Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
Department of Environmental Health Engineering, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
J Environ Manage. 2018 Mar 15;210:131-138. doi: 10.1016/j.jenvman.2018.01.004. Epub 2018 Jan 13.
The present study evaluates the efficacy of S-doped MgO (S-MgO) as compared with the plain MgO as a catalyst for destructive removal of tetracycline (TTC) in aqueous solutions. The S-MgO had around 6% S in its structure. Doping MgO with S caused increase in surface oxygen vacancy defects. Adding S-MgO (12 g/L) to a TTC aqueous solution (50 mg/L) caused removal of around 99% TTC at the neutral pH (ca. 5.1) and a short reaction time of 10 min. In comparison, plain MgO could remove only around 15% of TTC under similar experimental conditions. Diffusing O into the TTC solution under the reaction with S-MgO resulted in a considerable improvement of TTC removal as compared to diffusing N. Complete removal of TTC and 86.4% removal of its TOC could be obtained using 2 g/L S-MgO nanoparticles. The removal of TTC increased with the increase in solution temperature. The presence of nitrate, sulfate and chloride did not considerably affect the removal of TTC using S-MgO while TTC removal significantly decreased at the presence of bicarbonate and phosphate. The S-MgO was a stable and reusable catalyst exhibiting much higher catalytic activity than plain MgO for the TTC destruction. Accordingly, S-MgO is an emerging and efficient catalyst for catalytic decomposition and mineralization of such pharmaceutical compounds as TTC under atmospheric temperature and pressure.
本研究评估了 S 掺杂氧化镁（S-MgO）作为催化剂用于破坏水溶液中四环素（TTC）的效果，与普通氧化镁（MgO）相比。S-MgO 的结构中约有 6%的 S。S 掺杂 MgO 会导致表面氧空位缺陷增加。在 pH 值约为 5.1 的中性条件下，将 12 g/L 的 S-MgO 添加到 50 mg/L 的 TTC 水溶液中，10 分钟内可去除约 99%的 TTC；相比之下，在类似的实验条件下，普通 MgO 只能去除约 15%的 TTC。与扩散 N 相比，S-MgO 与 TTC 溶液反应时将 O 扩散到溶液中可显著提高 TTC 的去除率。使用 2 g/L 的 S-MgO 纳米颗粒可完全去除 TTC 和 86.4%的 TOC。TTC 的去除率随溶液温度的升高而增加。硝酸盐、硫酸盐和氯化物的存在对使用 S-MgO 去除 TTC 的影响不大，而碳酸氢盐和磷酸盐的存在会显著降低 TTC 的去除率。S-MgO 是一种稳定且可重复使用的催化剂，其对 TTC 的破坏的催化活性明显高于普通 MgO。因此，S-MgO 是一种新兴的、高效的催化剂，可在大气温度和压力下催化分解和矿化 TTC 等药物化合物。
