中国科学院大连化物所包信和研究小组取得一项新突破。他们的研究解决了合成气到轻质烯烃催化转化中活性和选择性的矛盾。这一研究成果发表在2023年5月19日出版的国际学术期刊《科学》上。

据了解，打破活性和选择性之间的矛盾一直是催化领域的长期挑战。课题组研究人员通过在金属氧化物沸石催化剂框架中引入锗取代AIPO-18，展示了在合成气向轻质烯烃直接转换的过程中，将目标反应从二级反应中解耦的重要性。

通过增加活性位点密度，催化活跃的Bronsted酸位点的减活使乙烯酮中间体碳碳偶联形成烯烃的目标反应得以增强，同时抑制了消耗烯烃的二级反应。这种方法可以同时获得83%的轻质烯烃选择性（在各种碳氢化合物中）和85%的CO转化率，实现了高达48%的前所未有的轻质烯烃产率，而至今报道过的产率都≤27%。

附：英文原文

Title: Disentangling the activity-selectivity trade-off in catalytic conversion of syngas to light olefins

Author: Feng Jiao, Bing Bai, Gen Li, Xiulian Pan, Yihan Ye, Shengcheng Qu, Changqi Xu, Jianping Xiao, Zhenghao Jia, Wei Liu, Tao Peng, Yilun Ding, Cheng Liu, Jinjing Li, Xinhe Bao

Issue&Volume: 2023-05-19

Abstract: Breaking the trade-off between activity and selectivity has been a long-standing challenge in the field of catalysis. We demonstrate the importance of disentangling the target reaction from the secondary reactions for the case of direct syngas conversion to light olefins by incorporating germanium-substituted AlPO-18 within the framework of the metal oxide–zeolite (OXZEO) catalyst concept. The attenuated strength of the catalytically active Brnsted acid sites allows enhancing the targeted carbon-carbon coupling of ketene intermediates to form olefins by increasing the active site density while inhibiting secondary reactions that consume the olefins. Thus, a light-olefins selectivity of 83% among hydrocarbons and carbon monoxide conversion of 85% were obtained simultaneously, leading to an unprecedented light-olefins yield of 48% versus current reported light-olefins yields of ≤27%.

DOI: adg2491

Source: https://www.science.org/doi/10.1126/science.adg2491