Casavola Marianna, Xie Jingxiu, Meeldijk Johannes D, Krans Nynke A, Goryachev Andrey, Hofmann Jan P, Dugulan A Iulian, de Jong Krijn P
Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
Laboratory of Inorganic Materials Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Postbox 513, 5600 MB Eindhoven, The Netherlands.
ACS Catal. 2017 Aug 4;7(8):5121-5128. doi: 10.1021/acscatal.7b00847. Epub 2017 Jun 19.
Colloidal synthesis routes have been recently used to fabricate heterogeneous catalysts with more controllable and homogeneous properties. Herein a method was developed to modify the surface composition of colloidal nanocrystal catalysts and to purposely introduce specific atoms via ligands and change the catalyst reactivity. Organic ligands adsorbed on the surface of iron oxide catalysts were exchanged with inorganic species such as NaS, not only to provide an active surface but also to introduce controlled amounts of Na and S acting as promoters for the catalytic process. The catalyst composition was optimized for the Fischer-Tropsch direct conversion of synthesis gas into lower olefins. At industrially relevant conditions, these nanocrystal-based catalysts with controlled composition were more active, selective, and stable than catalysts with similar composition but synthesized using conventional methods, possibly due to their homogeneity of properties and synergic interaction of iron and promoters.
胶体合成路线最近已被用于制备具有更可控和均匀性质的多相催化剂。在此，开发了一种方法来修饰胶体纳米晶体催化剂的表面组成，并通过配体有意引入特定原子，从而改变催化剂的反应活性。吸附在氧化铁催化剂表面的有机配体与诸如NaS等无机物种进行交换，不仅是为了提供活性表面，而且是为了引入可控量的Na和S作为催化过程的促进剂。对催化剂组成进行了优化，以实现合成气直接费托转化为低级烯烃。在工业相关条件下，这些组成可控的基于纳米晶体的催化剂比具有相似组成但采用传统方法合成的催化剂更具活性、选择性和稳定性，这可能归因于它们性质的均匀性以及铁与促进剂之间的协同相互作用。
