Evaluating the interactions of organic compounds with multi-walled carbon nanotubes by self-packed HPLC column and linear solvation energy relationship

• Published in: Journal of hazardous materials Vol. 263; pp. 550 - 555
• Main Authors: Chu, Yingqian, Li, Xuehua, Xie, Hongbin, Fu, Zhiqiang, Yang, Xianhai, Qiao, Xianliang, Cai, Xiyun, Chen, Jingwen
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.12.2013; Elsevier
• Subjects: Adsorption; Applied sciences; Assessments; Carbon - chemistry; Chemical engineering; Chromatographic column; Chromatography - methods; Chromatography, High Pressure Liquid; Column packings; Electrons; Environmental Restoration and Remediation - methods; Exact sciences and technology; HPLC; Interactions; Kinetics; Mathematical analysis; Molecular Weight; Multi wall carbon nanotubes; MWCNTs; Nanotubes, Carbon - chemistry; Organic Chemicals - chemistry; Organic compounds; Pollutants; Pollution; Solvation; Solvents - chemistry; Thermodynamics; Water - chemistry; Thermodynamics; MWCNTs; Interactions; HPLC; Chromatographic column; Toluene; HPLC chromatography; Retention factor; Liquid chromatography; Pollutant; Adsorption; Thermodynamic parameter; Phenols; Affinity; Aromatic compound
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2013.10.010

•The HPLC-based approach using CNTs as stationary phase is introduced.•The interactions of nine compounds to MWCNTs are evaluated by retention factors.•The LSER theory is adopted to probe the interactions of the compounds with MWCNTs.•π-/n-Electrons-dependent polarizable interaction plays a key role for adsorption. Understanding the interactions between organic pollutants and carbon nanotubes (CNTs) is critical for fate assessment of both CNTs and organic pollutants. In this study, the chromatographic approach was introduced based on CNTs as stationary phase for the evaluation of such interactions. The pristine multi-walled carbon nanotubes (MWCNTs) were packed into columns of high-pressure liquid chromatography (HPLC) and the retention factors (k′) were determined to characterize the adsorption affinity of organic compounds onto MWCNTs. Nine compounds were tested. The results showed that their lnk′ values followed the order: benzene<toluene<phenol<chlorobenzene<bromobenzene<aniline<sulfamethoxazole<sulfadiazine≈sulfadimidine. The linear solvation energy relationship (LSER) theory was adopted to correlate lnk′ with the molecular solvatochromic parameters. We found that lnk′ of the studied compounds correlate positively with molecular polarizability (E) significantly, suggesting that the π-/n-electrons-dependent polarizable interactions play a major role for the adsorption. Moreover, the thermodynamic parameters calculated from van’t Hoff equations revealed that the interactions between the compounds and MWCNTs were spontaneous and exothermic processes.