Composite Sorbents Based on Carbon Nanotubes and K<sub>2</sub>CO<sub>3</sub> for CO<sub>2</sub> Capture from Ambient Air
Vladimir S. Derevschikov, В. Л. Кузнецов, Janna V. Veselovskaya, С. И. Мосеенков, D. A. Yatsenko, Alexey P. Suknev, A. A. Leonova, N. V. Makolkin, Pavel S. Ruvinskiy
Abstract
K 2 CO 3 -containing sorbents supported on carbon nanotubes (CNT) were prepared via one-pot extrusion molding and heat treatment. The porous CNTs were mixed with a water-isopropyl alcohol solution of potassium acetate (CH 3 COOK) and extruded by a plunger extruder. After drying in air, extrudates were calcined at 500 °C in argon to obtain the sorbents with a K 2 CO 3 weight content in a range of 13.1–44.8 wt %. Samples were characterized using various techniques (scanning electron microscopy (SEM), X-ray diffraction (XRD), and low-temperature nitrogen adsorption) and were tested in the process of carbon dioxide capture from ambient air. The sorbent with 44.8 wt % K 2 CO 3 demonstrated the promising dynamic CO 2 -sorption capacity (up to 8.9 wt %) under temperature-swing adsorption (TSA) cycle conditions. Taking into account that the sorbents need a relatively low temperature for regeneration (150 °C) while demonstrating high CO 2 -sorption capacity in the sequence of TSA cycles, these sorbents may be of interest for direct air capture applications.