Cr(VI) adsorption from electroplating plating wastewater by chemically modified coir pith

Simple item page
dc.contributor.authorParinda Suksabye
dc.contributor.authorPaitip Thiravetyan
dc.contributor.correspondenceP. Thiravetyan; Division of Biotechnology, School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok 10150, Thailand; email: paitip.thi@kmutt.ac.th
dc.date.accessioned2025-03-10T07:37:40Z
dc.date.available2025-03-10T07:37:40Z
dc.date.issued2012
dc.description.abstractCoir pith samples were chemically modified by grafting with acrylic acid for the removal of Cr(VI) from electroplating wastewater. The presence of acrylic acid on the coir pith surface was verified by a scanning electron microscope with an electron dispersive x-ray spectrometer (SEM/EDX), Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG). The carbonyl groups (CO) from the carboxylic acids (COOH) increased on the coir pith surface after grafting with acrylic acid. In addition, the thermal stability of the acrylic acid-grafted coir pith also improved. The optimum conditions for grafting the acrylic acid on the coir pith consisted of 2 M acrylic acid and 0.00125 M ceric ammonium nitrate (CAN, as an initiator). The maximum Cr(VI) removal (99.99 ± 0.07%) was obtained with the following conditions: a 1.3% (w/v) dosage of acrylic acid-grafted coir pith, a system pH of 2, a contact time of 22 h, a temperature of 30 ¡C, a particle size of <150 _m and an initial Cr(VI) of 1,171 mg l-1. At system pH of 2, Cr(VI) in the HCrO4- form can be adsorbed with acrylic acid-grafted coir pith via an electrostatic attraction. The adsorption isotherm of 2 M acrylic acid-grafted coir pith exhibited a good fit with the Langmuir isotherm. The maximum Cr(VI) adsorption capacity of the 2 M acrylic acid-grafted coir pith was 196.00 mg Cr(VI) g-1 adsorbent, whereas for coir pith without grafting, the maximum Cr(VI) removal was 165.00 mg Cr(VI) g-1 adsorbent. The adsorption capacity of the acrylic acid-grafted coir pith for Cr(VI) was higher compared to the original coir pith. This result was due to the enhancement of the carbonyl groups on the coir pith surface that may have involved the mechanism of chromium adsorption. The X-ray absorption near edged structure (XANES) and desorption studies suggested that most of the Cr(III) that presented on the acrylic acid-grafted coir pith was due to the Cr(VI) being reduced to Cr(III) on the adsorbent surface. FTIR confirmed the involvement of the carbonyl groups (CO) and the methoxy groups (OCH3) in the mechanism of chromium adsorption. Thermodynamic study, such as enthalpy (_H), free energy (_G) and entropy change (_S) indicated that the overall adsorption process was endothermic, spontaneous and randomness. In addition, the adsorption process was favored at high temperatures. © 2012 Elsevier Ltd.
dc.identifier.citationJournal of Environmental Management
dc.identifier.doi10.1016/j.jenvman.2011.10.020
dc.identifier.issn3014797
dc.identifier.scopus2-s2.0-84858738831
dc.identifier.urihttps://repository.dusit.ac.th//handle/123456789/5001
dc.languageEnglish
dc.publisherAcademic Press
dc.rights.holderScopus
dc.subjectAcrylic acid
dc.subjectAdsorption
dc.subjectCoir pith
dc.subjectCr(VI)
dc.subjectGrafting
dc.titleCr(VI) adsorption from electroplating plating wastewater by chemically modified coir pith
dc.typeArticle
mods.location.urlhttps://www.scopus.com/inward/record.uri?eid=2-s2.0-84858738831&doi=10.1016%2fj.jenvman.2011.10.020&partnerID=40&md5=972b2e2ff48da119ec8551b0b713b002
oaire.citation.endPage8
oaire.citation.startPage1
oaire.citation.volume102
Files
Collections
SCOPUS 2010-2014