Lead Ions Removal Using Pineapple Leaf-Based Modified Celluloses

Abstract

Pineapple leaves are largely discarded in the harvest area and considered as agricultural waste. Herein, the extracted pineapple leaves fiber was altered with chelating agents to become an adsorbent for lead ions (Pb²⁺) removal from aqueous solutions. The initial investigation determined that the most appropriate conditions for extracting cellulose fiber from pineapple leaves were stirring at 90–100 °C in 10%w/v NaOH for 1 h. Next, carboxymethyl, amide, and amidoxime were used to modify with the extracted cellulose fiber, denoted as Cell-CMC, Cell-AM, and Cell-AMX, respectively. At pH 6, Cell-CMC, Cell-AM, Cell-AMX, and the extracted cellulose fiber had maximum adsorption potential values of 9.3, 1.5, 3.6, and 6.3 mg g^–1, respectively. In the kinetic analysis, Cell-CMC, Cell-AM, and extracted cellulose adsorption behaviors were well represented using a model of pseudo 1^st order, while the adsorption behavior of Cell-AMX was best represented using a model of pseudo 2^nd order. Further investigation demonstrated that the desorption efficiency of each adsorbent increased as the pH value was lowered from 3, 4, and 6.