Effect of 1,3-Dioxolane on Gas Separation Kinetics via Gas Hydrates
Xing-Ya Ni, Xiaofang Lv, Rongqiang Zhong, Yang Liu, Chuanshuo Wang, Qianli Ma, Yan-Yun Xiao, Shidong Zhou, Shangfei Song
Abstract
The mixed gas separation of hydrate technology can promote biogas separation, purify CO 2, and improve the quality of CH 4 while reducing carbon emissions and realizing efficient CO 2 capture and storage. Herein, we identified the effects of low-content 1,3-dioxolane (DIOX) on the separation efficiency and kinetics of a CH 4 /CO 2 (6:4) mixture via gas hydrates. The experimental results showed that the hydrate formation with DIOX had five stages. The purification rate of CH 4 could be effectively accelerated with the increase in DIOX concentrations. At 4.5 MPa and 274.65 K, the induction time of hydrate formation could be reduced by 93.3% compared to that of the pure water system. However, higher driving forces could lead to dense hydrate film and reduce the separation efficiency of CO 2 /CH 4 . The suitable pressure and temperature (e.g., 4 MPa, 274.65 K) could alleviate this problem, and it could result in a CO 2 recovery of 92.2%. When the gas–liquid ratio was 3.5, the CO 2 recovery could be increased by 23% and the CO 2 phase equilibrium constant could be increased by 2.8 times compared to that of the pure water system.