LiLSX制氧分子筛及其金属离子交换改性的研究现状

Research Status of LiLSX Oxygen Production Molecular Sieve and its Metal Ion Exchange Modification

LiLSX制氧分子筛是当前公认的性能最好的变压吸附(PSA)分离空气制氧分子筛材料。随着锂离子电池在电动汽车及储能领域的大规模应用,与锂元素相关的化工产品的价格快速飙升,LiLSX分子筛材料也变得十分昂贵,这就促使人们开始探索提升PSA制氧用分子筛的性能以及降低成本的方法。在LiLSX分子筛的晶胞中,N_(2)(和O_(2))只能与位置3(SIII/SIII’)处的阳离子相互作用,而与其他位置上的金属离子很难发生吸附作用。基于此,研究者对LiLSX分子筛进行改性,用其他离子取代位置1(SI/SI’)和位置2(SII/SII’)的锂离子,以降低锂离子的含量,并制备了大量改性分子筛材料。但从综合成本和性能看,目前仍未能研发出性能优于LiLSX的制氧分子筛材料。

LiLSX oxygen production molecular sieve was currently recognized as the best performing pressure swing adsorption(PSA)material for separating air for oxygen production.Due to the large-scale application of lithium-ion batteries in the fields of electric vehicles and energy storage,the prices of lithium-related chemical products had rapidly skyrocketed,and LiLSX molecular sieve materials had become very expensive.This was prompted people to continue exploring ways to improve the performance of molecular sieves for PSA oxygen production and reduce costs.In the cell of LiLSX molecular sieve,N_(2)(and O_(2))molecules could only interact with cations at position 3(SIII/III‘),while adsorption with metal ions at other positions was difficult.Based on this discovery,researchers were tried to modify LiLSX molecular sieve by replacing the metal lithium ions at positions 1(SI/SI‘)and 2(SII/SII’)with other ions,in order to reduce the content of metal lithium ions and prepare a large number of modified molecular sieve materials.However,based on the overall cost and performance,a better oxygen production molecular sieve material than LiLSX was still not been developed.