Novel Granular Biomass-Based Carbons with Excellent C2H6/CH4 Selectivity for Recovering Light Hydrocarbons from Natural Gas

作者：Dai, Qiongbin; Liang, Wanwen^*; Liu, Zewei; Xu, Feng; Xia, Qibin; Zhou, Xin; Xiao, Jing; Li, Zhong^*

来源：ACS Sustainable Chemistry & Engineering, 2022, 10(17): 5633-5642.

DOI：10.1021/acssuschemeng.2c00319

• granular carbon
• light hydrocarbons
• adsorption and separation
• selectivity

It is highly desirable to develop a binder-free preparation method to fabricate granular carbon materials with high C2H6/CH4 selectivity and C2H6 capacity for recovering light hydrocarbons from natural gas (NG). Here, we developed a facile and cost-effective method for preparing granular biomass-based carbon materials (GBCMs) without a binder. The resulting granular GBCMs were characterized, and their adsorption properties toward light hydrocarbons CH4, C2H6, and C3H8 were examined. The resulting GBCMs presented uniform particle size at macro level and were rich in microporous structures microscopically, with the Brunauer-Emmett-Teller surface area up to 939 m(2)/g. Its average crush strength reached 23.0 N/particle. The sample GBCM-900 presented excellent C2H6 adsorption capacity and selectivity. Its C2H6 uptake at 0.1 bar and 1.0 bar reached as high as 1.70 and 3.51 mmol/g. The ideal adsorbed solution theory-predicted selectivities for the equimolar C2H6/CH4 and C3H8/CH4 mixtures under the condition of 298 K and 1.0 bar were up to 23.0 and 196.0, respectively, much superior to most of powdery metal-organic frameworks and powdery carbon-based materials. The breakthrough experiment further demonstrated that GBCMs could completely separate CH4/C2H6/C3H8 ternary mixture at the ambient condition. Molecule simulation was applied to reveal the roles of the different oxygen-containing functional groups in improving C2H6/CH4 and C3H8/CH4 adsorption selectivity on GBCMs. With excellent selectivity and inherent stability, GBCMs as a granular adsorbent would be very promising for recovering light hydrocarbons from NG practically.

• 单位
  广州大学; 佛山科学技术学院