Design and characterization of a biomass template/SnO2 nanocomposite for enhanced adsorption of 2,4-dichlorophenol

• Published in: Environmental research 2020-02, Vol.181, p.108955-108955, Article 108955
• Main Authors: Batool, Saima, Idrees, Muhammad, Ahmad, Munir, Ahmad, Mahtab, Hussain, Qaiser, Iqbal, Atef, Kong, Jie
• Format: Article
• Language: English
• Subjects: Active sites; Alternative adsorbents; Desorption efficiency; Nanomaterial; Phenolic compounds
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2019.108955

2,4-Dichlorophenol (2,4-DCP) is a hazardous chlorinated organic chemical derived from phenol that exerts serious effects on living organisms. In the present study, SnO2 templated with grapefruit peel carbon as a nanocomposite (SnO2@GPC) was designed via ball-milling, and its mechanism of 2,4-DCP adsorption in aqueous solution was determined. Batch adsorption experiments revealed that the maximum adsorption efficiency of SnO2@GPC occurred at 6.0 pH, 3 mg L−1 initial adsorbate concentration, 2 h contact time, and 293 K temperature. The SnO2@GPC nanocomposite and its non-tin-bearing counterpart, grapefruit derived char (@GPC), showed maximum adsorption capacities (QL) of 45.95 and 22.09 mg g−1 and partition coefficients of 41.77 and 10.83 mg g−1 μM−1, respectively. The adsorption of 2,4-DCP was best described by the Redlich−Peterson model followed by the Langmuir model with high correlation coefficients (R2 ≥ 0.96), and the adsorption kinetic data best fitted the pseudo-second-order model (R2 ≥ 0.98). The thermodynamic parameters indicated that the reaction was spontaneous, exothermic, and involved high affinity between SnO2@GPC and 2,4-DCP. The high desorption efficiency obtained (>80%) demonstrated the recyclability of the adsorbent. The enhanced QL of SnO2@GPC was due to the effective combination of GPC and SnO2. A thin porous layer of GPC on SnO2 nanoparticles provided effective channels, a large surface area, and an abundance of active sites for 2,4-DCP adsorption. Thus, the SnO2@GPC nanocomposite could potentially be used as a low-cost adsorbent to remove 2,4-DCP from water. [Display omitted] •A nano-composite was synthesized via simple single-step ball milling strategy.•The combined properties of SnO2 and GPC enhanced the removal of 2,4-DCP.•The removal was controlled by functional moieties of the composite and contaminant.•π-π electron-donor-acceptor connections with covalent bonding favored adsorption.