直接溶解法制备纤维素/碳化钨复合扩张床基质  

Preparation of cellulose/tungsten carbide composite beads with direct dissolution method for expanded bed application

作　　者：PHOTTRAITHIP Wimonrat 王志远 林东强[1] 姚善泾[1] 

机构地区：[1]浙江大学化学工程与生物工程学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2010年第5期998-1002,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家"863"高技术研究发展计划资助项目(2006AA02Z21);国家自然科学基金资助项目(20776129)

摘　　要：以精制棉为原料,采用N-甲基吗啉-N-氧化物(NMMO)直接溶解纤维素,制备纤维素/NMMO/H2O溶液,添加碳化钨作为惰性增重剂,通过反相悬浮和程序降温制备成纤维素/碳化钨复合微球.结果表明,NMMO溶解法制备的纤维素/碳化钨复合微球球形度好,在介质中的密度达到1.6～2.4g/mL,孔度约为70%,平均孔径为25nm,比表面积为60～70m2/mL,微球粒径具有明显的对数正态分布.扩张床内扩张性能良好,Bo准数大于40,轴向扩散系数处于10-6数量级,床层稳定,可以作为扩张床吸附剂(EBA)的基质.与商业介质Streamline相比,在相同扩张率下,本文制备的扩张床基质可以用于较高的流速,满足扩张床吸附的高处理量要求.The refined cotton was dissolved in N-methylmorpholine-N-oxide （NMMO） solution to prepare the cellulose/NMMO/H2O viscous solutions. Using the reversed-phase suspension and the sequential cooling technique,the spherical cellulose composite beads were prepared with cellulose/NMMO/H2O solution and tungsten carbide powder as the inert densified component. Results indicated that the composite beads had regular spherical appearance,the relative high density of 1.6～2.4 g/mL,the porosity of 70%,the mean pore diameter of 25 nm,the specific surface of 60～70 m^2/mL,and the suitable logarithmic symmetrical size distribution. The composite beads showed good expansion in the column,with Bo number above 40 and the axial dispersion coefficient at the order of 10^-6 magnitude,which can meet the demand of expanded bed adsorption （EBA）. Compared with the commercial Streamline adsorbent for EBA,the composite beads can be used at higher flow rate,resulting in the relative higher throughout for EBA process.

关 键 词：复合基质 纤维素 N-甲基吗啉-N-氧化物 碳化钨 扩张床吸附 

分 类 号：TQ028.8[化学工程]