The Preparation Of Cotton Cellulose Anion-exchange Fiber And Adsorbent

Cotton cellulose is a kind of naturalsupermolecular polymer with a high degreeof crystallization, which makes other reagent so difficult to contact with the hydroxy incellulose molecule, therefore it becomes more difficult to modify cellulose. Based on it,Research on preparing cellulose anion exchange fiber and adsorbent is discussed in thisdissertation. 1. The selection of solvent Various kinds of reagents are added in the solution of NaOH to form some kinds of blendsolvent, which is used to react with cellulose. After that, it reacts with epichlorohydrin.Through testing the epoxide number of the cellulose ether, the influence of the reagents addedin the solution of NaOH is determined. In the end, two kinds of the solvent systems arechosen: NaOH-urea-isopropanol blend solvent and NaOH-isopropano-DMSO blend solvent.Then the orthogonal experiments on the reaction between these two kinds of blend solventand cellulose are made and the important influential factors to the reactions are founded.Furthermore, the better process condition of the reactions and mixing proportion of thereagent in the blend solvent are decided. 2. The preparation of cellulose anion-exchange fiber and adsorbent Three schemes to prepare cellulose anion-exchange fiber and adsorbent are designed. ⑴ The method of fractional steps According to the processes of alkalizing cellulose, cross linking and etherifying alkalicellulose, aminating etherified cellulose etc, The preparation of cellulose ion-exchanger fiberis systematically researched, including the reaction conditions for cross linking andetherifying of alkali cellulose. and the orthogonal experiments of aminizating etherifiedcellulose. So the better technical conditions are decided. The final product produced by this2002 届中北大学硕士学位论文 棉纤维素阴离子交换纤维及吸附剂的制备process has an exchange capacity of 0.49 mmol·g-1 and the adsorption capacity for dye is186mg·g-1. ⑵ One step method After reacting with the blend solvent, cellulose is directly cross linked and etherified,then aminizated. That is to produce ion-exchanger fiber and adsorbent by one step,Meanwhile the reaction process conditions are discussed, the final product has an exchangecapacity of 0.57 mmol·g-1 and the adsorption capacity of 197mg·g-1 respectively. ⑶ In anhydrous conditions After alkalization, cellulose reacts with epichlorohydrin in anhydrous conditions. Thentriethylamine is added. The cellulose adsorbent produced in this way has an exchangecapacity of 0.1 mmol·g-1 and an adsorption capacity of 217mg·g-1 respectively. ⒊ Testing By different ways, such as FRI and SEM etc, the final products produced by differentalkali cellulose and process conditions are analyzed, which proves that the solvents inproducing alkali cellulose play an important role in structures of the final products. ⒋ Application of the products By testing the adsorption capacity of cellulose anion exchange fiber for phenol ,it has anadsorption capacity of 39.92 mg·g-1, and the regenerationsolvent is gotten. Our studies provide the basic data of preparing the cotton cellulose ion-exchanger andadsorbent, and the productions can be used in the field of treating wastewater.