Abstract:

By taking the advantages of easy decomposition and catalytic function of basic magnesium carbonate, the mechanically stable porous carbon materials (MCM-Mg) are synthesized through rapid gelation of resorcinol with formaldehyde and subsequently carbonization. Compared with samples catalyzed by traditional carbonates, the synthesis process can obtain a well-developed porous structure. The resulted samples can withstand a pressure of up to 9.4 MPa. At 273 K, the equilibrium CO₂ adsorption capacities of MCM-Mg are in the range of 3.49—4.50 mmol·g^-1 at 0.1 MPa and can reach 1.87 mmol·g^-1 at 0.015 MPa. Experimental test of the MCM-Mg shows that the micropores play a major role in contribution of the amount of adsorbed CO₂. Importantly, MCM-Mg can adsorb 7.15 μmol CO₂ per S_micro, which surpasses most of the carbons prepared by activation. Dynamic breakthrough tests show that over such series of samples, CO₂/N₂ streams can be fully separated. The CO₂ release is achieved facilely in Ar purge at 298 K. The samples also exhibit stable performance for CO₂ separation under humid conditions and exhibit good regeneration capability.

Key words: porous carbon, CO₂ capture, basic magnesium carbonate, adsorption, porous media, dynamic breakthrough

摘要：

利用碱式碳酸镁的催化功能及易分解特性,实现间苯二酚、甲醛的快速凝胶,炭化得到孔隙发达的整体式多孔炭(MCM-Mg),其轴向抗压强度达9.4 MPa。与普通碳酸盐催化的样品相比,MCM-Mg孔隙更为发达。273 K下该系列样品的静态CO₂吸附量可达3.49~4.50 mmol·g^-1 (0.1 MPa),0.015 MPa最高可达1.87 mmol·g^-1。研究发现,微孔对材料吸附性能起主导作用;MCM-Mg的单位微孔比表面积可吸附7.15 μmol CO₂,超过了大部分活化法制备的炭材料。多组分动态穿透实验表明,该系列材料可实现CO₂/N₂的完全分离;材料具有良好的耐水汽性能和循环吸附-脱附性能,室温下经惰性气体吹扫即可实现再生。

关键词: 多孔炭, 二氧化碳捕集, 碱式碳酸镁, 吸附, 多孔介质, 动态穿透