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.
Keywords: LSX zeolite/AC composite; alkalinity; gas adsorption; hydrothermal synthesis; wastewater treatment.