Chitin-derived fibrous carbon microspheres as support of polyamine for remarkable CO2 capture

Abstract

Supported polyamines are promising candidates for the chemical adsorption of CO2, the performance of which is highly dependent on the porous structure of supports. In this work, we synthesized a kind of fibrous carbon microspheres (FCMs) from environmentally friendly and low-cost chitin. The synthesized FCMs have microspheric morphology and fibrous sub-architecture, and the carbon fibers interweave to form pores with large diameters. The flexibility of the pores formed by the interweaving of carbon fibers also enable the supporting of high quantity of polyamines. Given these features, pentaethylenehexamine (PEHA) was physically dispersed in the pores of FCMs to prepare PEHA/FCMs adsorbents, which were systematically characterized and investigated for CO2 capture performance. It is found that PEHA/FCMs adsorbents show excellent ability for CO2 adsorption, with the highest CO2 capacity of 3.90 mmol g−1 at 75 °C when using 10 vol% of CO2 for determinations. The reversibility of PEHA/FCMs adsorbents for CO2 adsorption is also fairly good, and PEHA/FCMs adsorbents have strong ability for the selective adsorption of low-content CO2 from N2.