摘要
以胶原纤维为基质,通过交联剂将黑荆树单宁、落叶松单宁和毛杨梅单宁固化在胶原纤维上制备吸附材料。实验表明,3种固化单宁对Cu2+的吸附平衡均符合Freundlich方程,其吸附容量大小顺序为:固化毛杨梅单宁>固化黑荆树单宁>固化落叶松单宁。进一步研究了固化黑荆树单宁的吸附动力学、吸附柱动力学,以及温度、pH值等对吸附平衡的影响。结果表明,温度对吸附平衡的影响不明显,但pH值对吸附平衡有较大影响,在适当范围内提高pH值,会增加平衡吸附量;吸附动力学可用拟二级速度方程来描述,当吸附温度≥318K时,由拟二级速度方程计算所得到的平衡吸附量与实测的平衡吸附量非常吻合。固化单宁具有良好的柱动力学特性,吸附柱极易再生并且能循环使用,吸附过程极有可能是在材料的表面进行。
Using collagen fibre as matrices,the immobilized tannins adsorbents based on black wattle,larch and myrtan tannins were prepared through crosslinking reaction.As novel adsorbents,their ability of recovering Cu 2+ from waste water was studied.Experiments showed that adsorption isotherms of immobilized tannins for Cu 2+ could be described by Freundlich model and their adsorption capacities were in the sequence of:immobilized myrtan tannin> immobilized black wattle tannins>immobilized larch tannin.Furthermore,adsorption characteristics of immobilized black wattle tannin that has higher thermal stability were investigated in details.It was found that influence of temperature on adsorption isotherms was not obvious,whilst effect of pH value was significant.Higher pH value of solution led to higher equilibrium adsorption capacity.Data of adsorption rate could be well fitted by pseudo second order rate model,and adsorption capacity calculated by the model was consistent with actual measurement,particularly when adsorption temperature higher than 318 K was employed.Studies also indicated that the immobilized black wattle tannin had excellent properties of column adsorption kinetics,as well as highly effective availability of adsorption column. Meanwhile ,no considerable change of column adsorption property was observed after adsorption desorption cycles,probably due to the fact that adsorption process takes place at the surface of adsorbent.
出处
《林产化学与工业》
EI
CAS
CSCD
2003年第4期11-16,共6页
Chemistry and Industry of Forest Products
基金
中国高校博士点基金资助项目(20020610010)
