Oxidative dehydrogenation (ODH) of mono and mixed-butenes to 1,3-butadiene (BD) was conducted using individual and dual bed catalyst systems, consisting of ZnFe2O4, Co9Fe3Bi1Mo12O51 or both. The dual bed catalyst system gave improved catalytic performance. A mechanism based on synergy between the catalysts is proposed to explain the improved overall butene conversion. The proportion of the reactants differed between the catalyst beds in the dual bed system, making better use of the catalytic activity of the second bed. The existence of all butene isomers inhibited isomerization, leading to a higher proportion of ODH reactions and thus improved the conversion of butene and the yield of BD. The packing sequences and the volume ratio of the catalysts in the bed were optimized. The results indicated that the sequence with ZnFe2O4 on top and a catalyst packing ratio of between 4:6 and 6:4 led to better activity.通过对混合丁烯氧化脱氢过程进行反应表征, 对 由ZnFe2O4 和Co9Bi1Fe3Mo12O51组成的双床层催 化剂体系中存在的协同机理进行解释; 将异构化 反应过程纳入反应体系, 得出混合丁烯转化率和 丁二烯收率上升的原因。1. 提出基于丁烯异构体在床层之间浓度重分布和 异构化效应抑制作用的协同作用机理; 2. 设计验 证实验, 从直观角度证实机理, 并优化了催化剂 的装填量和装填顺序。1. 通过单一丁烯和混合丁烯的氧化脱氢反应, 对 单一催化剂和双床层催化剂进行反应评估, 得到 相关反应数据; 2. 通过设计对比实验, 从改变参 加反应物质的直观角度对协同机理进行验证和 解释; 3. 对参加反应的双层床催化剂中两种催化 剂的装填量和装填顺序进行优化, 为进一步研究 组合型催化剂提供实验基础。1. ZnFe2O4 对两种2-丁烯有更优的催化效果, 而 Co9Bi1Fe3Mo12O51 对1-丁烯有更优的催化效果, 由两者组成的双层床催化体系对单一丁烯和混 合丁烯的反应效果都有所提升, 证明两种催化剂 之间存在协同效应。2. 双层床催化剂体系中, 两 种催化剂之间的协同作用机理是: 催化剂不同活 性导致丁烯异构体在床层之间的浓度发生重分 布, 同时由于多种异构体同时存在抑制了异构化 反应。3. 对双层床催化剂体系的装填顺序和装填 量的优化结果表明, ZnFe2O4 装填在上层, Co9Bi1Fe3Mo12O51 装填在下层, 且两者比例处于 4:6 到6:4 之间时催化效果最佳

This paper presents a novel strategy to enhance the mechanical properties of a solid catalyst. By employing a slip-casting method, an alumina membrane can be prepared on the surface of activated carbon particles uniformly. Significantly, the mechanical properties test indicates that the attrition index of activated carbon decreases from 12.6% to 2.9% due to the alumina membrane coating.

Pd/FeAlPO-5 zeolites with different Pd loading were prepared and characterized by N2 physisorption, XRD and H2-TPR. The results indicate that Pd addition has little influence on the textural structure of FeAlPO-5 zeolites. The TPR profiles of zeolites show the peak temperatures related with the reduction of Fe(III) and subsurface Pd species decrease with the increase of Pd content, suggesting the existence of interactions between Fe and Pd. The Pd/FeAlPO-5 catalysts were tested in the catalytic reduction of N2O with methane and show a better low-temperature activity in comparison with FeAlPO-5. The improved activity of Pd/FeAlPO-5 can be ascribed to the synergic effect between noble metal and iron species.

The combustion behavior of coked H−ZSM-5/H−mordenite (ZSM-5/MOR) derived from catalytic cracking of n-heptane with and without water steam has been studied by thermogravimetric analysis (TGA). Catalytic cracking under vapor atmosphere with a water−oil ratio of 2 at 650 °C created only one type of coke deposit on the catalyst. On the other hand, two types of coke can be found on the coked catalyst deactivated by catalytic cracking without water steam. These results indicated different combustion kinetic models of different types of coke. A one-coke combustion model for the regeneration of coked catalyst obtained under water steam and a two-coke combustion model for the regeneration of coked catalyst derived without water steam were conducted by using TGA, respectively. Finally, the relationship between the C/H ratios and activation energies in the combustion kinetic models were investigated by ultimate analysis.

The catalytic properties of a novel MFI-type zeolite with different SiO2/Al2O3 ratio in the dehydration of glucose to levulinic acid (LA) were investigated in this work. The results demonstrate the strength of acidic sites and the mesoporosity of the zeolites have significant effects on LA formation.

A Mn–K/CeO2–Al2O3 catalyst for the hydrogenation of benzoic acid (BAC) to benzaldehyde (BAD) has been developed. The catalyst exhibits efficient activity in the reaction and is still stable after 102 h of testing.

A series of Al–Zr mixed oxides with different molar ratios was prepared by coprecipitation method and characterized by N2 physiorption, XRD, NH3-TPD and CO2-TPD. Solid solution is formed in the mixed oxides. And the composition of the mixed oxides has significant influence on their acid–base properties. The catalysts were examined with glucose reaction in hot compressed water at 180 °C. The prepared oxides exhibit very good catalytic activity and glucose conversion can be increased from 46.6 to 85%. The products distribution is related with the acid–base property of the oxide.

The CeO2 catalysts for hydrogenation of benzoic acid to benzaldehyde were characterized by X-ray photoelectron spectroscopy (XPS). The results indicate the catalyst deactivation is due to the coke formation and the valence changes of Ce over the catalyst.

Na-W-Mn-Zr-S-P/SiO2 catalysts for oxidative coupling of methane (OCM) were prepared by incipient wetness impregnation, sol-gel and mixture slurry methods. The catalyst prepared by mixture slurry method showed the best catalytic performance among all samples. In addition, the effects of different addition sequences of Na, W, Mn, Zr, S and P on the catalytic performance were studied. The absence of Na before the addition of Mn and Zr in the catalysts preparation depressed the formation of the active phases of Mn2O3 and ZrO2 and decreased the activities of the catalysts significantly.

A series of Na-W-Mn-Zr/SiO2 catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on the Na-W-Mn-Zr/SiO2 catalyst. The catalysts were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). From the characterization results, it is found that the addition of S and P to the Na-W-Mn-Zr/SiO2 catalyst helps the formation of active phases, such as a-cristobalite, Na2WO4, ZrO2, and Na2SO4. Moreover, the addition of S and P increases the concentration of surface-active oxygen species by improving the migration of active components from the bulk phase to the surface of the catalyst. According to the activity test, impressive methane conversion and C2 hydrocarbons yield were obtained at a low temperature of 1023 K over the six-component Na-W-Mn-Zr-S-P/SiO2 catalyst, which contained 2 wt% S and 0.4 wt% P simultaneously. The deactivation of Na-W-Mn-Zr-S-P/SiO2 was due to the loss of surface active components.