Chemical Engineering Department, New Mexico State University, Las Cruces, NM 88003, USA.
J Colloid Interface Sci. 2013 Mar 15;394:445-50. doi: 10.1016/j.jcis.2012.12.025. Epub 2012 Dec 19.
Adsorptive separations of C(2)H(6)/CH(4) and CH(4)/N(2) binary mixtures are of paramount importance from the energy and environmental points of view. A mesoporous carbon adsorbent was synthesized using a soft template method and characterized with TEM, TGA, and nitrogen adsorption/desorption. Adsorption equilibrium and kinetics of C(2)H(6), CH(4), and N(2) on the mesoporous carbon adsorbent were determined at 278, 298, and 318 K and pressures up to 100 kPa. The adsorption capacities of C(2)H(6) and CH(4) on the mesoporous carbon adsorbent at 298 K and 100 kPa are 2.20 mmol/g and 1.05 mmol/g, respectively. Both are significantly higher than those of many adsorbents including pillared clays and ETS-10 at a similar condition. The equilibrium selectivities of C(2)H(6)/CH(4) and CH(4)/N(2) at 298 K are 19.6 and 5.8, respectively. It was observed that the adsorption of C(2)H(6), CH(4), and N(2) gases on the carbon adsorbent was reversible with modest isosteric heats of adsorption, which implies that this carbon adsorbent can be easily regenerated in a cyclic adsorption process. These results suggest that the mesoporous carbon studied in this work is a promising alternative adsorbent for the separations of C(2)H(6)/CH(4) and CH(4)/N(2) gas mixtures.
从能源和环境的角度来看，C(2)H(6)/CH(4)和 CH(4)/N(2)二元混合物的吸附分离至关重要。采用软模板法合成了一种介孔碳吸附剂，并采用 TEM、TGA 和氮气吸附/脱附对其进行了表征。在 278、298 和 318 K 及高达 100 kPa 的压力下，测定了 C(2)H(6)、CH(4)和 N(2)在介孔碳吸附剂上的吸附平衡和动力学。在 298 K 和 100 kPa 下，介孔碳吸附剂对 C(2)H(6)和 CH(4)的吸附容量分别为 2.20 mmol/g 和 1.05 mmol/g，均显著高于类似条件下许多吸附剂（包括柱撑粘土和 ETS-10）的吸附容量。在 298 K 时，C(2)H(6)/CH(4)和 CH(4)/N(2)的平衡选择性分别为 19.6 和 5.8。结果表明，C(2)H(6)、CH(4)和 N(2)气体在碳吸附剂上的吸附是可逆的，吸附热适中，这意味着该碳吸附剂可在循环吸附过程中很容易地再生。这些结果表明，本文研究的介孔碳是 C(2)H(6)/CH(4)和 CH(4)/N(2)气体混合物分离的一种很有前途的替代吸附剂。
