Potential of aquatic plants for phytofiltration of uranium-contaminated waters in laboratory conditions

João Pratas, Carlos Paulo, Paulo J.C. Favas, Perumal Venkatachalam. Ecological Engineering, Volume 69, August 2014, Pages 170-176

Highlights

- This work focused on uranium (U) accumulation by aquatic plants in laboratory.

- A phytofiltration prototype was tested to reduce the U concentration in waters.

- All tested species showed high U bioaccumulation and high uptake kinetics.

- The results show a reduction of U concentration in water with an efficiency of 85.5%.

Abstract

This study presents the results of laboratory experiments, including a prototype phytofiltration system, to reduce the uranium (U) concentration in contaminated waters. The species Callitriche stagnalis Scop., Potamogeton natans L. and Potamogeton pectinatus L. of the native plant community of the uraniferous Beiras (Central Portugal) region were selected because they are autochthonous and they show high accumulation levels and/or high biomass production. The installed prototype consists of a closed circuit of channels. The system was initially contaminated with 500 μg/L of U as uranyl. The performance of this system was very effective. The U concentration in the water dropped to 220 μg/L in 24 h and after two weeks it had decreased to 72.3 μg/L. The U concentration increased in C. stagnalis from 0.98 to 1567 mg/kg, in P. natans from 3.46 to 270.9 mg/kg and in P. pectinatus from 2.63 to 1588 mg/kg. The results show the effectiveness of these plants in removing U from the water.