Applying MgO‐modified date tree fiber as a nanoadsorbent for nitrate removal from water

Abstract

AbstractModified date tree fiber has been applied as a nanoadsorbent to remove nitrate ion from wastewater. When the nitrate concentration in drinking water is more than a significant amount, nitrate removal will be a technical challenge. Since correction of the adsorbent surface by metals and metal oxides can significantly increase its adsorption capacity, nano‐adsorbent production using hard and porous fibers of date palm, was corrected by adding MgCl2·6H2O. Consequently, the formation of MgO particles with the dimension of 17.34 nm increased the adsorbent contact with water pollutants. The nitrate adsorption is by forming MgO layers on cellulose and hemicellulose as constituents of the fibers which with their hydroxyl groups, create a high potential for nitrate and even other oxanions removal in water through interaction between magnesium ion and empty spaces in the structure of fiber. Examining the pH of process as an influential factor, we found that pH 5 is the optimum value for having a maximum adsorption. The adsorption capacity, 55.30 mg·g−1 of MgO‐date tree fiber with a removal efficiency of about 90% indicates a high ability of removal. Moreover, a decrease of 0.05 mg g−1 in the capacity of nano‐adsorbent and 0.09% efficiency reduction of nitrate removal indicates the regeneration and reproducibility of the nano‐adsorbent after four cycles of adsorption and desorption. Therefore, the adsorbent obtained from carbon fiber of date tree modified with magnesium oxide as a novel inexpensive nano‐bio‐adsorbent recycled from native agricultural wastes will have the potential to significantly remove nitrate from wastewater.