Bruce L J, Chase H A
Department of Chemical Engineering, University of Cambridge, UK.
Bioseparation. 1999;8(1-5):77-83.
An expanded bed adsorption (EBA) column (5 cm diameter) has been modified to allow the abstraction of liquid samples from various positions along the height of an expanded bed. As the adsorbent particles were fluidized, in-bed monitoring of key component concentrations during feedstock application, washing and elution was achieved by the withdrawal of liquid samples from the voids within the expanded bed through ports along the wall of the column. Component levels in the withdrawn streams can be assayed using on-line analytical chromatography or samples can be collected and assayed off-line. On-line monitoring can be used to control the duration of the loading stage and as a tool to provide information about the hydrodynamic and adsorption/desorption processes that occur during expanded bed adsorption. Studies of residence time distributions indicated that the modifications to the column do not significantly affect liquid dispersion. Using the adsorption of glucose-6-phosphate dehydrogenase from yeast homogenate on Streamline DEAE as a model system, comparison of breakthrough curves for runs when in-bed monitoring was and was not performed also suggested that separation efficiency is not appreciably affected by in-bed sampling.
一个膨胀床吸附（EBA）柱（直径5厘米）已被改造，以允许从膨胀床高度的不同位置提取液体样品。当吸附剂颗粒流化时，在原料应用、洗涤和洗脱过程中，通过沿柱壁的端口从膨胀床内的空隙中抽取液体样品，实现了对关键组分浓度的床内监测。抽出物流中的组分水平可以使用在线分析色谱法进行测定，或者可以收集样品并离线测定。在线监测可用于控制加载阶段的持续时间，并作为一种工具，提供有关膨胀床吸附过程中发生的流体动力学和吸附/解吸过程的信息。停留时间分布的研究表明，对柱子的改造不会显著影响液体分散。以酵母匀浆中葡萄糖-6-磷酸脱氢酶在Streamline DEAE上的吸附作为模型系统，对进行床内监测和未进行床内监测时运行的穿透曲线进行比较，也表明床内采样对分离效率没有明显影响。
