摘要：A new ion-exchange resin was prepared from cassava stalk for the effective removal of phosphate ions from wastewater. The cassava stalk quaternary amino anion exchanger (CS-QE) could be prepared through a 3-step sequential synthetic reaction among the activated cellulose of cassava stalk (CS) with epichlorohydrin (ECH), ethylenediamine (EDA) and triethylamine (TEA) in the presence of N,N-dimethylformamide (DMF). The reaction conditions were optimized by varying the amounts of EDA and TEA, controlling reaction temperatures and adjusting incubation times in the steps of activating, cross-linking and grafting. The synthesized resins were characterized by FT-IR, SEM, elemental analysis, and Zeta potential to determine their applicability in phosphate binding. The capacity of the new resin for phosphate removal was determined from two significant experimental indicators: the phosphate removal efficiency and zeta potential of the new resin, respectively. The results showed that (1) the optimal reaction ratio was CS:EDA:TEA = 2 g:1.8 g:3.7 g (or 2 g:3 ml:5 ml), (2) the activating, cross-linking and grafting times were 1, 0.5 and 4 h, respectively, and (3) the reaction temperature was 100 °C. The key influential factor on the preparation of CS-QE was found to be the TEA amount. Under the optimum conditions, the CS-QE with 94.7% of phosphate removal efficiency and 41.4 of zeta potential was obtained. The results in this study demonstrated that a new ion-exchange resin could be prepared from cassava stalk in a cost-effective way and used for the effective removal of phosphate ions from wastewater.
