| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 588143 | Process Safety and Environmental Protection | 2016 | 11 Pages |
•Grapefruit peeling is a good biosorbent for the removal of leather dyes and Cr(VI).•H2O2 pretreatment of grapefruit peeling enhanced its adsorption properties.•Homogeneous Surface Diffusion Model can be used for prediction of breakthrough curves.
The objective of this study was to find a suitable and versatile agroforestry waste as alternative low-cost biosorbents for the removal of inorganic and organic compounds present in the wastewater of tannery industry [leather dyes and Cr(VI)]. Grapefruit peelings, fern, eucalyptus barks, oak leaves and cane pruning of grapevines were evaluated as biosorbents. Among them, grapefruit peelings showed the best results reaching 45 and 55% for the mixture of dyes and Cr(VI), respectively. A significant improvement in the performance of this biosorbent was obtained when it was pretreated with H2O2 (1 M) attaining the highest removal capacity of 80% and 100%, respectively. This biosorbent was characterised showing an adsorption capacity of 1.1003 meq/g and pHZPC 3.48. The adsorption working parameters, kinetics and isotherms were deeply studied in order to scale up the process to a continuous treatment system. Adsorption isotherms data fitted well to the Langmuir model with a maximum uptake of 37.427 mg/g for dyes mixture and 39.0628 mg/g for Cr(VI). Finally, the dynamic behaviour of the system, operating at different flow rates, was evaluated using a Homogeneous Surface Diffusion Model. Pretreated grapefruit peelings demonstrated to be a suitable low-cost biosorbent in the treatment of wastewater of tannery industry.
