Ma Qingguo, Huo Pengcheng, Wang Kesong, Yuan Ye, Bai Songjiang, Zhao Chentong, Li Wenzhuo
Department of Chemistry and Chemical Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China.
Molecules. 2024 Aug 12;29(16):3822. doi: 10.3390/molecules29163822.
Formaldehyde (HCHO) is identified as the most toxic chemical among 45 organic compounds found in industrial wastewater, posing significant harm to both the environment and human health. In this study, a novel approach utilizing the Lanthanum-manganese complex oxide (LaMnO)/peroxymonosulfate (PMS) system was proposed for the effective removal of HCHO from wastewater. Perovskite-Type LaMnO was prepared by sol-gel method. The chemical compositions and morphology of LaMnO samples were analyzed through thermogravimetric analysis (TG), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). The effects of LaMnO dosage, PMS concentration, HCHO concentration, and initial pH on the HCHO removal rate were investigated. When the concentration of HCHO is less than 1.086 mg/mL (5 mL), the dosage of LaMnO is 0.06 g, and n(PMS)/n(HCHO) = 2.5, the removal rate of HCHO is more than 96% in the range of pH = 5-13 at 25 °C for 10 min. Compared with single-component MnO, the perovskite structure of LaMnO is beneficial to the catalytic degradation of HCHO by PMS. It is an efficient Fenton-like oxidation process for treating wastewater containing HCHO. The LaMnO promoted the formation of SO• and HO•, which sequentially oxidized HCHO to HCOOH and CO.
甲醛（HCHO）被确定为工业废水中发现的45种有机化合物中毒性最大的化学物质，对环境和人类健康都造成了重大危害。在本研究中，提出了一种利用镧锰复合氧化物（LaMnO）/过一硫酸盐（PMS）体系从废水中有效去除HCHO的新方法。采用溶胶-凝胶法制备了钙钛矿型LaMnO。通过热重分析（TG）、X射线衍射（XRD）、X射线光电子能谱（XPS）和透射电子显微镜（TEM）对LaMnO样品的化学成分和形貌进行了分析。研究了LaMnO用量、PMS浓度、HCHO浓度和初始pH值对HCHO去除率的影响。当HCHO浓度小于1.086 mg/mL（5 mL），LaMnO用量为0.06 g，n（PMS）/n（HCHO）=2.5时，在25℃下pH = 5-13范围内反应10 min，HCHO去除率超过96%。与单组分MnO相比，LaMnO的钙钛矿结构有利于PMS对HCHO的催化降解。这是一种处理含HCHO废水的高效类芬顿氧化工艺。LaMnO促进了SO•和HO•的形成，它们依次将HCHO氧化为HCOOH和CO。
