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| 1 | 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 |
| 2 | 低温钒基脱硝催化剂的研究进展显示文摘钒基催化剂在中高温环境下具有较好的脱硝活性,但是在工作环境温度低于200℃时,其脱硝活性很低,因此需要通过助剂掺杂、改变制备工艺对钒基催化剂在低温下的脱硝活性进行改善。本文从载体、助剂、制备方法三个方面进行详细分析,阐述了其各自对钒基催化剂在低温下实现高效率抗硫脱硝的机理及意义。最后指出目前钒基催化剂抗硫脱硝存在的问题,以及对下一步需要研究的方向进行总结。 | 李泽清 陈红萍 魏永林 | 2022 | 广州化工2022，50，7： | 1 |
| 3 | 堇青石表面化学气相沉积二氧化钛的负载机理及负载动力学显示文摘以酸蚀改性堇青石为基体,利用化学气相沉积法(CVD)在基体上负载TiO_(2),采用扫描电子显微镜、能谱仪、X射线衍射仪、BET比表面积法等对负载了TiO_(2)的堇青石进行表征,测定不同温度下的负载速度。结果表明:负载了TiO_(2)的堇青石主要由(211)及(200)取向的锐钛矿TiO_(2)组成,呈八面体和立方体形态,BET比表面积达78.80 m_(2)·g_(−1),平均孔径为9.80 nm,具有双峰分布特征。负载过程为TiCl_(4)及O_(2)向堇青石基体扩散吸附,TiCl_(4)分解为Ti_(4+)并在高氧势下进入基体晶格形成TiO_(2)晶核,并经过择优取向和外延式生长,其负载沉积速率方程为V=6807exp(-7255/T)P^(0)_(TiCl_(4)),其中T为负载温度,P^(0)_(TiCl_(4)),为气相TiCl_(4)的分压。 | 杨眉 刘良文 郑珩 卢静祥 王静怡 | 2022 | 稀有金属材料与工程2022，51，3： | 1 |
| 4 | SCR催化剂抗碱(土)金属中毒及再生研究进展显示文摘控制氮氧化物排放技术中,选择性催化还原(SCR)法因脱硝效率高且技术成熟稳定成为目前广泛应用的技术,烟气中碱(土)金属导致催化剂活性中心的失活现象是目前工业烟气SCR脱硝催化剂应用的一个瓶颈.基于此,开发有良好碱(土)金属耐受性的低温高效SCR催化剂是当务之急.本文整理和归纳了SCR催化剂碱(土)金属中毒机理,探讨了提高催化剂抗碱(土)金属中毒的改性方法及作用机制、中毒催化剂的再生方法及量子化学计算的应用,最后对SCR催化剂的未来研究发展方向进行了展望. | 兰馨 赵玲 | 2022 | 环境化学2022，41，11： | 1 |
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