College of Chemistry and Chemical Engineering, Dezhou University, Dezhou 253023, China.
Chemosphere. 2018 Jan;190:97-102. doi: 10.1016/j.chemosphere.2017.09.141. Epub 2017 Sep 28.
To exploit the adsorption capacity of commercial powdered activated carbon (PAC) and to improve the efficiency of Cr(VI) removal from aqueous solutions, the adsorption of Cr(VI) by commercial PAC and the countercurrent two-stage adsorption (CTA) process was investigated. Different adsorption kinetics models and isotherms were compared, and the pseudo-second-order model and the Langmuir and Freundlich models fit the experimental data well. The Cr(VI) removal efficiency was >80% and was improved by 37% through the CTA process compared with the conventional single-stage adsorption process when the initial Cr(VI) concentration was 50 mg/L with a PAC dose of 1.250 g/L and a pH of 3. A calculation method for calculating the effluent Cr(VI) concentration and the PAC dose was developed for the CTA process, and the validity of the method was confirmed by a deviation of <5%.
为了利用商业粉末状活性炭 (PAC) 的吸附能力并提高从水溶液中去除六价铬 (Cr(VI)) 的效率，研究了商业 PAC 对 Cr(VI)的吸附作用和逆流两段吸附 (CTA) 工艺。比较了不同的吸附动力学模型和等温线，准二级模型和 Langmuir 及 Freundlich 模型均能很好地拟合实验数据。与传统的单级吸附工艺相比，当初始 Cr(VI)浓度为 50mg/L、PAC 剂量为 1.250g/L、pH 值为 3 时，CTA 工艺可将 Cr(VI)去除效率提高 37%，达到 >80%。为 CTA 工艺开发了一种计算流出液 Cr(VI)浓度和 PAC 剂量的计算方法，通过偏差 <5%验证了该方法的有效性。
