表面結構肟基化之微結晶纖維素吸附水中之鐵離子

Surface Functionalization of Microcrystalline Cellulose for Sorption of Iron ions from Water

本研究之目的係表面改質微結晶纖維素，將能與重金屬離子錯合鍵結反應之肟基引入微結晶纖維素表面結構，以吸附水溶液中的鐵離子。本研究利用過碘酸根氧化與席夫置換兩個化學反應步驟，將微結晶纖維素表面結構之雙羥基轉換成為肟基。表面改質反應造成微結晶纖維素官能基之含量變化經化學定量分析，表面改質之微結晶纖維素單位質量之肟基含量為1.26 × 10^(-3) mol/g。利用含肟基之微結晶纖維素於pH值約為2的酸性水溶液中，以平衡吸附方式，吸附不同濃度的二價與三價鐵離子。吸附實驗結果顯示，含肟基之微結晶纖維素對水中二價與三價鐵離子之吸附，主要經由以一個肟基錯合鍵結一個鐵離子的結構。

The objective of the present study is to employ the surface-functionalized microcrystalline cellulose to collect Iron ions from water. The surface-functionalized microcrystalline cellulose was derived by using two chemical reactions to transform part of the surface structure of a commercial microcrystalline cellulose into oxime groups. Oxime groups are capable of selectively forming complexes with Iron ions. The two chemical reactions used for the surface functionalization are the periodate oxidation and the Schiff replacement reactions. The quantity of oxime groups of the surface functionalized cellulose was determined to be 1.26 × 10^(-3) mol/g of the cellulose mass. The equilibrium sorption experiments were performed for acidic aqueous solutions of the pH value around 2 with various concentrations of Iron ions (Ferrous and Ferric ions). The sorption results suggest that the surface functionalized cellulose collects Iron ions from water via forming a complex of one oxime group bonding with one Iron ion.