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| 1 | Efficient synthesis of poly(oxymethylene) dimethyl ethers over PVP-stabilized heteropolyacids through self-assembly显示文摘A series of polyvinylpyrrolidone-stabilized heteropolyacids(PVP-HPAs)are generated by self-assembly of HPAs and PVP in methanol.The PVP-HPAs are then employed as catalysts for the synthesis of poly(oxymethylene)dimethyl ethers(DMMn,n1)by the methanolysis of trioxane.The results suggest that the acidity of PVP-HPAs is tunable by changing the ratio of PVP and HPAs,which is a key factor for the selectivity of the DMMn product.By optimizing the composition and reaction conditions,two types of PVP-HPA,PVP-phosphotungstic acid(PVP-HPW)in a PVP/HPW ratio of 1/4:1 and PVP-silicotungstic acid(PVP-HSi W)in a PVP/HSi W ratio of 1/4:3/4,respectively afford 52.4%and 50.3%yields of DMM2–5.The optimized catalysts are reusable for a minimum of 10 times without a significant drop in performance. | Xiaolong Fang Jin Chen Linmin Ye Haiqiang Lin Youzhu Yuan | 2015 | Science China Chemistry2015，58，1： | 4 |
| 2 | Yttrium chloride-modified Au/AC catalysts for acetylene hydrochlorination with improved activity and stability显示文摘The addition of yttrium chloride(YCl_3) to an activated carbon-supported Au catalyst(Au/AC) can markedly promote the catalytic performance of acetylene hydrochlorination to the vinyl chloride monomer(VCM), The structure and physicochemical features of the YCl_3-modified catalysts(Y-Au/AC)were measured by X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed reduction, C_2 H_2-temperature programmed desorption, and scanning transmission electron microscopy.The presence of YCl_3 was found suppressing the reduction of highly oxidized Au^(δ+)(δ=1,3) to metallic Au^0 dependently and thus retard the agglomeration of Au nanoparticles during the reaction. In addition,the additive of YCl_3 to the Au/AC catalyst greatly inhibits the coke deposition on the catalyst surface. The optimized catalyst with an atomic ratio of Y/Au = 5(1 wt% Au loading weight) yields an 87.8% acetylene conversion and almost 100% selectivity for VCM under the reaction of GHSV(C_2 H_2) = 800 h^(-1) at 180 ℃.The durability test indicates that the 5 Y-1 Au/AC catalyst maintains high catalytic activity for more than2300 h at 30 h^(-1) GHSV(C_2 H_2) and 180 ℃, indicating great promise as a non-mercury catalyst for PVC manufacture. | Jinhuo Ke Yuxin Zhao Yan Yin Kun Chen Xinping Duan Linmin Ye Youzhu Yuan | 2017 | Journal of Rare Earths2017，35，11： | 1 |
| 3 | Efficient low-temperature soot combustion by bimetallic Ag–Cu/SBA-15 catalysts显示文摘In this study, the effects of copper(Cu) additive on the catalytic performance of Ag/SBA-15 in complete soot combustion were investigated. The soot combustion performance of bimetallic Ag–Cu/SBA-15 catalysts was higher than that of monometallic Ag and Cu catalysts. The optimum catalytic performance was acquired with the 5 Ag_1-Cu_(0.1)/SBA-15 catalyst, on which the soot combustion starts at T_(ig)= 225°C with a T_(50)= 285°C. The temperature for 50% of soot combustion was lower than that of conventional Ag-based catalysts to more than 50°C(Aneggi et al., 2009). Physicochemical characterizations of the catalysts indicated that addition of Cu into Ag could form smaller bimetallic Ag–Cu nanolloy particles, downsizing the mean particle size from 3.7 nm in monometallic catalyst to 2.6 nm in bimetallic Ag–Cu catalyst. Further experiments revealed that Ag and Cu species elicited synergistic effects, subsequently increasing the content of surface active oxygen species. As a result, the structure modifications of Ag by the addition of Cu strongly intensified the catalytic performance. | Zhaojun Wen Xinping Duan Menglin Hu Yanning Cao Linmin Ye Lilong Jiang Youzhu Yuan | 2018 | Journal of Environmental Sciences2018，30，2： | 1 |
| 4 | Synergistic effects of bimetallic Cu-Fe/SiO_2 nanocatalysts in selective hydrogenation of diethyl malonate to 1,3-propanediol显示文摘Cu_x-Fe_y/SiO_2 catalysts were prepared using urea-assisted sol-gel method.The structure and physicochemical properties of the catalysts were characterized using N_2 adsorption-desorption,transmission electron microscopy,H_2-temperature-programmed reduction,powder X-ray diffraction,and X-ray photoelectron spectroscopy.Compared with monometallic Cu or Fe catalysts,the bimetallic Cu_x-Fe_y/SiO_2 catalysts exhibited enhanced catalytic performance for the selective hydrogenation of diethyl malonate to1,3-propanediol.The bimetallic catalyst with an optimal Cu/Fe atomic ratio of 2 exhibited the highest activity,which yielded 96.3%conversion to diethyl malonate and 93.3%selectivity to 1,3-propanediol under the optimal reaction conditions.Characterization results revealed that interactions between Cu and Fe contributed to the improvement of diethyl malonate conversion and selectivity to 1,3-propanediol.The X-ray photoelectron spectroscopy results revealed that the addition of appropriate amount of Fe species enhanced the reduction of Cu^(2+) species,thereby increasing the Cu° species on the surface of bimetallic catalyst.It led to a better chemisorption capacity of hydrogen and further promoted of the activation of hydrogen molecule.The ethyl acetate temperature-programmed desorption results indicated that the FeO_x species provided the additional adsorption sites for substrate molecules,and they activated the C=O bond.The improved catalytic performance of bimetallic Cu_x-Fe_y/SiO_2 catalyst was mainly attributed to the synergistic effect between Cu° and FeO_x species. | Le He Xiaoxiao Gong Linmin Ye Xinping Duan Youzhu Yuan | 2016 | Journal of Energy Chemistry2016，25，6： | 1 |
| 5 | Improved performance of magnetically recoverable Ce-promoted Ni/Al 2 O 3 catalysts for aqueous-phase hydrogenolysis of sorbitol to glycols显示文摘 | Linmin Ye Xinping Duan Haiqiang Lin Youzhu Yuan | 2011 | Catalysis Today2011，，1： | 1 |
| 6 | Improved performance of magnetically recoverable Ce-promoted Ni/Al2O3 catalysts for aqueous-phase hydrogenolysis of sorbitol to glycols显示文摘 | Ye Linmin Duan Xinping Lin Haiqiang | | 0，，01： | 1 |
| 7 | Low temperature catalytic conversion of methane to formic acid by simple vanadium compound with use of H_2O_2显示文摘Selective oxidation of methane with hydrogen peroxide was catalyzed by several simple vanadium compounds in CH3CN.The reaction could afford formic acid as the major product.Vanadyl oxysulfate(VOSO4) was found to be an efficient catalyst.Specifically,the selectivity to formic acid of 70% at a methane conversion of 6.5% could be achieved over the VOSO4 catalyst under the reaction conditions of methane pressure 3.0 MPa and temperature 333 K for 4 h.The UV-Vis spectroscopic measurements revealed that the formation of V5+ species during the reaction might be vital for the methane activation.The reaction probably proceeded via radical mechanism. | Xin Wei Linmin Ye Youzhu Yuan | 2009 | Journal of Natural Gas Chemistry2009，18，3： | 1 |
| 8 | Halide-free carbonylation of methanol with H-MOR supported CuCeO_(x) catalysts显示文摘Heterogeneous halide-free carbonylation of methanol to acetates,including methyl acetate(MA)and acetic acid,using non-precious metal catalysts has been a topic of interest for decades.The key issue is that the water produced by methanol dehydration inhibits the formation of acetyl species and reduces the MA selectivity.Here,we report that CuCeO_(x)/H-mordenite(H-MOR)catalyst can nearly eliminate the inhibiting effect of water on carbonylation by a water-gas shift reaction(WGSR)on-site,and can thus achieve 96.5%methanol conversion with 87.4%MA selectivity for the halide-free carbonylation of methanol.The results of powder X-ray diffraction,transmission electron microscopy,and scanning electron microscopy show that the Cu and Ce species are highly dispersed on H-MOR even when the CuCeO_(x)contents are as high as 29 wt-%.Fourier transform infrared spectroscopy and CO chemisorption analysis reveal that a small portion of Cu species can migrate into the channel of H-MOR when CuCeO_(x)/H-MOR is calcined at 500℃and these Cu species are converted into Cu^(+) sites upon reduction.The Cu^(+) sites facilitate the WGSR and are also active sites for methanol carbonylation.The introduction of Ce benefits the inhibition of coke deposits and thus enhances the catalyst stability. | Chaoli Tong Jiachang Zuo Danlu Wen Weikun Chen Linmin Ye Youzhu Yuan | 2021 | Frontiers of Chemical Science and Engineering2021，15，5： | 0 |
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