Separation and concentration of o–toluidine and tricyclazole from water with micellar enhanced ultrafiltration based on sodium dodecyl sulfate surfactant

ABSTRACT

Micellar enhanced ultrafiltration (MEUF) of o-toluidine and tricyclazole in aqueous stream using polyethersulfone (PES) hollow-fibre membrane of 6 kDa molecule weight cut-off (MWCO) and sodium dodecyl sulfate (SDS) as anionic surfactant was studied. It was found that the concentration ratio and adsorption ratio were better for the determination of the optimal pollutant or surfactant concentration than the rejection rate. The excessive dosage of surfactant had only limited effect on the separation and concentration of o-toluidine and tricyclazole but could further decrease the permeate flux. The transmembrane pressure had a significantly positive effect on the permeate flux and recovery ratio. o-Toluidine was significantly separated and concentrated by lowering the solution pH, while tricyclazole reached the best treatment efficiency in near-neutral pH condition. The sodium salts (i.e. Na₂SO₄, NaCl and Na₂CO₃) could lead to the increase in the adsorption ratio of SDS. However, Na₂CO₃ could result in the decrease in both the rejection rates and adsorption ratios of o-toluidine and tricyclazole. The distribution coefficient, micellar loading and micelle binding constant were evaluated to confirm the effectiveness for the MEUF treatment of these two pollutants.

GRAPHICAL ABSTRACT

KEYWORDS:

• Micellar enhanced ultrafiltration
• o-toluidine
• tricyclazole
• rejection rate
• concentration ratio

Acknowledgements

This work was supported by the grants from Science & Technology Department of Sichuan Province of China for the key research project (No. 2017SZ0175) and key special project (No. 2018SZDZX0026). Yiqing Liu also acknowledgments the financial support from the Fundamental Research Funds for the Central Universities (No. 2682018CX32). We are thankful to anonymous reviewers for their helpful suggestions.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Yongsheng Fu http://orcid.org/0000-0003-1944-8780

Additional information

Funding

This work was supported by the Fundamental Research Funds for the Central Universities: [Grant Number 2682018CX32]; Science and Technology Department of Sichuan Province of China: [Grant Number 2017SZ0175, 2018SZDZX0026].