Sustainable carbon microtube derived from cotton waste for environmental applications

© 2018 Elsevier B.V. Given its natural state and cost-effectiveness, cotton can be an ideal material for the fabrication of high performance catalyst and pollutant removal from the environment. In this study, novel carbon microtube derived from cotton waste were successfully prepared by thermal treatment of cotton in an argon atmosphere and used as a tannic acid sorbent. Carbon microtube (CMT) properties were investigated by electron microscopy (SEM, TEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), zeta potentiometer and N2 adsorption − desorption. The most stable solutions in water were established using CMT treated at 900 and 1300 °C and in tannic acid (TA) at 1100 and 1300 °C, respectively. Maximum TA sorption capacity, 596.5 mg g−1, was found for CMT treated at 1100 °C. The suitability of Langmuir model with simultaneously good fitting of other tested models of sorption implied that monolayer sorption was the first step of TA sorption onto CMT via π–π interactions and hydrogen bonds. Given the repeatability, high removal performance and cost effectiveness of the cotton based carbon microtubes when compared to other well-known sorbent such as carbon nanotubes, the carbon microtubes demonstrated great potential as low-cost and effective tannic acid (and dissolved organic matter) adsorbent.