105-08-8Relevant articles and documents
Surface synergistic effect in well-dispersed Cu/MgO catalysts for highly efficient vapor-phase hydrogenation of carbonyl compounds
Liu, Hanwen,Hu, Qi,Fan, Guoli,Yang, Lan,Li, Feng
, p. 3960 - 3969 (2015)
The highly efficient vapor-phase selective hydrogenation of carbonyl compounds (e.g. furfural (FAL) and dimethyl 1,4-cyclohexane dicarboxylate (DMCD)) to corresponding alcohols was achieved excellently over well-dispersed MgO-supported copper catalysts (Cu/MgO), which were prepared by an alternative separate nucleation and aging step method. The characterization results revealed that the structure and catalytic performance of the as-formed Cu/MgO catalysts were profoundly affected by Cu loading. Especially, the results confirmed that the decrease in the Cu loading could lead to the improvement of metal dispersion and the formation of more surface strong Lewis basic sites. In the vapor-phase selective hydrogenation of FAL to furfuryl alcohol (FOL) and DMCD to 1,4-cyclohexane dimethanol (CHDM), two Cu/MgO catalysts with Cu loadings of 27.6 wt% and 70.9 wt% exhibited superior catalytic performance with higher conversions (>97.3%) and selectivities to alcohols (>96.0%) compared to the other supported ones. The high efficiency of the as-formed Cu/MgO catalysts was mainly attributed to the surface synergistic catalytic effect between the catalytically active metallic copper species and the Lewis basic sites, which held the key to the hydrogenation reaction related to the hydrogen dissociation and the activation of the carbonyl groups.
Conversion of bis(2-hydroxyethylene terephthalate) into 1,4-cyclohexanedimethanol by selective hydrogenation using RuPtSn/Al2O3
Hou, Danfeng,Xin, Jiayu,Lu, Xingmei,Guo, Xiaonan,Dong, Huixian,Ren, Baozeng,Zhang, Suojiang
, p. 48737 - 48744 (2016)
1,4-Cyclohexanedimethanol (CHDM) is a highly valued and widely used monomer in the polymer industry. Bis(2-hydroxyethylene terephthalate) (BHET), the product of glycolysis of waste PET, is an excellent raw material for the preparation of CHDM. Herein, a series of monometallic, bimetallic and trimetallic supported catalysts were prepared for the one-pot conversion of BHET into CHDM by the impregnation method and good performance was found over trimetallic RuPtSn/Al2O3 catalysts containing various active sites to catalyze the hydrogenation of the phenyl and carbonyl groups. The influences of various reaction parameters including temperature, pressure and time on the hydrogenation reaction were studied, and 100% conversion and 87.1% yield of CHDM were obtained with the trimetallic supported catalyst with Ru/Sn 1.5. Moreover, through the comparison between various methods for the preparation of CHDM, the conversion of BHET into CHDM by the one-pot method is considered one of the most competitive methods.
Single-step, highly active, and highly selective nanoparticle catalysts for the hydrogenation of key organic compounds
Raja, Robert,Khimyak, Tetyana,Thomas, John Meurig,Hermans, Sophie,Johnson, Brian F. G.
, p. 4638 - 4642 (2001)
Pores for cluster catalysts: Nanoparticles of both Ru5Pt and Ru10Pt2, uniformly distributed along the inner walls of mesoporous silica, exhibit high catalytic performance in the single-step hydrogenation of dimethyl terephthalate (DMT, to 1,4-cyclohexanedimethanol (CHDM); see scheme), of benzoic acid (to cyclohexane carboxylic acid), and of naphthalene (in the presence of sulfur) to cisdecalin.
Aluminum-doped zirconia-supported copper nanocatalysts: Surface synergistic catalytic effects in the gas-phase hydrogenation of esters
Hu, Qi,Fan, Guoli,Yang, Lan,Li, Feng
, p. 3501 - 3510 (2014)
The efficient gas-phase selective hydrogenation of a series of esters to the corresponding alcohols was achieved over well-dispersed aluminum-doped zirconia-supported copper nanocatalysts (Cu/Al-ZrO2), which were prepared through a homogeneous coprecipitation route in the presence of cetyl trimethyl ammonium bromide. The characterization revealed that the structure and catalytic performance of Cu/Al-ZrO2 nanocatalysts were profoundly affected by the addition of Al. Compared with the Al-free catalyst, Al-doped materials had higher specific surface areas and smaller copper nanoparticles. In particular, the results confirmed that the incorporation of Al into the ZrO2 framework could form tetrahedrally coordinated Al3+ species, leading to the improvement of metal dispersion and the formation of more surface Lewis acid sites. In the gas-phase selective hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG), 100% DMO conversion, 97.1% EG selectivity, and a high turnover frequency of 16.9'h-1 were achieved over Cu/Al-ZrO2 catalyst with a Al/(Cu+Zr+Al) mass ratio of 0.1. The high efficiency of Cu/Al-ZrO2 catalysts in DMO hydrogenation was attributed mainly to the surface synergistic catalytic effect between highly dispersed metallic copper species and strong Lewis acid sites, which promoted the hydrogenation reaction related to the ester groups, unlike the single case of Cu+Cu0 synergy reported previously that was found to control the extent of hydrogenation. The obtained catalysts displayed excellent catalytic performance in the gas-phase hydrogenation of other esters including dimethyl succinate, dimethyl maleate, dimethyl adipate, and 1,4-cycolhexane dicarboxylate. The effects of doping: The gas-phase hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG) is conducted on well-dispersed Al-doped Zr-supported Cu nanocatalysts, achieving 100% conversion with 97.1% selectivity. The unprecedented catalytic performance is ascribed to the surface synergistic catalytic effect between active metallic Cu sites and strong Lewis acid sites. MG=Methyl glycolate, 1,2-BDO=1,2-butanediol.
Single-step conversion of dimethyl terephthalate into cyclohexanedimethanol with Ru5PtSn, a trimetallic nanoparticle catalyst
Hungria, Ana B.,Raja, Robert,Adams, Richard D.,Captain, Burjor,Thomas, John Meurig,Midgley, Paul A.,Golovko, Vladimir,Johnson, Brian F. G.
, p. 4782 - 4785 (2006)
Highly active and selective: A supported Ru5PtSn nanoparticle cluster (the picture shows an axial projection of a tomogram), prepared from the carbonyl cluster [PtRu5(CO)15(μ-SnPh 2)(μ6-C)], is an excellent catalyst in the single-step hydrogenation of dimethyl terephthalate to cyclohexanedimethanol under mild conditions (100°C, 20 bar H2). (Figure Presented).
Lewis-base-promoted copper-based catalyst for highly efficient hydrogenation of dimethyl 1,4-cyclohexane dicarboxylate
Zhang, Shaoyan,Fan, Guoli,Li, Feng
, p. 2389 - 2393 (2013)
The gas-phase hydrogenation of dimethyl 1,4-cyclohexane dicarboxylate to 1,4-cyclohexane dimethanol was performed on a well-dispersed Cr-free supported copper-based catalyst derived from a Cu-Mg-Al layered double hydroxide precursor, and achieved a lasting 100% conversion with 99.8% selectivity up to 200 hours. The unprecedented catalytic performance is ascribed to the synergistic effect between surface active Cu0 sites and Lewis base sites.
Re/AC catalysts for selective hydrogenation of dimethyl 1, 4-cyclohexanedicarboxylate to 1, 4-cyclohexanedimethanol: Essential roles of metal dispersion and chemical environment
Dong, Yanan,Liang, Changhai,Luo, Jingjie,Qu, Enhui,Zhou, Yixue
, (2020)
Rhenium, although viewed as one of the noble metals with lower-price, has been commonly used as doping element in the bimetallic catalysts due to its middlebrow to activate hydrogen. Its major role as catalyst is less frequently mentioned. In this work, rhenium has been decorated on the surface of activated carbon and used for the selective hydrogenation of dimethyl 1, 4-cyclohexanedicarboxylate (DMCD) to 1, 4-cyclohexanedimethanol (CHDM). Characterizations suggested that ReOx particles were anchored occupying the surface oxygenated groups on pre-functionalized carbon. Rhenium decoration modified both the textural and chemical properties of the samples. Electrons were easily transferred from Re to the neighboring C atoms as a result of the formation of fine ReOx particles. Medium strong acid sites were generated and rhenium species in the reduced states could be still maintained under appropriate rhenium dispersion. The moderate hydrogenation ability of rhenium catalyst partially restrained the excessive hydrogenation of CHDM to other by-products. Rational decoration of 5 wt% Re performed the better catalytic performance with complete conversion of diester and 66 % yield of diol. The specific rate reached 9.5×102 mmolDMCD?gRe-1?h-1 at 220 °C under 10 MPa H2.
A Highly Active Manganese Catalyst for Enantioselective Ketone and Ester Hydrogenation
Widegren, Magnus B.,Harkness, Gavin J.,Slawin, Alexandra M. Z.,Cordes, David B.,Clarke, Matthew L.
, p. 5825 - 5828 (2017)
A new hydrogenation catalyst based on a manganese complex of a chiral P,N,N ligand has been found to be especially active for the hydrogenation of esters down to 0.1 mol % catalyst loading, and gives up to 97 % ee in the hydrogenation of pro-chiral deactivated ketones at 30–50 °C.
Copper nanoparticles socketed in situ into copper phyllosilicate nanotubes with enhanced performance for chemoselective hydrogenation of esters
Gong, Xiaoxiao,Wang, Meiling,Fang, Huihuang,Qian, Xiaoqi,Ye, Linmin,Duan, Xinping,Yuan, Youzhu
, p. 6933 - 6936 (2017)
Copper nanoparticles exsoluted in situ under a reducing atmosphere at elevated temperatures are socketed into the parent copper phyllosilicate nanotubes and exhibit excellent catalytic performance and superior stability for the selective hydrogenation of various esters to alcohols.
The role of hydrotalcite-modified porous alumina spheres in bimetallic RuPd catalysts for selective hydrogenation
Chen, Jiali,Guo, Li,Zhang, Fazhi
, p. 19 - 23 (2014)
By utilizing alumina previously modified by in-situ growth of varying amounts of hydrotalcites, a series of heterogeneous bimetallic catalysts with constant low loading (0.3 wt.%) and identical Ru:Pd ratio (1:1) were prepared based on co-impregnation for selective hydrogenation of dimethyl terephthalate to dimethyl cyclohexane-1,4-dicarboxylate. Nanoparticles confined in the reticular structure were observed. The resulting candidates show the superior catalytic activity over that supported on the unmodified alumina, and reach the highest in the optimized sample RuPd/HTC-Al2O 3-1. This promotion and optimization effect could be ascribed to the improved dispersion and more supply of hydrogen and acid sites especially with medium strength.
