Investigation of 4A zeolite-based natural gas dryers and their role in CO2 capture: An in-situ study

In the natural gas liquefaction process, CO2 is an undesirable component requiring removal. This study evaluated molecular sieves used to dry natural gas for CO2 retention. The sieve was characterized by XRF, XRD, FTIR, TG/DTG, BET, and SEM, confirming its zeolitic nature with Si/Al ratio of 2. Two parameters were examined: dryer progress and process pressure. The average CO2 retention at 40 bars was 2.22 ppm, while retention at 70 bars increased by 53.15 %. Competitive adsorption CO2/H2O in the 4A zeolite involved interactions such as CO2–O-framework, CO2–Na, CO2–CO2, H2O–O-framework, H2O–Na, and H2O–H2O.