Immobilization Of Comamonas Sp.bdq06 On PES Beads For Degrading Quinoline In Water

Under the development of specific strains or agent, the carriers, which were suitable for growth and attachment, became a new research hotspot and attracted attention of environmental scholars. Previously, when it came to the specific strains, its degradation efficiency depended on reproduction and dissociate conditions. Recently, the application of immobilized technology provided a tiny room to immobilize the specific strains, could solve the byprodut brought by mixing the solution and shear stress brought by aeration. It could assure the positive specific strains growth and reproduction and improve the amounts of specific strains, decreasing and preventing the mass loss. Meanwhile, the immobilized technology could strength the adaptability of the specific strains and improve relative abundance of microbes to increase themicrobial treatment efficiency of wastewater.In this study, we had prepared ethyl cellulose microcapsules, silica beads and PES pellets,successively, and compared their production methods and performance. Finally, we chose to PES pellets to load bacteria to degrade organic matter in water and obtained the following conclusions:The ethylcellulose microcapsules, which was made by water drying method, had a porous surface with uneven distribution and size.it was difficult to obtain due to the preparation conditons. Silicon beads obtained from dropped the sodium silicate solution to the tube, had rich porous structure and well adsorption performance. However, when the above silica beads were put into water with a long immersion time, it might deform or even dissolve.The PES pellets were made by impregnated precipitation phase inversion method with using olyether sulfone as raw material. It had a diameter of about 3 mm, the surface was smooth legal system and the internal structure was porous. Meanwhile, the pellets surface had a layer with a thickness of 20 μm. This dense layer would prevented the bacteria getting into the interior of PES pelldts from the surface to weaken the protective effect of the carrier on the bacteria. So, this sdudy also conducted an improved optimizative method for preparing PES.We chose theorganic solvent(N, N- dimethylformamide) to erode the densified layer to expose the interior. This procedure made the surface presenting lots of pores with a diameter of 1.5μm. The size of these pores increased from the inside out and made the attachment of bateria easily by providing a better place to reproduction and growth.The bacteria in this study was isolated from the sludge of sewage treatment plant. It was identified as a testosteroni sp(Comamonas testosteroni sp. Bdq06). Put the testosteroni sp and PES pellets into the solution with quinoline and salts, and get PES pellets loading with testosteroni sp after 12 h.We used the PES beads loading with testosteroni sp to degrade the quinoline in the working solution under different conditions. Comparing with the degradation efficiency of the free bateria, the PES beads loading with testosteroni sp had a better degradation efficiency at the p H=5 or 10 and T=40 ℃. When the p H was 7, both the two materials had the same degradation efficiency substantially. When the p H was 10, the PES beads loading with testosteroni sp could degrade the quinoline completely in 15 h.At the same time, the degradation efficiency of quinoline degraded by the free bateria only achieved 16.3%, and when it degraded completely, it needed another 9 h. when the temperature was 40 ℃, the PES beads loading with testosteroni sp could degrade the quinoline with a number of 78.6%, and the free bateria had the removal efficiency of 37.7%. when the p H was low than 5, the free bateria was diffcult to grow because of the change of surface charge and had a low degradation efficiency of 30% in 24 h, meanwhile, the PES beads loading with testosteroni sp could degrade the quinoline compeletely and had an obviously advantage.PES beads still had good mechanical strength and swelling resistance after repeated using without rupture. A large number of bacteria on the surface formed biofilm through reproduction and growth and improve the efficiency of degradation significantly. 100 mg / L quinoline solution could be completely degraded within 2 h with a certain dose of PES beads. The pellets with using polyether sulfone as the raw material had potential applications in water treatment, especially in the extreme conditions.