School of Energy & Environment Engineering, Zhongyuan University of Technology, Zhengzhou 451191, China.
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
Molecules. 2022 Aug 5;27(15):4973. doi: 10.3390/molecules27154973.
Iron-manganese silicate (IMS) was synthesized by chemical coprecipitation and used as a catalyst for ozonating acrylic acid (AA) in semicontinuous flow mode. The Fe-O-Mn bond, Fe-Si, and Mn-Si binary oxide were formed in IMS on the basis of the results of XRD, FTIR, and XPS analysis. The removal efficiency of AA was highest in the IMS catalytic ozonation processes (98.9% in 15 min) compared with ozonation alone (62.7%), iron silicate (IS) catalytic ozonation (95.6%), and manganese silicate catalytic ozonation (94.8%). Meanwhile, the removal efficiencies of total organic carbon (TOC) were also improved in the IMS catalytic ozonation processes. The IMS showed high stability and ozone utilization. Additionally, HO was formed in the process of IMS catalytic ozonation. Electron paramagnetic resonance (EPR) analysis and radical scavenger experiments confirmed that hydroxyl radicals (•OH) were the dominant oxidants. Cl, HCO, PO, Ca, and Mg in aqueous solution could adversely affect AA degradation. In the IMS catalytic ozonation of AA, the surface hydroxyl groups and Lewis acid sites played an important role.
采用化学共沉淀法合成了铁锰硅酸盐（IMS），并将其用作半连续流动模式下臭氧氧化丙烯酸（AA）的催化剂。基于 XRD、FTIR 和 XPS 分析的结果，在 IMS 中形成了 Fe-O-Mn 键、Fe-Si 和 Mn-Si 二元氧化物。与单独臭氧氧化（62.7%）、硅酸铁（IS）催化臭氧氧化（95.6%）和硅酸锰催化臭氧氧化（94.8%）相比，IMS 催化臭氧氧化过程中 AA 的去除效率最高（15 分钟内达到 98.9%）。同时，IMS 催化臭氧氧化过程中总有机碳（TOC）的去除效率也得到了提高。IMS 表现出高稳定性和臭氧利用率。此外，在 IMS 催化臭氧氧化过程中形成了 HO。电子顺磁共振（EPR）分析和自由基清除剂实验证实，羟基自由基（•OH）是主要的氧化剂。水溶液中的 Cl、HCO、PO、Ca 和 Mg 会对 AA 的降解产生不利影响。在 IMS 催化臭氧氧化 AA 的过程中，表面羟基和路易斯酸位起着重要作用。
