Immobilization of phenanthrene onto gemini surfactant modified sepiolite at solid/aqueous interface: Equilibrium, thermodynamic and kinetic studies

Shan Zhao; Guohe Huang; Sen Mu; Chunjiang An; Xiujuan Chen

doi:10.1016/j.scitotenv.2017.04.120

Immobilization of phenanthrene onto gemini surfactant modified sepiolite at solid/aqueous interface: Equilibrium, thermodynamic and kinetic studies

Sci Total Environ. 2017 Nov 15:598:619-627. doi: 10.1016/j.scitotenv.2017.04.120. Epub 2017 Apr 25.

Authors

Shan Zhao¹, Guohe Huang², Sen Mu³, Chunjiang An⁴, Xiujuan Chen⁴

Affiliations

¹ Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China; Institute for Energy, Environment and Sustainable Communities, University of Regina, Regina, Saskatchewan S4S 0A2, Canada.
² Center for Energy, Environment and Ecology Research, UR-BNU, Beijing Normal University, Beijing 100875, China; Institute for Energy, Environment and Sustainable Communities, University of Regina, Regina, Saskatchewan S4S 0A2, Canada. Electronic address: huang@iseis.org.
³ Yunnan Electric Test & Research Institute Group Co., Ltd., Yunnan 650217, China.
⁴ Institute for Energy, Environment and Sustainable Communities, University of Regina, Regina, Saskatchewan S4S 0A2, Canada.

PMID: 28454034
DOI: 10.1016/j.scitotenv.2017.04.120

Abstract

The immobilization of phenanthrene from aqueous phase onto natural and gemini surfactant modified sepiolite was investigated with respect to contact time, pH, ionic strength and temperature. The surface modification was examined through FT-IR characterization, SEM technique, and the thermogravimetric analysis. The maximum sorption capacity of phenanthrene on modified sepiolite was 95.15μgg^-1 with initial PHE concentration 1.0mgL^-1, temperature 293K, pH7, and ionic strength 1M. The corresponding PHE removal efficiency was higher than 95%. The Langmuir, Freundlich and Temkin isotherm models were applied to describe the phenanthrene sorption behavior and the Freundlich equation agreed well with the experimental data. The evaluation of the thermodynamic parameters indicated that the immobilization of phenanthrene onto gemini surfactant modified sepiolite was a spontaneous and exothermic process from 283 to 313K. The pseudo-first-order, pseudo-second-order, Elovich, and intraparticle diffusion models were used to evaluate the kinetic data. According to the calculated kinetic parameters, the immobilization process of phenanthrene followed the Elovich kinetic model with the highest correlation coefficients. The obtained results show that gemini surfactant modified sepiolite could be effectively utilized as one type of low-cost clay material to remove polycyclic aromatic hydrocarbons from water effluents.

Keywords: Gemini surfactants; Immobilization; Kinetics; Phenanthrene; Sepiolite; Thermodynamics.