Zhang Lan-He, Gao Wei-Wei, Chen Zi-Cheng, Zhang Hai-Feng, Wang Xu-Ming
School of Chemical Engineering, Northeast Electric Power University, Jilin 132012, China.
Beijing Agro-Biotechnology Research Center, Beijing 100089, China.
Huan Jing Ke Xue. 2018 Jul 8;39(7):3194-3202. doi: 10.13227/j.hjkx.201711052.
In order to improve the activity and working life of metal catalysts in the heterogeneous catalytic ozonation of organic wastewater, four kinds of Mn-Co/ceramic honeycomb (CH) catalysts with different mass ratios of Mn and Co were prepared by coating method using cobalt nitrate hexahydrate [Co(NO)·6HO] and manganese nitrate [Mn(NO)] as precursors, respectively, and CH as the carrier. The structure of the catalysts was analyzed via X-ray diffraction (XRD), N adsorption/desorption, field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). The mechanical properties of the catalysts were studied. The reaction kinetics model of O alone and catalytic ozonation of the hydroquinone were established and catalytic ozonation performance of catalysts was investigated. The results showed that the crystal phase of MnCo/CH belonged to CoAlO and that the crystal phase of the Mn-Co/CH catalyst (MnCo, MnCo, and MnCo) mainly belonged to MnO and CoO. In particular, the MnCo/CH catalyst had a large specific surface area of 190 m·g, high pore volume of 0.25 cm·g, and pore size of 4.8 nm. The highest catalytic activity was obtained when Mn∶Co was 1∶1 (MnCo/CH catalyst). The catalytic activity of the MnCo/CH catalyst was the highest, and removal efficiencies of hydroquinone and COD were 78% and 54%, respectively, using MnCo/CH catalytic ozonation. The Mn-Co/CH catalyst had a high compressive strength (15.89-16.94 MPa). The degradation efficiency of hydroquinone decreased significantly after the addition of tert-butanol, which indicated that·OH played an important role in the MnCo/CH catalytic ozonation. The catalytic ozonation process fitted the first-order kinetic model. The apparent rate constant for O alone was only 0.0306. Furthermore, the MnCo/CH catalyst had the highest rate, with an apparent rate constant of 0.0535 min. The Mn-Co/CH catalyst was easy to industrialize owing to its lower consumption, excellent catalytic characteristics, and long working life.
为提高金属催化剂在有机废水非均相催化臭氧化中的活性和使用寿命，分别以六水合硝酸钴[Co(NO)·6HO]和硝酸锰[Mn(NO)]为前驱体，以陶瓷蜂窝（CH）为载体，采用涂覆法制备了4种不同锰钴质量比的Mn-Co/陶瓷蜂窝（CH）催化剂。通过X射线衍射（XRD）、N吸附/脱附、场发射扫描电子显微镜（FESEM）和X射线光电子能谱（XPS）对催化剂结构进行了分析。研究了催化剂的机械性能。建立了单独臭氧和对苯二酚催化臭氧化的反应动力学模型，并考察了催化剂的催化臭氧化性能。结果表明，MnCo/CH的晶相属于CoAlO，Mn-Co/CH催化剂（MnCo、MnCo和MnCo）的晶相主要属于MnO和CoO。特别是，MnCo/CH催化剂具有190 m·g的大比表面积、0.25 cm·g的高孔容和4.8 nm的孔径。当Mn∶Co为1∶1时（MnCo/CH催化剂），催化活性最高。MnCo/CH催化臭氧化时，MnCo/CH催化剂的催化活性最高，对苯二酚和COD的去除率分别为78%和54%。Mn-Co/CH催化剂具有较高的抗压强度（15.89-16.94 MPa）。加入叔丁醇后，对苯二酚的降解效率显著降低，表明·OH在MnCo/CH催化臭氧化中起重要作用。催化臭氧化过程符合一级动力学模型。单独臭氧的表观速率常数仅为0.0306。此外，MnCo/CH催化剂的速率最高，表观速率常数为0.0535 min。Mn-Co/CH催化剂消耗较低、催化特性优异且使用寿命长，易于工业化应用。
