Cotton-Based Activated Carbon Fiber with High Specific Surface Area Prepared by Low-Temperature Hydrothermal Carbonization with Urea Enhancement

The traditional preparation method of activated carbonfiber ishigh-temperature carbonization and activation. In this experiment,cotton-based activated carbon fiber was prepared by urea-enhancedlow-temperature hydrothermal carbonization and activation method.A specific surface area of 2304.8 m(2)/g of activated carbonfiber prepared by low-temperature hydrothermal carbonization withurea enhancement was the maximum reported using biomass as a raw material,which was higher than that of activated carbon fibers prepared byother biomass raw materials. X-ray photoelectron spectroscopy andelemental analysis studies have shown that the form of N transformedand decomposed during the high-temperature process, leading to theseparation of C-N. Thermogravimetry mass spectrometry characterizationanalysis found that K2CO3 of low-temperaturehydrothermal-assisted KOH activation may fully react with the N-containinggroup produced during the carbonization process to generate NH3, which lead to the formation of more pore structures in thecarbon materials. The adsorption capacity of activated carbon fiberactivated by hydrothermal-assisted KOH for iodine could reach up to2254.8 mg/g. This process provides a new idea for the preparationof high-performance activated carbon fibers.