Experimental Investigation of Adsorption and CO2/CH4 Separation Properties of 13X and JLOX-500 Zeolites during the Purification of Liquefied Natural Gas

Yongbiao Sun; Jianfeng Tang; Guangyan Li; Yihuai Hua; Hui Li; Suyang Hu

doi:10.1021/acsomega.2c01211

Experimental Investigation of Adsorption and CO₂/CH₄ Separation Properties of 13X and JLOX-500 Zeolites during the Purification of Liquefied Natural Gas

ACS Omega. 2022 May 26;7(22):18542-18551. doi: 10.1021/acsomega.2c01211. eCollection 2022 Jun 7.

Authors

Yongbiao Sun^{1

2}, Jianfeng Tang¹, Guangyan Li¹, Yihuai Hua³, Hui Li¹, Suyang Hu³

Affiliations

¹ College of Pipeline and Civil Engineering, China University of Petroleum (East China), Qingdao 266580, China.
² College of Zhongran Engineering, Hebei Normal University, Shijiazhuang 050024, China.
³ CNOOC Gas & Power Group Research & Development Center, Beijing 100027, China.

Abstract

Efficient adsorbents are critical to the purification of liquefied natural gas (LNG) by the adsorption method. In this study, the physiochemical properties of JLOX-500 and 13X were examined. JLOX-500 with more Al content had a more compact unit cell, a larger surface area and pore volume, a smaller average pore size, and more microchannels on the surface than 13X. The separation performance of the two adsorbents was evaluated by the adsorption experiment. The CO₂ adsorption capacity of JLOX-500 was higher than that of 13X, while the equilibrium and ideal selectivity and separation factor of CO₂/CH₄ were also larger for JLOX-500. Especially in dynamic adsorption, the CO₂ adsorption capacities at 50 ppm of the gas mixture at the outlet were 3.46 and 1.64 mmol/g for JLOX-500 and 13X, respectively. The adsorption heats of CO₂ and CH₄ on JLOX-500 were 40.50 and 18.77 kJ/mol, whereas these values were 31.49 and 18.50 kJ/mol for 13X, respectively. A better separation performance for JLOX-500 was observed because of fewer binders and a lower Si/Al ratio (1.34). The Toth adsorption isotherm model described best the experimental data. According to the results of this study, JLOX-500 was a more efficient adsorbent used in purification for LNG production at high pressure with low CO₂ concentration.