Abstract
The growing textile industry produces large volumes of hazardous wastewater containing dyes, which stresses the need for cheap, efficient adsorbing technologies. This study investigates a novel preprocessing method for producing activated carbons from abundantly available softwood bark. The preprocessing involved a continuous steam explosion preconditioning step, chemical activation with ZnCl 2, pyrolysis at 600 and 800 °C, and washing. The activated carbons were subsequently characterized by SEM, XPS, Raman and FTIR prior to evaluation for their effectiveness in adsorbing reactive orange 16 and two synthetic dyehouse effluents. Results showed that the steam-exploded carbon, pyrolyzed at 600 °C, obtained the highest BET specific surface area (1308 m 2/g), the best Langmuir maximum adsorption of reactive orange 16 (218 mg g −1) and synthetic dyehouse effluents (>70 % removal) of the tested carbons. Finally, steam explosion preconditioning could open up new and potentially more sustainable process routes for producing functionalized active carbons.
| Original language | English |
|---|---|
| Article number | 130698 |
| Journal | Bioresource Technology |
| Volume | 400 |
| Publication status | Published - May 2024 |
| MoE publication type | A1 Journal article-refereed |
Funding
This work was supported by Vinnova (Swedish Governmental Agency for Innovation Systems), grant number 2017\u201305408, Bio4Energy, a strategic research environment appointed by the Swedish government, and Valmet AB. We thank Gunnar Kal\u00E9n at the Biomass Technology Center, Ume\u00E5, Sweden, and Jan Detlefsen at Valmet Fiber Technology Center, Sundsvall, Sweden, for operational work during the preprocessing of biomass and steam explosion runs, respectively. Furthermore, Tao Hu and Rafal Sliz at Oulu University, Research Unit of Sustainable Chemistry, are acknowledged for their skilful performance of FTIR and XPS measurements. In addition, Ume\u00E5 University Vibrational Spectroscopy Core Facility, Ume\u00E5, Sweden, is acknowledged for granting access to a suitable Raman instrument.