硅藻土吸附固定化微生物对邻苯二甲酸二丁酯的降解特性研究

Biodegradation of dibutyl phthalate by diatomite adsorptive immobilized microorganism

目的研究以硅藻土作载体的播种式固定化微生物对邻苯二甲酸二丁酯(DBP)的生物降解特性。方法将改性硅藻土作为载体,制成吸附DBP降解优势菌的固定化微生物,然后在不同DBP初浓度、振荡速度、pH值、温度及重金属化合物存在的条件下对DBP进行降解试验,并进行降解动力学分析。结果在DBP初浓度为100～500mgL范围内,吸附固定化微生物对DBP的降解均保持较高的活性,24h降解率可达80%以上;游离与吸附固定化微生物在振荡条件下的降解活性高于静置时的降解活性;在pH值为6.0～9.0范围内,固定化微生物的活性均高于游离态微生物,24h的降解率可达82%以上;在20～40℃的温度范围内,固定化微生物24h降解率达84.5%;若试验水样中加入金属化合物,对游离和固定化微生物的降解活性均有明显的抑制作用;吸附固定化微生物对DBP降解过程可用一级反应动力学模型表达。结论硅藻土吸附固定化微生物,可有效降解DBP;吸附固定化微生物较游离态微生物对DBP负荷、温度、pH值具有更宽的适应能力;重金属化合物对其降解能力均有抑制作用;吸附固定化微生物对DBP的降解符合一级反应动力学模型。

Objective To study the biodegradation characteristics of seeding type immobilized microorganism on dibutyl phthalate（DBP）, Methods Tile immobilized microorganism was made to adsorb DBP degradation dominant bacteria by using modified diatomite as carrier, then it degraded DBP under different primary concentration, vibration rate, pH, temperature and at the presence of metal compounds. The degradation kinetics was analyzed. Results When DBP primary concentration was 100-500mg/L, the adsorptive immobilized microorganism could maintain relatively high activity and the DBP degraded rate was above 80% in 24h. Dissociative and immobilized microorganism could get higher degradation activity in vibration than in stillness. When pH was 6.0- 9.0, the degradation rate of immobilized microorganism on DBP was above 82% in 24h and its activity is higher than dissociative microorganism. In the range of 20℃ to 40℃, the DBP degraded rate by immobilized microorganism could reach 84.5% in 24h. If mental compounds existed in the DBP water sample, the degradation activities of dissociative and immobilized microorganism were inhibited obviously. The form of DBP degradation kinetics could be described as the first-order model. Conclusion The immobilized microorganisms using diatomite as carrier could degrade DBP effectively, The adsorptive immobilized microorganism was more adapted to DBP load, temperature and pH than dissociative microorganism, The mental compounds could inhibited their activities. The degradation reaction of adsorptive immobilized microorganisms on DBP was according with the first-order model.