 5.0 MPa,523 K,V（H2）：V（CO2）：V（Ne）=69：23=8,GHSV=25 000 mL/（h.g）,the CO2 hydrogen ation conversion reached 9.44 %. This value was 1.35 times that （7.00 %） of the mono-functional hydrogenation catalyst of Cu2 Zra 10%CNT. The CNT could act as a novel promoter of the Cu-ZrO2-HZSM-5 bi-functional hybrid catalyst. Under the aforementioned reaction conditions,the space-time-yield （STY） of DME reached 438 mg/（h. g） over the CNT-containing bi-functional hybrid cata lyst,which was 1.11 times that （395 mg/（h.g）） of the corresponding CNT-free counterpart. The results of the present work demon- strated that combination of the process for methanol synthesis with that for methanol dehydration to produce DME by using bi-func tional hybrid catalyst could markedly improve the efficiency of CO2 hydrogenation-conversion.
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
2012年第6期1036-1042,共7页
Journal of Xiamen University：Natural Science
基金
国家重点基础研究发展计划(973)项目(2011CBA0050-8)
优秀国家重点实验室研究项目基金(20923004)
教育部创新团队项目(IRT1036)
福建省重大专项专题项目(2009HZ0002-1)
