@article {DIAS2020121993,
	title = {Activation of co-pyrolysis chars from rice wastes to improve the removal of Cr3+ from simulated and real industrial wastewaters},
	journal = {Journal of Cleaner Production},
	volume = {267},
	year = {2020},
	note = {n/a},
	pages = {121993},
	abstract = {<p>Chromium is one of the most important raw materials for the European Union. Adsorption has become an important process for the recovery of metals from wastewaters, which has led to a demand for low-cost and eco-friendly adsorbents. The objective of this work was to use new and renewable carbon-based adsorbents from rice wastes in the removal/recovery of Cr(III) from synthetic and real wastewaters. Rice wastes were submitted to co-pyrolysis and the resulting char was optimized through physical and/or chemical activations/treatments. A commercial activated carbon was used for comparison purposes. All adsorbents were characterized (including an ecotoxicity test for the char precursor) and submitted to Cr(III) removal assays from a synthetic solution, in which two solid/liquid ratios (S/L) were tested (5 and 10~g/L). The CO2 activated carbon at a S/L~=~5~g/L was the biomass-derived adsorbent that performed better, obtaining a maximum Cr(III) uptake capacity of 9.23~mg/g comparable to the one obtained by the commercial adsorbent at the same S/L (9.80~mg/g). The good results on this biomass-derived carbon were due to the effective volatile matter removal during the activation (from 22.7 to 4.25\% w/w), which increased both surface area (from \&lt;5.0 to 325~m2/g) and ash content (from 30.0 to 40.4\% w/w), allowing an increase in Cr(III) removal due to ion exchange mechanism and porosity development. The best adsorbent, under optimized conditions, was also applied to a chromium rich industrial wastewater. The results obtained in this real case application demonstrated a competition effect due to the presence of other ions.</p>
},
	keywords = {activated carbons, Activation, Adsorption, Cr(III), Pyrolysis, Rice wastes},
	issn = {0959-6526},
	doi = {https://doi.org/10.1016/j.jclepro.2020.121993},
	url = {http://www.sciencedirect.com/science/article/pii/S0959652620320400},
	author = {Diogo Dias and Bernardo, Maria and Matos, In{\^e}s and Fonseca, Isabel and Filomena Pinto and Nuno Lapa}
}
