Structure design of a hyperbranched polyamine adsorbent for CO 2 adsorption

• Published in: Green chemistry : an international journal and green chemistry resource : GC 2016, Vol.18 (21), p.5859-5869
• Main Authors: He, Hui, Zhuang, Linzhou, Chen, Shuixia, Liu, Hucheng, Li, Qihan
• Format: Article
• Language: English
• ISSN: 1463-9262; 1463-9270
• DOI: 10.1039/C6GC01416J

An amino-terminated hyperbranched polymer (HBP-NH 2 ) has been prepared through the Michael addition reaction between amines and methyl acrylate (MA) at 0 °C, followed by self-condensation of the addition reaction products at 100 °C and 140 °C. A novel CO 2 -“imprinted” hyperbranched polymeric adsorbent (IHBPA) with a high amino density was conveniently prepared by using glutaraldehyde to crosslink HBP-NH 2 which had pre-adsorbed CO 2 . Through comparing the adsorption capacities of the IHBPA with HBPA, which was prepared with a similar procedure to that of IHBPA but without CO 2 pre-adsorption, it could be found that the pre-adsorbed CO 2 on HBP-NH 2 would occupy the reactive sites of amino groups, and play the role of “imprinting” in the preparation of the adsorbent. The adsorption capacity of the IHBPA could thus be improved. After reducing the imino groups of the IHBPA to alkyl amine by NaBH 4 , the adsorption capacity of the reducing solid amine adsorbent (IHBPA-R) can be further improved. The prepared solid amine adsorbents also showed promising regeneration performance, which could maintain almost the same adsorption capacity for CO 2 after 10 adsorption and desorption recycles. The high CO 2 adsorption capacity (7.65 mmol g −1 ) of IHBPA-R can be attributed to its high amino density, terminal amine and hyper-branched structures.