Enhanced Zn(II) and Pb(II) removal from wastewater using thiolated chitosan beads (ETB); [Peningkatan jerapan Zn(II) dan Pb(II) daripada sisa air dengan manik kitosan tertiol]

• Published in: Malaysian Journal of Analytical Sciences
• Main Author: Yong S.K.; Bolan N.; Lombi E.; Skinner W.
• Format: Article
• Language: English
• Published: Malaysian Society of Analytical Sciences 2015
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84932100719&partnerID=40&md5=7ad5b32d4893d7d8a625fa3166644d5d

Chitosan beads (E) was first prepared by phase inversion of chitosan acetate solutions. Thiolated chitosan beads (ETB) was synthesised by soaking E in a mixture of ethanol and carbon disulfide for 7 days and then rinsed thoroughly with water and ethanol. Sulfur content of ETB is 7.88 %. The thiolation process has increased the Brunauer-Emmett-Teller (BET) surface area of E beads from 39.5 m2/g to 46.3 m2 /g. ETB is categorised as macroporous material (pore aperture: 182 nm) with multiple and uniform porous layers. A new shoulder at 1594 cm -1 was found in Fourier Transform infrared spectroscopy (FTIR) spectra of ETB, is assigned to thiourea moiety and was confirmed by X-ray photoelectron spectroscopy (XPS) spectra. The Pb(II) sorption capacity by ETB was higher than E beads at all sorbent dosage (except 5.0 g/L). At sorbent dosage of 5.0 g/L, sorption capacity of Zn(II) by ETB was enhanced by 3.2 times as compared to E beads. Sorption data fitted well to linearised Freundlich isotherm model and Ho’s pseudo second order kinetic model. The higher KF value of ETB than E indicated greater sorption capacity. The increase in Zn(II) and Pb(II) sorption capacities were attributed to enhanced chemisorption with thiol group in ETB beads. © 2015, Malaysian Society of Analytical Sciences. All rights reserved.