Modified nanosepiolite as an inexpensive support of tetraethylenepentamine for CO2 sorption

In this work, an inorganic-organic CO2 sorbent was prepared by immobilizing tetraethylenepentamine (TEPA) onto acid-modified nanosepiolite, a low cost and widely available clay. Nanosepiolite was pre-modified with acid treatment to enhance its surface area, increasing the surface area from 103.4 to 272.45 m(2)/g. The prepared sorbents were characterized using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, and BET (Brunauer-Emmett-Teller) analysis. At the optimal TEPA loading of 60 wt.% on the modified nanosepiolite, the CO2 sorption capacity reached 3.8 mmol CO2/g-sorbent for 1 vol.% CO2 in N-2 along with similar to 1 vol.% H2O at 60 degrees C. Studies show that the sorbent has a high CO2 adsorption rate that is beneficial to the reduction of CO2 capture capital costs. The polymer composite has the potential to be applied as a solid sorbent for capture of ultra-dilute CO2 from gas mixtures. (C) 2014 Elsevier Ltd. All rights reserved.