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Lithium‐based zeolites are the most commonly used materials in PSA (pressure swing adsorption) oxygen concentration from atmospheric air. Synthesizing these adsorbents using mineral raw materials adapts to worldwide environmental requests, as only high‐purity chemical reactants such as aluminates and silicates are usually used. The present work aims to synthesize and characterize zeolites using kaolin as raw material by studying the influence of the metakaolinization temperature and SiO2/Al2O3 and H2O/Na2O molar ratios by experimental design. Ion exchange was used to incorporate lithium into synthesized zeolites. Kaolin was treated thermically and characterized, and zeolites were synthesized by a hydrothermal reaction. After synthesis, ionic exchange of Na+ ions by Li+ was performed. The results indicated the presence of three main phases, zeolites A, X, and P. Using ANOVA, it was found that the factors that contributed significantly to the formation of zeolite X were the H2O/Na2O and SiO2/Al2O3 molar ratios. For zeolite A, the major influence was by the metakaolinization temperature and for zeolite P none of the factors was influential. Zeolites that incorporated higher amounts of lithium showed higher N2 adsorption potential, indicating that even without pure phases formed, it was possible to obtain similar adsorption efficiency to commercial zeolite.

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