Chemical and Petroleum Engineering, University of Calgary, Calgary, Alberta, Canada.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2013;48(13):1649-54. doi: 10.1080/10934529.2013.815457.
In this study, various types of adsorbents were examined for the removal of Naphthenic acids (NAs) in the preliminary stage of this study. Among them, activated carbon and nickel (Ni) based alumina (Ni-Al2O3) possess relatively high adsorption capacity of NAs. The removal of NAs was evaluated comparing the total organic carbon (TOC) of the solution before and after the adsorption process. The effect of Ni loading was investigated using Ni-Al2O4 with various nickel loadings. The highest adsorption capacity (20 mg of TOC/1 mg of adsorbent) was belong to Ni-Al2O4 with 10.7% Ni loading. By the addition of salt (1500 ppm NaCl) to NAs solutions having concentrations from of 15 to 38 ppm, it was observed that the adsorption decreased dramatically (up to 80%) depending on the concentration of TOC. The kinetics of the adsorption of TOC on Ni-based alumina was also investigated. The decrease of TOC was more that 40% in the first half hour, indicating that adsorption was very rapid in the beginning. The adsorption increased slightly for up to 5 h and then leveled off when the TOC reached to 50% of initial TOC concentration. However, when sodium chloride (NaCl) was added to the solution, the adsorption decreased to almost 9% within the first half hour, reaching to almost 5% after 3 h. These phenomena suggest that the effectiveness of adsorbents may be improved by decreasing the total dissolved salts in tailings pond wastewater.
在本研究中，在初步阶段，研究了各种类型的吸附剂来去除环烷酸（NAs）。其中，活性炭和镍（Ni）基氧化铝（Ni-Al2O3）对 NAs 具有较高的吸附能力。通过比较吸附前后溶液的总有机碳（TOC）来评估 NAs 的去除效果。通过使用不同镍负载量的 Ni-Al2O4 考察了 Ni 负载量的影响。Ni 负载量为 10.7%的 Ni-Al2O4 的吸附容量最高（20mgTOC/1mg 吸附剂）。向浓度为 15-38ppm 的 NAs 溶液中添加盐（1500ppm NaCl），观察到吸附量根据 TOC 浓度显著下降（高达 80%）。还研究了 TOC 在 Ni 基氧化铝上吸附的动力学。在最初的半小时内，TOC 的减少量超过 40%，表明吸附在开始时非常迅速。吸附量在最初 5 小时内略有增加，然后当 TOC 达到初始 TOC 浓度的 50%时趋于平稳。然而，当向溶液中添加氯化钠（NaCl）时，在前半小时内吸附量下降到几乎 9%，3 小时后几乎达到 5%。这些现象表明，通过降低尾矿库废水中的总溶解盐含量，可以提高吸附剂的有效性。
