摘要
将交联壳聚糖季铵盐用于水体中NO3-的吸附去除,考察了pH、共存阴离子对吸附过程的影响以及吸附剂的重复使用性能,并对吸附过程进行了动力学和吸附等温模型分析。结果表明,当溶液的pH在3.5～10.2之间时,pH对吸附过程的影响较小;水体中共存阴离子会与NO3-产生一定的竞争作用,其影响顺序为:Cl->SO42->HCO3-;该吸附反应非常迅速,吸附主要发生在反应前1 min内,且在10 min内达到吸附平衡;该吸附过程符合准二级动力学模型,化学吸附为吸附的主要速率控制步骤;吸附过程符合Freundlich吸附等温模型,表明吸附过程以均相吸附反应为主;同时,该吸附剂具有很好的再生性能,1%的NaCl再生液可迅速、高效地实现饱和吸附剂的再生。
Cross-linked quaternary chitosan salt was used to adsorb nitrate from water. The effect ofpH and co-existing anions on the adsorption process, adsorption isotherms and kinetics, and its regeneration ability were investigated by batch experiments. The effect ofpH on the adsorption process was not significantly in a range from 3.5 to 10.2. The effect of co-existing anions on nitrate adsorption followed the order： C1〉 SO4^2〉 HCO3. The adsorption reaction was fast and it could reach to reaction equilibrium within l O min. The adsorption data fitted Tempkin isotherm model and Pseudo-second-order model well, which showed that chemical adsorption was a rate-limiting stage during the adsorption process. The spent adsorbents could be regenerated by NaC1 solution with the.concentration of 1% effectively and fast. These results suggest that the cross-linked chitosan quaternary ammonium salt provides a promising method for nitrate removal from water.
出处
《水处理技术》
CAS
CSCD
北大核心
2012年第9期21-25,共5页
Technology of Water Treatment
基金
国家自然基金(51109019)
关键词
交联壳聚糖季铵盐
硝酸盐
吸附
再生
cross-linked quaternary chitosan salt
nitrate
adsorption
regeneration
