Adsorption properties of activated carbon from reed with a high adsorption capacity

•Activated carbon was prepared using reed from Yellow River Delta of China as a low-cost raw material.•The maximum adsorption capacity of the prepared activated carbon for MB can get to 704.23 mg/g.•The experimental data were analyzed using different adsorption models, which is well fitting with the Langmuir isotherm model and pseudo second-order kinetics.•The reed activated carbon had better regeneration performance.

Activated carbon with a high adsorption capacity was prepared using reed from the Yellow River Delta of China as a low-cost raw material. The adsorption-desorption behavior of methylene blue (MB) onto the reed activated carbon (RAC) was studied in detail. The structure of RAC was characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and nitrogen adsorption analysis. Based on a good fitting with the Langmuir isotherm model, and pseudo second-order kinetics, the adsorption behavior of MB on RAC can be considered mainly to be the monolayer adsorption process, and is related to the chemical functional groups on the surface of carbon. The maximum adsorption capacity of RAC obtained from the Langmuir isotherm equation at 30 °C is 704.23 mg/g. The high adsorption capacity can be attributed to its low polarity, numerous types of surface functional groups, high surface area and pore volume, and a hierarchal porous structure. The regenerating rate of the spent RAC saturated with MB was 85.15% after one regeneration cycle, indicating a good potential for commercial applications.