Title
Kinetic study of lead(II) removal from aqueous solution onto lignin-based materials
Authors
DUMITRU BULGARIU GABRIELA NACU (RUSU) TEODOR MALUTAN and LAURA BULGARIU

Received March 22, 2014
Published Volume 50 Issue 2 February
Keywords lignin-based materials, lead(II) ions, biosorption, kinetics, aqueous solution

Abstract
In this study, the removal of lead(II) ions from aqueous solution on two types of lignin-based materials (a cellolignin obtained from chestnut wood (L1) and lignin extracted from rape (L2)) was examined from a kinetic point of view. The influence of initial lead(II) concentration and contact time was studied in batch experiments. The experimental data showed that biosorbent L2 had a higher biosorption capacity than L1, and required a shorter contact time. The kinetics of biosorption was followed based on the amount of lead(II) retained at various time intervals, and the data were analyzed using three kinetic models: pseudo-first order, pseudo-second order and intra-particle diffusion model. The results indicated that chemical interaction might to be a rate-limiting process in lead(II) removal on both biosorbents. This hypothesis was sustained by the analysis of FT-IR spectra, which showed that biosorbent L2 had more alcoholic OH groups than L1, and they played an important role in the biosorption process.