Characterization of Zinc Ion Adsorption onto Virgin and Calcined Lignin

摘要

In this study, virgin lignin (Lig) and calcined lignin at 200, 400, 600, 800, and 1000 °C (denoted by Lig200, Lig400, Lig600, Lig800, and Lig 1000) were used for development of selectivity adsorbent. The characteristics (SEM images, specific surface area, and surface functional groups etc.) of Ligs were investigated, and adsorption capability of zinc ion of ones from aqueous solution was evaluated. The specific surface area of Lig800 (306.3 m~2/g) was the largest of all Ligs. In addition, the acidic functional groups, that is, carboxyl groups and hydroxyl groups, on Ligs were loss at above 600 °C. The amount of zinc ion adsorbed was large in the order of Lig400 < Lig200 < Lig < Lig600 < Lig1000 < Lig800. The adsorption mechanism of zinc ion onto Ligs is estimated both an ion exchanges with protons and an adsorption in pore on Ligs. Moreover, amount of zinc ion adsorbed onto Lig800 increased with increasing adsorption temperatures (10 < 25 < 50°C), and that of zinc ion in single solution system was larger than in binary system (zinc ion and copper ion). These results indicate that the lignin has great potential for zinc ion adsorption from aqueous solutions.