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| 1 | M/ZSM-5(M=Cu、Mn、Fe、Ce、Ti)催化氧化甲苯性能研究显示文摘以ZSM-5分子筛为载体,采用浸渍法负载Cu、Mn、Fe、Ce、Ti制备一系列金属氧化物催化剂,利用SEM、XRD、N2吸附-脱附、XPS、H_(2)-TPR对催化剂的理化性质进行了表征,并考察了催化剂的催化氧化甲苯性能。结果表明,Cu/ZSM-5表面粗糙,金属元素分布均匀,具有较好的孔径结构、良好的低温还原性和丰富的吸附氧物种,且负载量为5%的Cu/ZSM-5表现出优异的甲苯催化活性和最佳的抗硫性,在SO_(2)环境下t90为224℃(GHSV=24000 h^(−1))。原位红外测试结果表明,甲苯的降解遵循以下途径,甲苯首先被吸附在催化剂表面形成吸附态甲苯,随后在催化剂作用下依次被转化为苯甲醛和苯甲酸,再经过开环反应形成马来酸、羧酸等小分子有机物,最终被氧化为CO_(2)和H_(2)O。 | 彭新宇 刘丽君 沈伯雄 边瑶 苏立超 | 2023 | 燃料化学学报(中英文)2023，51，6： | 3 |
| 2 | 稀土尾矿基整体催化剂的制备及其低浓度甲烷催化燃烧性能显示文摘以稀土尾矿泡沫陶瓷(Tailings foam ceramics,简称TFC)为载体,采用拟薄水铝石制备铝溶胶,经过泡沫陶瓷载体表面涂覆铝溶胶和Cu溶液浸渍得到CuO/γ-Al_(2)O_(3)/TFC整体式催化剂,并利用SEM,XRD,XPS,H_(2)-TPR等技术对催化剂进行表征,评价其甲烷催化燃烧反应性能。结果表明,与原泡沫陶瓷相比,负载CuO的样品催化活性明显增强;随着CuO的负载量增加,催化性能呈现先升高后降低的趋势,CuO的负载量达到4%时催化活性最佳,甲烷转化率为10%和90%时的反应温度分别为301和581℃。CuO的负载量达到6%时,催化剂的活性中心由分散态CuO转变为晶相CuO,导致CuO在载体表面分散度降低并且利用率下降,催化活性降低。负载到泡沫陶瓷载体上的CuO形貌呈球形,整体催化剂活性组分中所有催化剂铈以Ce^(3+),Ce^(4+)形态共存,铜以Cu2+和Cu+形态共存,各金属元素间变价表明催化剂有较高的氧化还原能力,催化剂表面发生反应:Cu^(2+)+Ce^(3+)→Cu^(+)+Ce^(4+)。 | 赵然 王莹 安想 赵增武 庞然 刘中兴 | 2022 | 中国稀土学报2022，40，3： | 2 |
| 3 | 氧化铈基催化剂在气相挥发性有机物降解领域的研究进展显示文摘挥发性有机化合物(VOCs)作为大气污染物的主要来源日益受到关注。催化氧化技术被认为是最有效的VOCs降解方法之一,其核心是催化剂。氧化铈(CeO2)基催化剂因具有良好的储氧和释氧能力、价格相对低廉而备受关注。本文在论述CeO2基催化剂降解VOCs机理的基础上,分别从单一CeO2和CeO2基复合金属或金属氧化物两个方面总结了近年来氧化铈基催化剂在光(热)催化氧化VOCs领域的研究进展。指出,增加负载材料的多样性、探究反应机理的本质、开发催化效果好且成本效益高的催化剂产品是该领域未来的研发趋势。 | 万莲 陈丰 | 2021 | 化工环保2021，41，3： | 2 |
| 4 | Active oxygen species and oxidation mechanism over Ce-doped LaMn_(0.8)Ni_(0.2)O_(3)/hierarchical ZSM-5 in pentanal oxidation显示文摘Hierarchical ZSM-5(HZ)molecular sieves based on fly ash were synthesized using a method combining water heat treatment with step-by-step calcination.The coupling catalysts between La_(1-x)Ce_(x)Mn_(0.8)-Ni_(0.2)O_(3)(x≤0.5)perovskites and HZ were prepared through the impregnation method,which were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),high-resolution transmission electron microscopy(HRTEM),N_(2)adsorption,X-ray photoelectron spectroscopy(XPS),NH3-temperature programmed desoprtion(NH3-TPD),H_(2)-temperature programmed reduction(H_(2)-TPR)and O_(2)-TPD techniques and investigated regarding pentanal oxidation at 120-390℃to explore the effects of Ce doping on the catalytic activity and the active oxygen species of the coupling catalysts,meanwhile,the reaction mechanism and pathway of pentanal oxidation were also studied.The results reveal that Ce substitution at La sites can change the electronic interactions between all the elements and promote the electronic transfer among La,Ce,Ni,Mn and HZ,influencing directly the physicochemical characteristics of the catalysts.Moreover,the amount and transfer ability of surface adsorbed oxygen(O_(2)-and O-)regarded as the reactive oxygen species and the low temperature reducibility are the main influence factors in pentanal oxidation.Additionally,La_(0.8)Ce_(0.2)Mn_(0.8)Ni_(0.2)O_(3)/HZ exhibits the best catalytic activity and deep oxidation capacity as well as a better water resistance due to its larger amount of surface adsorbed oxygen species and higher low temperature reducibility.What’s more,appropriate Ce substitution can significantly enhance the amount of O_(2)-ions,which can distinctly enhance the catalytic activity of the catalyst,and moderate acid strength and appropriate acid amount can also facilitate the improvement of the pentanal oxidation activity.It is found that there is a synergic catalytic effect between surface acidity and redox ability of the catalyst.According to the in situ DRIFTS and GC/MS analyses,pentanal can be oxidized gradually to CO_(2)and H_(2)O by the surface oxygen species with the form of adsorption in air following the Langmuir-Hinshelwood(L-H)reaction mechanism.Two reaction pathways for the pentanal oxidation process are proposed,and the conversion of the formates to carbonates may be one of the main rate-determining steps. | Jian Li Yingjie Shi Xiaoheng Fu Yun Shu Jiayu Huang Jinwei Zhu Gang Tian Jingnan Hu | 2021 | Journal of Rare Earths2021，39，9： | 2 |
| 5 | Lewis acid-oxygen vacancy interfacial synergistic catalysis over SO4^2-/Ce0.84Zr0.16O2-WO3-ZrO2 for N,N-diethylation of aniline with ethanol显示文摘Herein,a new mechanism involving Lewis acid-oxygen vacancy interfacial synergistic catalysis fo r aniline N,N-diethylation with ethanol was proposed,and the SO4^2-/Ce0.84Zr0.16O2-WO3-ZrO2 catalyst(SCWZ)with both Lewis acid sites and oxygen vacancies was synthesized by the hydrothermal method,which shows better catalytic activity than the reported solid acidic catalysts.Besides,the SO4^2-/ZrO2(SZ)and SO4^2-/WO3-ZrO2(SWZ)catalysts were also prepared and compared with SCWZ to investigate the synergistic effect of each component.The SO4^2-and WO3 mainly generate Lewis acid by bonding with ZrO2,which is beneficial for the fracture of the N-H bond in aniline.The Ce0.84Zr0.16O2 solid solution mainly plays a vital role in generating the oxygen vacancies as the interface active species,which can participate in stripping-OH from ethanol,then the carbocation will also be released,which only needs1.3805 kcal/mol energy,calculated by density functional theory(DFT),to be input.In comparison,the traditional reaction mechanism needs the Br■nsted acidic sites to promote the protonation of ethanol,then dehydration and subsequent formation of carbocation followed,and 108.6846 kcal/mol energy needs to be input,which is far higher than that of the new mechanism.The apparent activation energy(Ea)over SCWZ was measured by experiment to be 34.09 kJ/mol,which is much lower than that of SWZ(47.10 kJ/mol)and SZ(54.37 kJ/mol),illustrating comparatively preferable kinetics for SCWZ than that of SWZ and SZ.Besides,the conversion of aniline and selectivity to N,N-diethylaniline over SCWZ reach almost 100%and 73%,respectively,The SCWZ can be renewed for 4 times without rapid deactivation,and the longevity of SCWZ is longer than that of SWZ and SZ,as the loaded SO4^2-and tetragonal ZrO2 are stabilized by Ce0.84Zr0.16O2 and WO3,respectively. | Yacheng Liu Qifan Mao Xiaoyan Cao Xin Huang Kaijun Wang Can Wang Shuo Li Zhenggui Gu | 2020 | Journal of Rare Earths2020，38，11： | 0 |
| 6 | 二噁英催化分解催化剂研究进展显示文摘二噁英(PCDD/Fs)是一类剧毒的大气持久性有机污染物。热催化分解法是高效分解二噁英的主要技术手段,而催化剂是二噁英热催化分解的核心。文中从各种不同种类催化剂的催化机理及研究情况,综述了近年来催化分解二噁英催化剂的研究进展。重点讨论了钒基、锰基、铈基以及贵金属催化剂催化分解二噁英的研究现状,阐述了催化剂的催化分解机理。研究表明:二噁英催化降解的研究重点应该指向提高催化剂抗中毒性能和水热稳定性能,并进一步深入研究二噁英催化分解机理。 | 宋静 梅超强 计雯钰 徐慕涛 戴毅 徐海涛 | 2022 | 能源研究与利用2022，，2： | 0 |
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