Centre for Surface Chemistry and Catalysis, Katholieke Universiteit Leuven, Arenbergpark 23, B-3001 Leuven, Belgium.
J Am Chem Soc. 2013 Jul 3;135(26):9849-56. doi: 10.1021/ja403571z. Epub 2013 Jun 20.
The influence of the metal ion in the mesoporous metal trimesate MIL-100(Al(3+), Cr(3+), Fe(3+), V(3+)) on the adsorptive removal of N/S-heterocyclic molecules from fuels has been investigated by combining isotherms for adsorption from a model fuel solution with microcalorimetric and IR spectroscopic characterizations. The results show a clear influence of the different metals (Al, Fe, Cr, V) on the affinity for the heterocyclic compounds, on the integral adsorption enthalpies, and on the uptake capacities. Among several factors, the availability of coordinatively unsaturated sites and the presence of basic sites next to the coordinative vacancies are important factors contributing to the observed affinity differences for N-heterocyclic compounds. These trends were deduced from IR spectroscopic observation of adsorbed indole molecules, which can be chemisorbed coordinatively or by formation of hydrogen bonded species. On the basis of our results we are able to propose an optimized adsorbent for the deep and selective removal of nitrogen contaminants out of fuel feeds, namely MIL-100(V).
通过将模型燃料溶液中的吸附等温线与微量热法和红外光谱表征相结合，研究了介孔金属均苯三甲酸 MIL-100(Al(3+)、Cr(3+)、Fe(3+)、V(3+))中的金属离子对燃料中 N/S-杂环分子的吸附去除的影响。结果表明，不同金属（Al、Fe、Cr、V）对杂环化合物的亲和力、积分吸附焓和吸附容量有明显的影响。在几个因素中，配位不饱和位点的可用性和配位空位旁边存在碱性位点是导致观察到的 N-杂环化合物亲和力差异的重要因素。这些趋势是从吸附吲哚分子的红外光谱观察中推断出来的，吲哚分子可以通过配位或氢键形成物种进行化学吸附。基于我们的结果，我们能够提出一种优化的吸附剂，用于从燃料进料中深度和选择性地去除氮污染物，即 MIL-100(V)。
