Biodegradation Of Tetrahydrofuran By Immobilized Predominant Strain Pseudomonas Oleovoransdt4

Tetrahydrofuran (THF), a cyclic ether organic compound called "all-purpose solvent", is widely used in the manufacture and processing of coating, leather making, medicine and so on. With the development of national economy, the demand of THF is increasing annually, inevitably resulting in the environmental pollution. As a result, it is crucial to explore effective methods for the removal of THF in the environment. This work was aimed to immobilize predominant strain Pseudomonas oleovorans DT4by the synergy immobilized technology, and to investigate the character of the immobilized beads group in batch or continuous flow system.Calcium alginate was selected as the immobilized microbial carrier among agar, calcium alginate, polyvinyl alcohol and polyacrylamide based on the activity of cell and the mechanical strength of particle. Compared with kieselguhr and powdered activated carbon, the activated carbon fiber was selected as the carrier’s additive, and the synergy immobilized beads of the calcium alginate and activated carbon fiber were greatly enhaced. After researching its degradability and mechanical strength, the more suitable immobilized method is confirmed:3%sodium alginate,4%CaCl2,1.5%activated carbon fiber and3210.9mg/L bacterium suspension. Due to the coupling of the adsorption and the biodegradation in the synergy immobilized beads, THF removal rate was enhanced. The comparative study of characters of immobilized cells and free cells sugguested that the adaptable range of immobilized cells on pH value, temperature and initial THF concentration was widened, and the stability became stronger. The removal rate is still above70%after10times’consecutively use of the immobilized beads. The packed-bed reactor was designed, and the continuous biodegradation of THF is achieved. Under the conditions of the influent concentration50mg/L hydraulic retention time3000s, and ventilation10%, THF removal rate can be steadily above93%. But after12d, THF removal rate continually descend, only50%on20th day, probably for the cells’leakage.