Entrapment of Pseudomonas putida in chitosan beads for phenol degradation

• Main Authors: Feng-Ming Hsieh, 謝峰銘
• Other Authors: Jui-Che Lin
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/74295418444640572874

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 94 === This study was aimed to investigate the efficiency of phenol degradation by Pseudomonas putida CCRC14349 that was entrapped within the gel beads prepared by chitosan crosslinked with sodium tripolyphosphate. In addition, various characteristics of these beads were evaluated as well. The efficiency of phenol degradation for the entrapped cells was optimized by changing various processing parameters, such as the amount of cells used, beads washing medium as well as acclimatization strategy. Based on the batch phenol degradation results, these entrapped cells were found to be superior to the free cells in terms of keeping the solution clear, improving the toleration to the environmental loadings (e.g., high pH, low ionic strength, high phenol concentration), and repeating usage for an extended period. After phenol acclimatization, the structure of cell-entrapped beads showed to be stable under acidic and high ionic strength conditions. Diffusion coefficient calculation has indicated that phenol degradation by the entrapped cells varied from the intraparticle diffusion control to reaction control as the beads were used repeatedly. With the increase of hydraulic retention time and the addition of hydrogen peroxide to increase the dissolved oxygen level for cell metabolism, phenol in the influent was almost completely degraded in the packed-column test.