Porous materials have widespread industrial applications in adsorption and catalysis, but experimental studies providing atomistic data regarding gas–sorbent interactions under application-relevant conditions are limited. Current analytical methods give information about either the crystal structure or the macroscopic kinetics involved in these processes, but not their interplay. The development of a new combination of stroboscopic, isotope-contrasted neutron total scattering and steady-state isotopic transient kinetic analysis provides insight into both areas. An advanced data reduction procedure was developed to isolate the differential isotope signal from the stroboscopic neutron diffraction. These data, combined with measurement of adsorption isotherms and theoretical considerations from Grand Canonical Monte Carlo simulation, enabled the location of a heterogeneous distribution of nitrogen adsorption sites in calcium exchanged zeolite X under operational conditions (1 atm, 300 K). The nitrogen is found to adsorb primarily at Ca site II, drawing the associated Ca atoms further out into the cage structure. This approach has great potential for the investigation of gas sorption, separation, and catalysis processes in process-relevant conditions.

中文翻译：

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用频闪光谱同位素对比中子总散射捕获沸石X中N ₂吸附的细节

多孔材料在吸附和催化方面具有广泛的工业应用，但是提供与应用相关条件下气体-吸附剂相互作用的原子数据的实验研究有限。当前的分析方法提供有关这些过程中涉及的晶体结构或宏观动力学的信息，但不提供它们之间的相互作用。频闪，同位素对比中子总散射和稳态同位素瞬态动力学分析的新组合的开发提供了对这两个领域的洞察力。开发了一种先进的数据缩减程序，以从频闪中子衍射中分离出差分同位素信号。这些数据，结合吸附等温线的测量以及来自Grand Canonical Monte Carlo模拟的理论考虑，能够在操作条件下（1个大气压，300 K）在钙交换沸石X中定位氮吸附位点的非均质分布。发现氮主要吸附在Ca位置II，将相关的Ca原子进一步拉出进入笼状结构。这种方法对于研究过程相关条件下的气体吸附，分离和催化过程具有巨大的潜力。