Shi Qi, Long Ding, Long Hong-Ming, Chun Tie-Jun
School of Metallurgical Engineering, Anhui University of Technology, Maanshan 243002, China.
Anhui Province Key Laboratory of Metallurgy Engineering & Resources Recycling; Anhui University of Technology, Maanshan 243002, China.
Materials (Basel). 2019 Dec 26;13(1):125. doi: 10.3390/ma13010125.
Ce-V-Ti and Ce-V-Ti/GO catalysts synthesized by the sol-gel method were used for the catalytic combustion of dioxins at a low temperature under simulating sintering flue gas in this paper. The catalytic mechanism of Ce-V-Ti catalysts modified with graphene oxides (GO) at a low temperature was revealed through X-ray diffractometer (XRD), Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), H-temperature-programmed reduction (H-TPR) and Fourier transform infrared (FTIR). During the tests, chlorobenzene (CB) was used as a model reagent since the dioxins are poisonous. The results showed that introducing GO to Ce-V-Ti catalysts can improve the specific surface area and promote the CB adsorption on the surface of catalysts. Simultaneously, the Ce-V-Ti with 0.7 wt % GO support showed the high activity with the conversion of 60% at 100 °C and 80% at 150 °C. The adsorb ability of catalysts is strengthened by the electron interaction between GO and CB through π-π bond. In the case of Ce-V-Ti catalysts, Ce played a major catalytic role and V acted as a co-catalytic composition. After GO modification, the concentration of Ce and V were enlarged. The synergy between Ce and V played the critical role on the low-temperature performance of catalysts under sintering flue gas.
本文采用溶胶-凝胶法合成的Ce-V-Ti和Ce-V-Ti/GO催化剂，在模拟烧结烟气条件下用于低温催化燃烧二噁英。通过X射线衍射仪（XRD）、布鲁诺尔-埃米特-泰勒（BET）法、透射电子显微镜（TEM）、X射线光电子能谱（XPS）、氢气程序升温还原（H-TPR）和傅里叶变换红外光谱（FTIR）揭示了氧化石墨烯（GO）改性的Ce-V-Ti催化剂的低温催化机理。试验过程中，由于二噁英有毒，采用氯苯（CB）作为模型试剂。结果表明，向Ce-V-Ti催化剂中引入GO可提高比表面积，促进CB在催化剂表面的吸附。同时，负载0.7 wt% GO的Ce-V-Ti催化剂表现出较高的活性，在100℃时转化率为60%，在150℃时转化率为80%。GO与CB之间通过π-π键的电子相互作用增强了催化剂的吸附能力。对于Ce-V-Ti催化剂，Ce起主要催化作用，V起助催化作用。GO改性后，Ce和V的浓度增加。Ce和V之间的协同作用对烧结烟气条件下催化剂的低温性能起关键作用。
