Abstract Sources of fluoride contaminated water are found around the world and their treatment is required before human consumption. This paper contributes to advances in the use of bone-char as an adsorbent for fluoride, associating steps of chemical regeneration and fluoride adsorption in continuous systems, thereby making feasible the multiple use of the adsorbent. Following the development of low cost treatment of water defluoridation in a fixed bed column, using bone-char, regeneration was carried out with NaOH (0.5 mol/L) solution in subsequent adsorption/desorption cycles. The continuous system was modeled applying Thomas, Yoon-Nelson, Adams-Bohart, Wolborska and Yan models, and the Yan model showed the best adjustment. The adsorption capacity of 6.28 mg/g was obtained from the breakthrough curve. Chemical regeneration of bone-char was feasible, and a reduction in adsorption capacity of 30% was observed only after five adsorption/desorption cycles.

In various industrial processes, such as the process of obtaining potassium by solution mining or in the oil industry, fuels are burnt concurrently to the formation of saline effluents. The opportunity to sequester carbon through capturing the CO2 from the flue gas by carbonation of these effluents and reducing the potential of scaling of the water is evident. The use of saline industrial effluent from electrodialysis for carbon sequestration by mineralization of carbon dioxide is the focus of this work. The carbonation reaction of saline effluent of reverse electrodialysis, of low ionic strength and higher CO2 solubility, was simulated through OLI®. Precipitation tests were performed by bubbling 10-20 NL h-1 CO2 in a glass reactor containing the brine and pH adjusted to 8.9. The solid was characterized and the results from the simulation and the experiments were compared. The removal of calcium and strontium in the form of carbonates reach out up to 98% and 75%. The simulation results were in line with the experimental results for the calcium behavior, but not for strontium. The OLI® simulation was powerful to represent the calcium carbonate formation, however, comparisons between predicted Sr removal and testwork results presented differences and must be investigated.