Chen Shaohua, Sun Yan, Li Jia, Xiong Ling
Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074, China E-mail:
Water Sci Technol. 2017 Dec;76(11-12):3404-3409. doi: 10.2166/wst.2017.503.
Amyl xanthate (AX), a widely used reagent in sulfide mineral flotation, has caused serious environmental problems. Manganese dioxides (MnO), ubiquitous in natural soils and sediments, are one kind of important oxidant or catalyst in facilitating organic pollutant decomposition. In this study, the oxidative degradation of AX by MnO was investigated in batch experiments. It was found that up to 90% AX was decomposed by MnO in 30 min and the removal efficiency of AX depended strongly on the loading of MnO and pH value in the solution where the reactions closely followed a pseudo-first-order model. The reaction orders with respect to the initial AX concentration, MnO concentration and pH value were 0.4573, 0.2034, and -0.1701, respectively. Coexisting metal ions, such as Mn, Fe, Ca and Mg, displayed suppressive effects and the inhibitive capacity of the metal ions followed the order Mn > Fe > Ca > Mg. However, the effect of humic acid (HA) on reaction rates was significant only at higher concentrations. This study provided meaningful information to elucidate the oxidative degradation of AX by MnO
戊基黄药（AX）是硫化矿浮选过程中广泛使用的一种试剂，它已引发了严重的环境问题。二氧化锰（MnO）在天然土壤和沉积物中普遍存在，是促进有机污染物分解的一类重要氧化剂或催化剂。在本研究中，通过批次实验研究了MnO对AX的氧化降解作用。结果发现，在30分钟内，高达90%的AX被MnO分解，AX的去除效率强烈依赖于MnO的负载量以及溶液的pH值，反应过程严格遵循准一级模型。AX初始浓度、MnO浓度和pH值的反应级数分别为0.4573、0.2034和-0.1701。共存金属离子，如Mn、Fe、Ca和Mg，表现出抑制作用，金属离子的抑制能力顺序为Mn＞Fe＞Ca＞Mg。然而，腐殖酸（HA）仅在较高浓度时对反应速率有显著影响。本研究为阐明MnO对AX的氧化降解提供了有意义的信息。
