Microplastics & organics - a comparative study of sorption of triclosan and malachite green onto polyethylene

Ciftci G., Turkeli U. D., Ozen E. Y., Ozdemir M., SANİN F. D., İMAMOĞLU İ.

WATER SCIENCE AND TECHNOLOGY, vol.87, no.5, pp.1072-1081, 2023 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 87 Issue: 5
  • Publication Date: 2023
  • Doi Number: 10.2166/wst.2023.040
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Analytical Abstracts, Aqualine, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chimica, Compendex, EMBASE, Environment Index, Geobase, Pollution Abstracts, Public Affairs Index, Veterinary Science Database, Directory of Open Access Journals
  • Page Numbers: pp.1072-1081
  • Keywords: hydrophobic interaction, malachite green, mechanism, microplastics, sorption, triclosan, ADSORPTION, CHLORIDE
  • Middle East Technical University Affiliated: Yes


This study aims to elucidate interaction of organics with microplastics in a comparative manner via the use of two model compounds (i.e., triclosan and malachite green) having different physicochemical properties, onto polyethylene (PE). TCS, is hydrophobic with low solubility , while MG is hydrophilic with high aqueous solubility. Kinetic studies indicate faster sorption (t(eq) = 24 h) and equilibrium studies show much higher capacity (q(e) = 6,921 mg/g) for TCS, when compared to those of MG (t(eq) = 5 d, q(e) = 221 mg/g). While pseudo-kinetic model fits sorption of both organics to PE, equilibrium isotherms as well as the results on effect of particle size and pH indicate dissimilar sorption mechanisms. Considering pH(PZC)= 2, observation of favourable sorption of TCS in acidic region and sorption being unaffected by particle size was explained by TCS sorption to be dominated by hydrophobic interactions in amorph regions of PE. Higher removal of MG was observed at lower surface charge of PE, and a clear favourable impact of surface area on MG sorptive capacit y pointed to the presence of non-specific van der Waals type interactions on the surface of PE. Mechanistic evaluations presented here contribute to our understanding of interaction of MPs with organics in aquatic ecosystems.