Vijayaraghavan K, Mao Juan, Yun Yeoung-Sang
Division of Environmental and Chemical Engineering, Research Institute of Industrial Technology, Chonbuk National University, Chonbuk 561-756, South Korea.
Bioresour Technol. 2008 May;99(8):2864-71. doi: 10.1016/j.biortech.2007.06.008. Epub 2007 Jul 30.
The amino acid fermentation industry waste, Corynebacterium glutamicum, has been found to possess excellent biosorption capacity towards methylene blue (MB). Due to practical difficulties in solid-liquid separation and biomass regeneration, C. glutamicum was immobilized in a polysulfone matrix. The pH edge experiments revealed that neutral or alkaline pH values favored MB biosorption. Isotherm experiments indicated that C. glutamicum, when in immobilized state, exhibited slightly inferior dye uptake compared to free biomass. Also considering the two forms, immobilized biomass took a long time to attain equilibrium. An attempt to identify the diffusion limitations in immobilized beads was successful, with the Weber-Morris model clearly indicating intraparticle as the rate controlling step. Regeneration of the free biomass was not possible as it tended to become damaged under strong acidic conditions. On the other hand, immobilized biomass performed well with 99% desorption of MB from the biosorbent with the aid of 0.1 mol/l HCl. The immobilized biomass was also successfully regenerated and reused for three cycles without significant loss in sorption capacity. An up-flow packed column loaded with immobilized biomass was employed for the removal of MB. The column performed well in the biosorption of MB, exhibiting a delayed and favorable breakthrough curve with MB uptake and % removal of 124 mg/g biomass and 70.1%, respectively.
已发现氨基酸发酵工业废弃物谷氨酸棒杆菌对亚甲基蓝（MB）具有出色的生物吸附能力。由于固液分离和生物质再生存在实际困难，谷氨酸棒杆菌被固定在聚砜基质中。pH边界实验表明，中性或碱性pH值有利于MB的生物吸附。等温线实验表明，谷氨酸棒杆菌固定化后，与游离生物质相比，染料摄取量略低。同时考虑到这两种形式，固定化生物质达到平衡需要很长时间。成功地尝试确定了固定化珠子中的扩散限制，Weber-Morris模型清楚地表明颗粒内扩散是速率控制步骤。游离生物质无法再生，因为它在强酸性条件下容易受损。另一方面，固定化生物质表现良好，借助0.1 mol/l HCl可从生物吸附剂中解吸出99%的MB。固定化生物质也成功再生并重复使用了三个循环，吸附容量没有明显损失。使用装有固定化生物质的上流式填充柱去除MB。该柱在MB的生物吸附方面表现良好，呈现出延迟且良好的穿透曲线，MB摄取量和去除率分别为124 mg/g生物质和70.1%。
