ARTICLE IN PRESS JID: JTICE [m5G;November 30, 2016;7:17] Journal of the Taiwan Institute of Chemical Engineers 000 (2016) 1–11 Contents lists available at ScienceDirect Journal of the Taiwan Institute of Chemical Engineers journal homepage: www.elsevier.com/locate/jtice Carbon fiber embedded chitosan/PVA composites for decontamination of endocrine disruptor bisphenol-A from water Esra Bilgin Simsek a,∗ , Didem Saloglu a , Nazlı Ozcan a , Ivan Novak b , Dusan Berek b a Chemical and Process Engineering Department, Yalova University, 77100 Yalova, Turkey b Polymer Institute, Slovak Academy of Sciences, 84541 Bratislava, Slovakia a r t i c l e i n f o Article history: Received 26 May 2016 Revised 20 October 2016 Accepted 8 November 2016 Available online xxx Keywords: Carbon fiber Chitosan Composite, Bisphenol-A Adsorption Kinetics a b s t r a c t Microporous carbon fibers (CFs) were in situ embedded in chitosan–polyvinyl alcohol (CHT-PVA) poly- mer matrix to produce an approximately 10 mm-thick carbon-polymer composite film (CHT-PVA/CF). The composite films were prepared with different CF:(CHT-PVA) ratios of 0.5–3.0 (w/w) and were used as novel adsorbents for the remediation of bisphenol A (BPA) from water. The composites were character- ized by SEM, TGA-DTG, FTIR and XPS analysis. When CF was introduced into the matrix of CHT-PVA, the BPA removal performance increased from 5.8% to 97.6%. The adsorption performances of CHT-PVA/CF composites were investigated with respect to solution pH, temperature and time. The optimal pH for maximum adsorption was found as 6.0. The Freundlich and Dubinin–Raduskevich isotherm models were fitted to the equilibrium data better than the Langmuir model. According to the kinetics results, the equi- librium time of CHT-PVA/CF composite film was found 2 h and the kinetic data were well described by the pseudo-second-order equation. After saturated adsorption, composite film can be easily regenerated and reused within five cycles. © 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. 1. Introduction Endocrine-disrupting chemicals (EDCs) have received consider- able social and scientific concern over the past decade as they can occupy the hormone receptors resulting a risk to human and an- imals [1,2]. Bisphenol-A (2, 2-bis(4-hydroxyphenyl)-propane, BPA) is used as an important industrial chemical for the production of polycarbonates, epoxy resins, and plastics [1]. BPA has been rec- ognized as a critical pollutant due to its weak estrogen-like effect and cannot be removed in the conventional wastewater treatment processes [3,4]. Regarding the adsorption technique, it is critical to apply effective adsorbents to decrease the concentration level of EDCs in the environment. Chitosan, second most abundant biopolymer next to cellulose [5], has many reactive amino and hydroxyl free functional groups cross-linked with covalent or ionic cross-linkers [6,7]. Although it is known as an excellent biosorbent due to its large number of amine groups, it can only be dissolved in acid solution with low pH bringing out great limitations to its practical applications ∗ Corresponding author. Fax: +90 226 815 5401. E-mail addresses: esrabilgin622@gmail.com, ebilgin.simsek@yalova.edu.tr (E. Bilgin Simsek). [5,8]. Therefore, different kinds of substances have been used to form composite with chitosan such as sepiolite [9], montmoril- lonite [10], carbon nanotube [11], graphene [12,13], polyvinyl al- cohol [14], polyvinyl chloride, kaolin [15], silver nanoparticles [16], halloysite nanotubes [17] and attapulgite [18]. Since polyvinyl al- cohol is a highly hydrophilic, biocompatible and nontoxic poly- mer, chitosan-PVA composites have been utilized as effective ad- sorbents for heavy metal and dye removal from aqueous solution [14,19,20]. Carbon based materials, such as carbon nanotubes, carbon fibers, activated carbon, and graphene oxide have emerged as promising nanofillers for polymer nanocomposites due to their chemical stability, large specific surface area, abundant pore size distribution, and feasibility of mass production [2]. Carbonaceous materials are ideal candidate matrices for chitosan for widespread applications in bone tissue engineering [21], hydrogen storage [22], adsorption [23], electrode [24,25] and sensor [26]. Carbon fibers (CFs) can be classified by differences in the orientation of graphitic layers relating to fiber axis: platelet, tubular, and herringbone [27]. Owing to their strong van der Waals attraction, CFs can agglom- erate easily which results in improper dispersion. The introducing CFs into the polymer chain can significantly improve the extent of dispersion of the fibers and meanwhile improve the electrical and mechanical properties of polymers [27]. http://dx.doi.org/10.1016/j.jtice.2016.11.008 1876-1070/© 2016 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Please cite this article as: E. Bilgin Simsek et al., Carbon fiber embedded chitosan/PVA composites for decontamination of endocrine dis- ruptor bisphenol-A from water, Journal of the Taiwan Institute of Chemical Engineers (2016), http://dx.doi.org/10.1016/j.jtice.2016.11.008