Use of lignin generated in the bioethanol production process for biosorption of lead ions in aqueous solution
International Journal of Development Research
Use of lignin generated in the bioethanol production process for biosorption of lead ions in aqueous solution
Received 08th December, 2019; Received in revised form 24th January, 2020; Accepted 04th February, 2020; Published online 31st March, 2020
Copyright © 2020, Isamara Godoi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Lignin contained in the black liquor generated during alkaline delignification of cellulose for bioethanol production was precipitated with H2SO4 and evaluated as biosorbent of Pb(II) ions in aqueous solution. Experimental design (DOE) and response surface methodology (RSM) were carried out in order to reduce the number of experiments and achieve the best conditions for biosorption procedure. Three factors at three levels were studied: initial pH (3; 4 and 5), biosorbent mass (50 mg; 100 mg and 150 mg), and initial Pb(II) concentration (40 mg L-1; 60 mg L-1 and 80 mg L-1). The kinetic parameters were also evaluated using the biosorption measurements. The results indicated that the higher the metal concentration, the lower was the required amount of biosorbent in Pb(II) removal. Pb(II) amount adsorbed by lignin was 60.4 mg g-1 and corresponded to its 75.5% removal. The kinetic model that best fit was the pseudo-second order.
