Study on the preparation conditions and degradation performance of an efficient immobilized microbial agent for marine oil pollution

ABSTRACT

In the process of handling marine oil spills accidents, the biological method has attracted wide attention due to its low cost and no secondary pollution. However, in the process of practical application, there are problems such as low microbial density and great influence of environmental factors when the oil is treated by spraying microorganisms on the sea surface. This study used immobilized microorganism technology to solve the above-mentioned problems. In this study, the bacteria immobilized on cinnamon shell (CS) with good degradation performance were obtained by optimizing preparation conditions. Under the optimal conditions of sodium alginate (SA) concentration of 4.57%, CS concentration of 1.28%, and the CaCl₂ concentration of 2.45%, the degradation rate of diesel in 5 days reached 74.04%. The reusability of immobilized microbial agents was further studied. The study designed three cycles of repeated degradation experiments. The results showed that the degradation rate of diesel can still reach 60.12% after three times of reuse, which indicated the reusability of the immobilized microbial agents was excellent. The decrease in degradation rate of diesel was mainly related to the fragmentation of immobilized microbial agents and the decrease in microbial biomass.

GRAPHICAL ABSTRACT

KEYWORDS:

• Oil pollution
• Bioremedation
• Immobilization
• Preparation
• Reuse

Acknowledgements

This work was supported by the scientific research fund project of the National Natural Science Foundation of China under grant numbers 52070123; the Major Science and Technology Innovation Projects in Shandong Province under grant number 2019JZZY020808; the Open Research Fund Program of Shandong Key Laboratory of Eco-Environmental Science for Yellow River Delta (Binzhou University) under grant number 2019KFJJ02; Young Science and Technology Innovation Program of Shandong Province under grant number 2020KJD001; the Science and Technology Projects of Qingdao under grant number grant number 19–6–2–25-cg; and Project of Shandong Province Higher Educational Young Innovative Talent Introduction and Cultivation Team [Hydrogen energy chemistry innovation team].

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by National Natural Science Foundation of China: [Grant Number 52070123].