生理条件下PDF对Pb^(2+)、Cu^(2+)、Zn^(2+)、Ca^(2+)的吸附研究

Adsorption Study on PDF Pb^(2+)、Cu^(2+)、Zn^(2+)、Ca^(2+) under Physiological Condition

在生理条件下(pH2和pH7,37℃),用马铃薯膳食纤维(PDF)对金属离子Pb2+、Cu2+、Zn2+、Ca2+进行吸附试验。结果表明,两种酸度条件下PDF对Pb2+的吸附较大,对Cu2+、Zn2+的吸附较小,对Ca2+吸附很小;PDF用量增大(减小),吸附量(qe)减小(增大)。PDF对重金属离子的吸附表明PDF具有较好的生理活性。用作膳食纤维时应根据需求,按照已研究的用量与吸附量关系配制。其吸附作用是化学吸附与物理吸附的综合结果。PDF的疏松结构和红外光谱中较多的醛羧基团证明了这一点。吸附数据线形拟合表明物理吸附符合Ligniur单分子层吸附机理。

Under the physiological conditions (pH2 and pH7,37℃),the Potato Dietary Fiber(PDF) made by spent starchtaken from potato was used to test its adsorption to such metal ions as Pb2+、Cu2+、Zn2+ and Ca2+. The experiment showed,under two acidity conditions the adsorbing capacity of PDF to Pb2+ was stronger than that to Cu2+ and Zn2+, while that to Ca2+was the weakest. With the increase or decrease of dosage of PDF its adsorbing capacity (qe) to metal ions would decrease or increase.This proved that it has had a good physiological activation. Therefore, much attention should be paid to its dosage when it wasused as dietary fiber. The adsorption of PDF was the synthetic effect of both chemical and physical absorption, which could beproved by its loose structure and abundant aldehyde,carboxyl groups in Infrared Spectra.That data of adsorbing metal ions byPDF were linearly fitted in physical adsorption described by Langmuirr model.