Agricultural bamboo leaf waste as carbon precursor for the preparation of Cu-Al/biomass fiber adsorption and its application in the removal of ammonia nitrogen pollutants from domestic wastewater

Abstract

Biomass derived from the plant waste in the environment has been recognized as a potential source for preparing adsorbent in recent years. In this context, abandoned bamboo leaves from the surrounding area were collected and used as carbon precursor to prepare novel adsorbent for ammonia nitrogen removal. Bamboo leaves were treated with alkaline solution to produce biomass fiber (BF), then BF was reacted with aluminum nitrate nonahydrate and copper(ii) nitrate hydrate to form a Cu-Al composite oxide layer on the surface. Samples were well characterized by SEM, XRD and BET technique. The influencing factors including the pH, temperature, the time, and the dosage of adsorbent on the adsorption of ammonia nitrogen were studied. It was found that the maximum adsorption capacity toward ammonia nitrogen was fitted out to be 18.29 mg/g from the Langmuir isotherms model. In addition, the adsorbent showed outstanding total ammonia nitrogen removal in actual domestic sewage (Total ammonia nitrogen, TN, 12.6 ∼ 16.2 mg/L), which is significantly higher than that of the commercial activated carbon. Kinetics and thermodynamics studies indicated that the synergistic adsorption effect between biomass material and metal oxide plays a dominate role in the adsorption process. Therefore, the proposed strategy provides a promising way to deal with ammonia nitrogen wastewater and other types of water pollution. Besides, the reuse of surrounding plant waste is also consistent with the concept of green chemistry.