Tetracycline removal by polyelectrolyte copolymers in conjunction with ultrafiltration membranes through liquid-phase polymer-based retention

• Published in: Environmental research 2020-03, Vol.182, p.109014-109014, Article 109014
• Main Authors: Palacio, Daniel A., Leiton, Lorena M., Urbano, Bruno F., Rivas, Bernabé L.
• Format: Article
• Language: English
• Subjects: Emerging pollutant; Membranes; Polyelectrolyte; Removal; Tetracycline
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2019.109014

In this study, we used a liquid-phase polymer-based retention technique assisted by polyelectrolyte copolymers containing quaternary ammonium and sulfonate groups that are capable of removing the antibiotic tetracycline (TC) through electrostatic interactions. The polymers were synthesized using zwitterionic, anionic, and cationic monomers with the aim of obtaining copolymers with different charge balances at the ratios of 1:1, 2:1, and 1:2 (negative: positive). The parameters investigated for each copolymer included the pH, ionic strength, concentration of polymer, maximum retention capacity, and sorption–elution process at pH 11.0 and 3.0. The copolymers with a charge ratio of 1:2 achieved the highest retention (80.0%) at alkaline pH, while the copolymers with charge ratios of 2:1 and 1:1 exhibited the maximum retention (72.0%) at acidic pH. Based on these results, the pH and charge of the polyelectrolyte copolymers play important roles in the TC removal processes. Additionally, the maximum retention capacity (MRC) recorded was 731.2, 176.8, and 214.8 mg TC/g of copolymer in the first charge for the three copolymer polyelectrolytes, and the second charge of the MRC process did not improve compared with the first load. [Display omitted] •The LPR is an effective technique to remove tetracycline from aqueous effluents.•The charge ratio of copolymers displays a significant effect on tetracycline retention.•Copolymer P(HMPSA-co-ClVBTA) achieved the highest retention capacity of 732 mg TC/g of polymer.•The LPR is an attractive technique of easy operation and low energy consumption.•The polyelectrolytes removed approximately 70% and 80% of tetracycline.