High-Throughput Computational Study On Host-Guest Interactions During Zeolite Synthesis And Adsorption Processes

Owing to the unique topology system,the good thermal stability,tunable composition,and high surface area,zeolites have been widely used in many important physical and chemical processes,including adsorption,separation,and shape-selective catalysis.The host-guest interaction between zeolite and the guest molecules in the pores is the basis for understanding the processes of zeolite synthesis,adsorption,separation,and catalysis.Facing different zeolite frameworks such as pure silica,SAPO,AlPO,etc.,we perform a high-throughput calculation including the host-guest interactions of zeolite and organic molecules and small gas molecules as adsorbates during the adsorption and separation properties.Focusing on the host-guest interactions in zeolite synthesis and adsorption,the main results are summarized as follows:(1)For the synthesis of pure silica zeolite,we report a molecular simulation study in the host-guest interactions between two silica zeolites frameworks(STW and MTW)and several common organic cations.During the study in the host-guest interactions between STW and 21 alkylated imidazolium and pyrazolium cations,we find that all successful OSDAs possess relatively more negative atomic charges on nitrogen atoms and smaller dipole moments.According to this finding,we have designed seven new alkylated imidazolium and pyrazolium cations that may be suitable for zeolite STW,and verified their structure-directing capability by molecular simulation calculations.Similarly,we simulate the host-guest interactions between MTW zeolite and 5 organic cations,find that tetraethylammonium cation is the most suitable OSDA candidate for MTW synthesis.Besides,we have designed four new cations that may be suitable for zeolite MTW.By estimating the structure-directing capability of candidate organic cations,we are able to identify the most promising OSDAs toward the rational synthesis of specific zeolite frameworks.(2)For the synthesis and acidity properties of silicoaluminophosphate zeolites,we report a high-throughput molecular simulation study in the host-guest interactions between two silicoaluminophosphate zeolites frameworks(SAPO-34 and SAPO-35)with different silicon contents and several OSDAs.During the calculation of SAPO-34 zeolite,2217 framework models are enumerated in different silicon content ranges.For SAPO-35 zeolite,88012 framework models are enumerated.On this basis,a high-throughput calculation of the host-guest interaction between these SAPO structures and OSDAs are simulated to explore the effect of OSDAs on the SAPO structures.(3)To facilitate the experimental discovery of high-performance aluminosilicate zeolites for CO2 capture,we report a high-throughput computational study on 262500 aluminosilicate zeolites to get comprehensive information about their true CO2 capture performance using binary-component simulations.We perform GCMC simulations on 2625 structures with the lowest lattice energies using a binary N2/CO2 mixture model under three industrial processing conditions.To get a comprehensive overview of the CO2 capture performance of these models,we introduce four metrics to evaluate the capture performance of these structures.Finally,we identify hundreds of hypothetical aluminosilicate zeolite structures that exhibit promising CO2 capture capability even superior to zeolite Na-X,the most efficient zeolite for CO2 capture known so far.Our results will provide important guidance toward experimental discovery of high-performance zeolites for practical CO2 capture.(4)To study the ethane/ethylene separation capability of silica zeolites,we report a systematic computational study on 236 IZA known and 375 ABC-6 hypothetical 8-ring zeolites.We perform GCMC simulations on silica zeolite structures using ethane/ethylene mixture with a molar ratio of 10/90.Similarly,we introduce four comprehensive adsorbent evaluation metrics including ethane adsorption selectivity,ethane working capacity,adsorbent performance score,and percent regenerability to evaluate the ethane/ethylene separation performance of silica zeolites.Finally,we identify ten silica zeolite structures that exhibit promising ethane capture capability.(5)For the thermal energy storage application of the water capture properties of zeolites,we conduct a high-throughput simulation study on 79 known aluminophosphates zeolites and 84292 hypothetical aluminophosphates zeolites to get the thermal energy storage capability.Finally,we predict ten aluminophosphates zeolites that exhibit promising thermal energy storage capability even superior to zeolite CHA,the commercial zeolite material.