Synthesis and Characterization of LSX Zeolite/AC Composite from Elutrilithe

The porous carbonaceous precursor obtained from elutrilithe by adding pitch powder and solid SiO₂ was employed for the first time in an in situ hydrothermal synthesis of LSX zeolite/AC composite. The synthesized samples were characterized by XRD, SEM, and N₂ adsorption-desorption. The optimum conditions for the hydrothermal synthesis process were set as follows: gelling, aging, and crystallization. The time and temperature required for these steps were 24 h and 65 °C, 12 h and 20 °C, and 48 h and 65 °C, respectively. The molar ratios were (Na₂O + K₂O)/Al₃O₂ = 7.7, K₂O/(K₂O + Na₂O) = 3. The potential applicability test of the product showed high CO₂ working capacity, excellent CO₂/CH₄ and CO₂/N₂ selectivity, and high phenol adsorption capacity. These results suggest that the resultant product has excellent potential value in industrial application.