摘要
Screened atrazine-mineralizing bacterium―Pseudomonas W4 was embedded inside an improved PVA- H3BO3 embedment matrix to make bio-beads to degrade atrazine. The atrazine degradation characteristics were studied. The preparation procedure of bio-beads was as follows： （1） preparing a mixture of 100, 12.5, 10, 1.5 and 1 g/L PVA, bentonite（Ca）, activated carbon powder, sodium alginate and centrifuged Pseudomonas W4 bacterium, respectively; （2） the mixture was dropped into a gently stirred cross linker solution（pH=6.7） and cured at 10 °C for 24 h. The optimal atrazine degradation conditions by bio-beads were as follows： pH=7, the auxiliary carbon source was glucose, and the concentration of glucose was greater than 325 mg/L. The bio-beads demonstrated stronger tolerance ability than the free microorganism to the increase of PCBs, hydrogen ion and hydroxide ion. SEM images show the uniform distribution of the microorganism inside bio-beads and the porous cross-linked structure of bio-beads which provides excellent mass transfer capacity.
Screened atrazine-mineralizing bacterium―Pseudomonas W4 was embedded inside an improved PVA- H3BO3 embedment matrix to make bio-beads to degrade atrazine. The atrazine degradation characteristics were studied. The preparation procedure of bio-beads was as follows： （1） preparing a mixture of 100, 12.5, 10, 1.5 and 1 g/L PVA, bentonite（Ca）, activated carbon powder, sodium alginate and centrifuged Pseudomonas W4 bacterium, respectively; （2） the mixture was dropped into a gently stirred cross linker solution（pH=6.7） and cured at 10 °C for 24 h. The optimal atrazine degradation conditions by bio-beads were as follows： pH=7, the auxiliary carbon source was glucose, and the concentration of glucose was greater than 325 mg/L. The bio-beads demonstrated stronger tolerance ability than the free microorganism to the increase of PCBs, hydrogen ion and hydroxide ion. SEM images show the uniform distribution of the microorganism inside bio-beads and the porous cross-linked structure of bio-beads which provides excellent mass transfer capacity.
基金
Supported by the National Natural Science Foundation of China(Nos.40702039, 20090879029)
