Dipartimento di Ingegneria Chimica, Università di Napoli Federico II, P.le Tecchio, 80-80125 Napoli, Italy.
J Hazard Mater. 2013 Sep 15;260:451-8. doi: 10.1016/j.jhazmat.2013.05.055. Epub 2013 Jun 6.
This work aims to the analysis of arsenic desorption from an exhaust activated carbon used for the purification of a natural water. This last was used to mimic the properties of common groundwater or drinking water. Different low-cost and harmless eluting solutions were considered, including distilled water, natural water, saline (NaCl, CaCl₂ and NaNO₃) and basic (NaOH) solutions. Experimental results showed that, for 1g of activated carbon with arsenic loading close to the maximum value available for the model natural water (ω ≈ 0.1 mg/g), it is possible to recover more than 80% of the arsenic using 20 ml of 0.1 M sodium chloride solution. A temperature variation within 20 and 40 °C has scarce effect on desorption efficiency. A comparison between desorption data and adsorption isotherms data suggests that arsenic adsorption is actually a reversible process. Therefore, it is virtually possible to increase arsenic recovery efficiency close to 100% by increasing the NaCl concentration or the volume of the desorption solution, but a preliminary cost benefit analysis lead to consider a NaCl 0.1M solution as an optimal solution for practical applications.
本工作旨在分析一种用于净化天然水的废气活性炭中砷的解吸。该天然水用于模拟常见地下水或饮用水的性质。考虑了不同的低成本、无害洗脱液，包括蒸馏水、天然水、盐水（NaCl、CaCl₂ 和 NaNO₃）和碱性溶液（NaOH）。实验结果表明，对于砷负载量接近模型天然水最大可用值（ω≈0.1mg/g）的 1g 活性炭，使用 20ml 0.1M 氯化钠溶液可以回收超过 80%的砷。在 20 至 40°C 范围内的温度变化对解吸效率影响不大。解吸数据与吸附等温线数据的比较表明，砷吸附实际上是一个可逆过程。因此，通过增加氯化钠浓度或洗脱液体积，几乎可以将砷的回收效率提高到接近 100%，但初步的成本效益分析表明，0.1M 氯化钠溶液是实际应用的最佳溶液。
