Biological manganese oxidation by Pseudomonas putida in trickling filters

ABSTRACT

Biological oxidation has been researched as a viable alternative for treating waters with high manganese (Mn) concentrations, typically found in mine drainage or in some geological formations. In this study, laboratory-scale trickling filters were constructed to compare the Mn removal efficiency between filters inoculated with the Mn oxidizing bacteria, Pseudomonas putida, and filters without inoculation. Manganese oxidation and removal was found to be significantly greater in trickling filters with Pseudomonas putida after startup times of only 48 h. Mn oxidation in Pseudomonas putida inoculated trickling filters was up to 75% greater than non-inoculated filters. One-dimensional advective-dispersive models were formulated to describe the transport of Mn in trickling filter porous media. Based on the experimental transport parameters obtained, the model predicted that a filter depth of only 16 cm is needed to reduce influent concentration of 10 mg L⁻¹ to 0.05 mg L⁻¹.

KEYWORDS:

• Biological treatment
• manganese oxidation
• trickling filter

Acknowledgments

The authors thank Dr. B. M. Tebo for generously donating Pseudomonas putida culture and Dr. S. Vaddiraju for providing SEM images of biogenic MnO₂.

Funding

CCV was supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1252521.