Methane conversion over nanostructured Pt/γAl2O3 catalysts in dielectric-barrier discharge

Spherical nanostructured γ-Al₂O₃ granules were prepared by combining the modified Yoldas process and oil-drop method, followed by the Pt impregnation inside mesopores of the granules by incipient wetness method. Prepared Pt/γ-Al₂O₃ catalysts were reduced by novel method using plasma, which was named plasma assisted reduction (PAR), and then used for methane conversion in dielectric-barrier discharge (DBD). The effect of Pt loading, calcination temperature on methane conversion, and selectivities and yields of products were investigated. Prepared Pt/γ-Al₂O₃ catalysts were successfully reduced by PAR. The main products of methane conversion were the light alkanes such as C₂H₆, C₃H₈ and C₄H₁₀ when the catalytic plasma reaction was carried out with Pt/γ-Al₂O₃ catalyst. Methane conversion was in the range of 38–40% depending on Pt loading and calcination temperature. The highest yield of C₂H₆ was 12.7% with 1 wt% Pt/γ-Al₂O₃ catalysts after calcinations at 500 ‡C.     

Methane conversion to higher hydrocarbons in a dielectric-barrier discharge reactor with Pt/γ-Al2O3 catalyst

Plasma catalytic reactions were applied to the conversion of methane to C₂, C₃ or higher hydrocarbons in a dielectric-barrier discharge (DBD) reactor at atmospheric pressure. Methane conversion was increased with the increase of Pt loading on γ-Al₂O₃. The highest C₂H₆ selectivity was 50.3% when 3 wt% Pt/γ-Al₂O₃ catalyst was calcined at 573 K. Methane conversion was increased with the increase of the catalyst weight in DBD reactor. The major products were C₂H₆ and C₃H₈, which were independent of catalyst weight in the presence of catalyst.     

Selective methanation of CO over supported Ru catalysts

The catalytic performance of supported ruthenium catalysts for the selective methanation of CO in the presence of excess CO₂ has been investigated with respect to the loading (0.5–5.0 wt.%) and mean crystallite size (1.3–13.6 nm) of the metallic phase as well as with respect to the nature of the support (Al₂O₃, TiO₂, YSZ, CeO₂ and SiO₂). Experiments were conducted in the temperature range of 170–470 °C using a feed composition consisting of 1%CO, 50% H₂ 15% CO₂ and 0–30% H₂O (balance He). It has been found that, for all catalysts investigated, conversion of CO₂ is completely suppressed until conversion of CO reaches its maximum value. Selectivity toward methane, which is typically higher than 70%, increases with increasing temperature and becomes 100% when the CO₂ methanation reaction is initiated. Increasing metal loading results in a significant shift of the CO conversion curve toward lower temperatures, where the undesired reverse water–gas shift reaction becomes less significant. Results of kinetic measurements show that CO/CO₂ hydrogenation reactions over Ru catalysts are structure sensitive, i.e., the reaction rate per surface metal atom (turnover frequency, TOF) depends on metal crystallite size. In particular, for Ru/TiO₂ catalysts, TOFs of both CO (at 215 °C) and CO₂ (at 330 °C) increase by a factor of 40 and 25, respectively, with increasing mean crystallite size of Ru from 2.1 to 4.5 nm, which is accompanied by an increase of selectivity to methane. Qualitatively similar results were obtained from Ru catalysts supported on Al₂O₃. Experiments conducted with the use of Ru catalyst of the same metal loading (5 wt.%) and comparable crystallite size show that the nature of the metal oxide support affects significantly catalytic performance. In particular, the turnover frequency of CO is 1–2 orders of magnitude higher when Ru is supported on TiO₂, compared to YSZ or SiO₂, whereas CeO₂- and Al₂O₃-supported catalysts exhibit intermediate performance. Optimal results were obtained over the 5%Ru/TiO₂ catalyst, which is able to completely and selectively convert CO at temperatures around 230 °C. Addition of water vapor in the feed does not affect CO hydrogenation but shifts the CO₂ conversion curve toward higher temperatures, thereby further improving the performance of this catalyst for the title reaction. In addition, long-term stability tests conducted under realistic reaction conditions show that the 5%Ru/TiO₂ catalyst is very stable and, therefore, is a promising candidate for use in the selective methanation of CO for fuel cell applications.     

Catalytic Conversion of N2O to N2 over Metal-Based Catalysts in the Presence of Hydrocarbons and Oxygen

The catalytic conversion of N₂O to N₂ in the presence or the absence of propene and oxygen was studied. The catalysts examined in this work were synthesized impregnating metals (Rh, Ru, Pd, Co, Cu, Fe, In) on different supports (Al₂O₃, SiO₂, TiO₂, ZrO₂ and calcined hydrotalcite MgAl₂(OH)₈·H₂O). The experimental results varied both with the type of the active site and with the type of the support. Rh and Ru impregnated on -alumina exhibited the highest activity. The performance of the above most promising catalysts was studied using various hydrocarbons (CH₄, C₃H₆, C₃H₈) as reducing agents. These experimental results showed that the type of reducing agent does not affect the reaction yield. The temperature where complete conversion of N₂O to N₂ was measured was independent of the reductant type. The activity of the most active catalysts was also measured in the presence of SO₂ and H₂O in the feed. A shift of the N₂O conversion versus temperature curve to higher temperatures was observed when SO₂ and H₂O were added, separately or simultaneously, to the feed. The inhibition caused by SO₂ was attributed to the formation of sulfates and that caused by water to the competitive chemisorption of H₂O and N₂O on the same active sites.     

Partial oxidation of methane to synthesis gas via the direct reaction scheme over Ru/TiO2 catalyst

The partial oxidation of methane to synthesis gas has been investigated over various supported metal catalysts. The effects of operational variables on mass and heat transport resistances were investigated for defining the kinetic regime. It is observed that, in the absence of significant mass and heat transfer resistances, high selectivity (up to 65%) to synthesis gas is obtained over Ru/TiO₂ catalysts in the low methane conversion range ( ) whereas only negligibly small selectivity to synthesis gas is observed over all other catalysts investigated under similar conditions. This indicates that the Ru/TiO₂ catalyst possesses unique properties, offering high selectivity to synthesis gas formation via the direct reaction scheme, whereas the other catalysts promote the sequence of total oxidation of methane to CO₂ and H₂O, followed by reforming reactions to synthesis gas. An increase of selectivity to synthesis gas, in the presence of oxygen, is achieved over the Ru/TiO₂ catalyst by multi-feeding oxygen, which is attributed to suppression of deep oxidation of H₂ and CO.     

The effect of synthesis gas composition on the Fischer–Tropsch synthesis over Co/γ-Al2O3 and Co–Re/γ-Al2O3 catalysts

The Fischer–Tropsch synthesis over Co/γ-Al₂O₃ and Co–Re/γ-Al₂O₃ was investigated in a fixed-bed reactor at 20 bar and 483 K using feed gases with molar H₂/CO ratios of 2.1, 1.5 and 1.0 simulating synthesis gas derived from biomass. With lower H₂/CO ratios in the feed, the CO conversion and the CH₄ selectivity decreased, while the C₅₊ selectivity and olefin/paraffin ratio for C₂–C₄ increased slightly. The water–gas shift activity was low for both catalysts, resulting in high molar usage ratios of H₂/CO (close to 2.0), even at the lower inlet ratios (i.e. 1.5 and 1.0). For both catalysts, the drop in the production rate of hydrocarbons when shifting from an inlet ratio of 2.1 to 1.5 was significant mainly because the H₂/CO usage ratio did not follow the change in the inlet ratio. The hydrocarbon selectivities were rather similar for inlet H₂/CO ratios of 2.1 and 1.5, while significantly deviating from those for an inlet ratio of 1.0. With the studied catalysts, it is possible to utilize the advantages of an inlet ratio of 1.0 (higher selectivity to C₅₊, lower selectivity to CH₄, no water–gas shifting of the bio-syngas needed prior to the FT reactor) if a low syngas conversion is accepted.     

Effect of Ru addition to Co/SiO2/HZSM-5 catalysts on Fischer–Tropsch synthesis of gasoline-range hydrocarbons

Microporous HZSM-5 zeolite and mesoporous SiO₂ supported Ru–Co catalysts of various Ru adding amounts were prepared and evaluated for Fischer–Tropsch synthesis (FTS) of gasoline-range hydrocarbons (C₅–C₁₂). The tailor-made Ru–Co/SiO₂/HZSM-5 catalysts possessed both micro- and mesopores, which accelerated hydrocracking/hydroisomerization of long-chain products and provided quick mass transfer channels respectively during FTS. In the same time, Ru increased Co reduction degree by hydrogen spillover, thus CO conversion of 62.8% and gasoline-range hydrocarbon selectivity of 47%, including more than 14% isoparaffins, were achieved simultaneously when Ru content was optimized at 1 wt% in Ru–Co/SiO₂/HZSM-5 catalyst.     

Study of ruthenium supported on Ta2O5–ZrO2 and Nb2O5–ZrO2 as catalysts for the partial oxidation of methane

Ru-based catalysts supported on Ta₂O₅–ZrO₂ and Nb₂O₅–ZrO₂ are studied in the partial oxidation of methane at 673–873 K. Supports with different Ta₂O₅ or Nb₂O₅ content were prepared by a sol–gel method, and RuCl₃ and RuNO(NO₃)₃ were used as precursors to prepare the catalysts (ca. 2 wt.% Ru). At 673 K high selectivity to CO₂ was found. An increase of temperature up to 773 K produced an increase in the selectivity to syngas (H₂/CO = 2.2–3.1), and this is related with the transformation of RuO₂ to metallic Ru as was determined from XRD and XPS results. At 873 K and with co-fed CO₂ an increase of the catalytic activity and CO selectivity was found. A TOF value of 5.7 s⁻¹ and H₂/CO ratio ca. 1 was achieved over Ru(Cl)/6TaZr. Catalytic results are discussed as a function of the support composition and characteristics of Ru-based phases.     

Conversion of methane through dielectric-barrier discharge plasma

Methane coupling to produce C₂ hydrocarbons through a dielectric-barrier discharge (DBD) plasma reaction was studied in four DBD reactors. The effects of high voltage electrode position, different discharge gap, types of inner electrode, volume ratio of hydrogen to methane and air cooling method on the conversion of methane and distribution of products were investigated. Conversion of methane is obviously lower when a high voltage electrode acts as an outer electrode than when it acts as an inner electrode. The lifting of reaction temperature becomes slow due to cooling of outer electrode and the temperature can be controlled in the expected range of 60°C–150°C for ensuring better methane conversion and safe operation. The parameters of reactors have obvious effects on methane conversion, but it only slightly affects distribution of the products. The main products are ethylene, ethane and propane. The selectivity of C₂ hydrocarbons can reach 74.50% when volume ratio of hydrogen to methane is 1.50. __________ Translated from Petrochemical Technology, 2007, 36(11): 1099–1103 [译自: 石油化工]     

Effect of H2S on the hydrogenation of carbon dioxide over supported Rh catalysts

The hydrogenation of CO₂ was studied on supported noble metal catalysts in the presence of H₂S. In the reaction gas mixture containing 22 ppm H₂S the reaction rate increased on TiO₂ and on CeO₂ supported metals (Ru, Rh, Pd), but on all other supported catalysts or when the H₂S content was higher (116 ppm) the reaction was poisoned. FTIR measurements revealed that in the surface interaction of H₂ + CO₂ on Rh/TiO₂ Rh carbonyl hydride, surface formate, carbonates and surface formyl were formed. On the H₂S pretreated catalyst surface formyl species were missing. TPD measurements showed that adsorbed H₂S desorbed as SO₂, both from TiO₂-supported metals and from the support. IR, XP spectroscopy and TPD measurements demonstrated that the metal became apparently more positive when the catalysts were treated with H₂S and when the sulfur was built into the support. The promotion effect of H₂S was explained by the formation of new centers at the metal/support interface.     

Performance of a slurry bubble column reactor for Fischer-Tropsch synthesis: Determination of optimum condition

The CO conversion and selectivity to C₁+ and C₁₁+ wax products over Co/Al₂O₃ as well as Ru/Co/Al₂O₃ Fischer-Tropsch (F-T)catalysts were investigated by varying reaction temperature (210-250 °C), system pressure (1.0-3.0 MPa), GHSV (1000-6000 L/kg/h), superficial gas velocity (1.7-13.6 cm/s) and slurry concentration (9.09-26.67 wt.%) in a slurry bubble column reactor (0.05 m diameter × 1.5 m height) to determine the optimum operating conditions. Squalane or paraffin wax was used as initial liquid media. The overall CO conversion increased with increasing reaction temperature, system pressure and catalyst concentration. However, the local maximum CO conversion was exhibited at GHSV of 1500-2000 L/kg/h and superficial gas velocity of 3.4-5.0 cm/s. The CO conversion in the case of Ru/Co/Al₂O₃ was much higher and stable than that in the case of Co/Al₂O₃. The selectivity to C₁₁+ wax products increased slightly with increasing GHSV; on the other hand, it decreased with increasing reaction temperature, system pressure, and solid concentration in a slurry bubble column reactor. It could be concluded that the optimum operating conditions based on the yield of hydrocarbons and wax products were; U_G = 6.8-10 cm/s, Cs = 15 wt.%, T = 220-230 °C, P = 2.0 MPa in a slurry bubble column reactor for F-T synthesis.     

Integrated coal pyrolysis with CO2 reforming of methane over Ni/MgO catalyst for improving tar yield

A new process to integrate coal pyrolysis with CO₂ reforming of methane over Ni/MgO catalyst was put forward for improving tar yield. And several Chinese coals were used to confirm the validity of the process. The experiments were performed in an atmospheric fixed-bed reactor containing upper catalyst layer and lower coal layer to investigate the effect of pyrolysis temperature, coal properties, Ni loading and reduction temperature of Ni/MgO catalysts on tar, water and char yields and CH₄ conversion at fixed conditions of 400 ml/min CH₄ flow rate, 1:1 CH₄/CO₂ ratio, 30 min holding time. The results indicated that higher tar yield can be obtained in the pyrolysis of all four coals investigated when coal pyrolysis was integrated with CO₂ reforming of methane. For PS coal, the tar, water and char yield is 33.5, 25.8 and 69.5 wt.%, respectively and the CH₄ conversion is 16.8%, at the pyrolysis temperature of 750 °C over 10 wt.% Ni/MgO catalyst reduced at 850 °C. The tar yield is 1.6 and 1.8 times as that in coal pyrolysis under H₂ and N₂, respectively.     

Heterogen katalysierte Hydrierung von Kohlendioxid zu Methan unter erhöhten Drücken

Ni‐ and Ru‐containing supported catalysts were prepared and used for the CO₂ hydrogenation to methane (Sabatier reaction) in the gas phase. Tests on the effect of the reaction temperature and pressure were in the focus. ZrO₂ and γ‐Al₂O₃ were used as suitable catalyst supports. CO₂ and H₂ conversions of 70 – 80 % and selectivity to methane of > 99 % were reached. TiO₂ and SiO₂ based catalysts exclusively lead to CO and seem to be not suited for this reaction. The investigations on the pressure effect impressively demonstrated the influence on the chemical equilibrium. CO₂ and H₂ can be nearly completely converted with > 99.9 % selectivity to methane over Ru/ZrO₂.     

An Integrated Process for D-Sorbitol Production over NiO/TiO2 Supported Ru Nanocatalyst: A Greener Approach

The catalytic transformation of D-glucose towards D-sorbitol is a well-established process in the biorefinery industry. Normally, this batch-wise hydrogenation over metallic catalysts suffers from several troubles such as low yielding and facile catalyst deactivation. To address these challenges, we, hereby fabricated 5NiO/TiO₂-supported Ru nanocatalysts (Ru-5NiO/TiO₂, 1.0 and 5.0 wt% Ru) and examined their efficacy in the continuous-flow reduction of D-glucose aqueous solution (20 wt%) to produce D-sorbitol for the first time. In this study, D-glucose conversion and D-sorbitol yield were represented as a function of residence time, where the feeding rate of D-glucose was systematically controlled to maximize the outcome of D-sorbitol. Remarkably, D-glucose was fully converted to 99.0% selectivity of D-sorbitol under optimized reaction conditions (100 °C, 8 MPa H₂ with a flow rate of 100 L h^?1). The experimental results showed that the mean activity and specific rate of 1.0 wt% Ru-5NiO/TiO₂ were achieved as 731.3 mmol h^??1 g^??1 and 1030.7 mmol h^?1 g^?1, respectively, which surpassed those of monometallic Ru-based catalysts (1.0 wt% Ru/TiO₂, 1.0 wt% Ru/SiO_2, and 1.6 wt% Ru/C). Moreover, the stability of 1.0 wt% Ru-5NiO/TiO₂ nanocatalyst was sustained for long-term operation (>?360 h) and no leaching of ruthenium was highly acknowledged.

Graphical Abstract

     

Catalytic oxidation of trichloroethylene over TiO2 supported ruthenium catalysts

Different types of TiO₂ (anatase, P25 and rutile) supported ruthenium catalysts were synthesized by wet impregnation and directly reduced in H₂. The distribution characteristics of ruthenium species were thoroughly studied before and after trichloroethylene oxidation. The results show that ruthenium oxide species are very unstable in the anatase phase, but quite stable in the rutile phase of TiO₂. This phenomenon results in different catalytic behaviors for the Ru/TiO₂ catalysts. The Ru/TiO₂ (P25) catalyst has the best catalytic performance among these catalysts. The complete conversion temperature of trichloroethylene is in the temperature range of 260–270 °C.     

Support modification to improve the sulphur tolerance of Ag/Al2O3 for SCR of NOx with propene under lean-burn conditions

Ag/Al₂O₃ catalysts with 1 wt% SiO₂ or TiO₂ doping in alumina support have been prepared by wet impregnation method and tested for sulphur tolerance during the selective catalytic reduction (SCR) of NO_x using propene under lean conditions. Ag/Al₂O₃ showed 44% NO_x conversion at 623 K, which was drastically reduced to 21% when exposed to 20 ppm SO₂. When Al₂O₃ support in Ag/Al₂O₃ was doped with 1 wt% SiO₂ or TiO₂ the NO_x conversion remained constant in presence of SO₂ showing the improved sulphur tolerance of these catalysts. Subsequent water addition does not induce significant deactivation. On the contrary, a slight promotional effect on the activity of NO conversion to nitrogen is observed after Si and Ti incorporation. FTIR study showed the sulphation of silver and aluminum sites of Ag/Al₂O₃ catalysts resulting in the decrease in the formation of reactive intermediate species such as –NCO, which in turn decreases NO_x conversion to N₂. In the case of Ag/Al₂O₃ doped with SiO₂ or TiO₂, formation of silver sulphate and aluminum sulphate was drastically reduced, which was evident in FTIR resulting in remarkable improvement in the sulphur tolerance of Ag/Al₂O₃ catalyst. These catalysts before and after the reaction have been characterized with various techniques (XRD, BET surface area, transmittance FTIR and pyridine adsorption) for physico-chemical properties.     

Physico-Chemical Properties of Cobalt–Ruthenium (10% Co–0.5% Ru) Catalysts Supported on Binary Oxides 8.5%ZrO<Subscript>2</Subscript>/Support (SiO<Subscript>2</Subscript>, Al<Subscript>2</Subscript>O<Subscript>3</Subscript>, TiO<Subscript>2</Subscript>) for Fischer-Tropsch Synthesis

The promotion of Fischer-Tropsch catalysts 10%Co/Al₂O₃, 10%Co/SiO₂, 10%Co/TiO₂ by 0.5% Ru and the modification of supports by 8.5 wt% ZrO₂ have been studied. The following properties: catalyst specific surface area as well as reducibility and dispersion of metallic phase were studied by different techniques: BET, TPR, and H₂ chemisorption. The modification of supports by non-reducible ZrO₂, results in a decrease of cobalt oxide reduction on Al₂O₃ and TiO₂ but not on SiO₂ supports. Additionally the enhancement of cobalt dispersion was found for all catalysts with ZrO₂ modified supports. The impact of Ru promotion is likely due to the stabilization of applied supports, prevention or blockage of interaction between surface Co species and support and an increase in cobalt oxide reducibility to the catalytically active metallic cobalt phase.     

Transient response of catalyst bed temperature in the pulsed reaction of partial oxidation of methane to synthesis gas over supported group VIII metal catalysts

Mechanisms of partial oxidation of methane to synthesis gas were studied using a pulsed reaction technique and temperature jump measurement. Catalyst bed temperatures were directly measured by introducing 1 and 3 ml pulses of a mixture of CH₄ and O₂ (2/1). With Ir, Pt and Ni/TiO₂ catalysts, a sudden temperature increase at the front edge of the catalyst bed was observed upon introduction of the pulse. The synthesis gas production basically proceeded via two-step paths consisting of highly exothermic complete methane oxidation to give H₂O and CO₂, followed by the endothermic reforming of methane with H₂O and CO₂. In contrast, with the Rh and Pd/TiO₂ catalysts, the temperature at the front edge of the catalyst bed decreased upon introduction of the CH₄/O₂ (2/1) pulse and a small increase in the temperature at the rear end was observed. Initially, the endothermic decomposition of CH₄ to H₂ and deposited carbon or CH_x probably took place at the front edge of the catalyst bed, after which the deposited carbon or generated CH_x species would be oxidized into CO_x. When the Ru/TiO₂ catalyst was used, a temperature increase at the front edge of the catalyst bed was observed upon introduction of the 3 ml pulse of CH₄/O₂. In contrast, the temperature drop at the front edge of the catalyst bed was observed for a 1 ml pulse of CH₄/O₂. These results seemed to exhibit two possibilities for a synthesis gas formation route over the Ru/TiO₂ catalyst. The reaction pathway of the partial oxidation of methane with group VIII metal-loaded catalysts depended strongly upon the metal species and reaction conditions.     

Nano-gold supported on Fe2O3: A highly active catalyst for low temperature oxidative destruction of methane green house gas from exhaust/waste gases

A number of nano-gold catalysts were prepared by depositing gold on different metal oxides (viz. Fe₂O₃, Al₂O₃, Co₃O₄, MnO₂, CeO₂, MgO, Ga₂O₃ and TiO₂), using the homogeneous deposition precipitation (HDP) technique. The catalysts were evaluated for their performance in the combustion of methane (1 mol% in air) at different temperatures (300–600 °C) for a GHSV of 51,000 h⁻¹. The supported nano-gold catalysts have been characterized for their gold loading (by ICP) and gold particle size (by TEM/HRTEM or XRD peak broadening). Among these nano-gold catalysts, the Au/Fe₂O₃ (Au loading = 6.1% and Au particle size = 8.5 nm) showed excellent performance. For this catalyst, temperature required for half the methane combustion was 387 °C, which is lower than that required for Pd(1%)/Al₂O₃ (400 °C) and Pt(1%)/Al₂O₃ (500 °C) under identical conditions. A detailed investigation on the influence of space velocity (GHSV = 10,000–100,000 cm³ g⁻¹ h⁻¹) at different temperatures (200–600 °C) on the oxidative destruction of methane over the Au/Fe₂O₃ catalyst has also been carried out. The Au/Fe₂O₃ catalyst prepared by the HDP method showed much higher methane combustion activity than that prepared by the conventional deposition precipitation (DP) method. The XPS analysis showed the presence of Au in the different oxidation states (Au⁰, Au¹⁺ and Au³⁺) in the catalyst.     

Hydrogenolysis of Glycerol to Propanediols Over Highly Active Ru–Re Bimetallic Catalysts

Several supported Ru–Re bimetallic catalysts (Ru–Re/SiO₂, Ru–Re/ZrO₂, Ru–Re/TiO₂, Ru–Re/H-β, Ru–Re/H–ZSM5) and Ru monometallic catalysts (Ru/SiO₂, Ru/ZrO₂, Ru/TiO₂, Ru/H-β, Ru/H–ZSM5) were prepared and their catalytic performances were evaluated in the hydrogenolysis of glycerol to propanediols (1,2-propanediol and 1,3-propanediol) with a batch type reactor (autoclave) under the reaction conditions of 160 °C, 8.0 MPa and 8 h. Compared with Ru monometallic catalysts, the Ru–Re bimetallic catalysts showed much higher activity in the hydrogenolysis of glycerol, and Re exhibited obvious promoting effect on the performance of the catalysts. The supported Ru monometallic catalysts and Ru–Re bimetallic catalysts were characterized by N₂ adsorption/desorption, XRD, TEM-EDX, H₂-TPR and CO chemisorption for obtaining some physicochemical properties of the catalysts, such as specific surface areas, crystal phases, morphologies/microstructure, reduction behaviors and dispersion of Ru metal. The results of XRD and CO chemisorption indicate that the addition of Re component could improve the dispersion of Ru species on supports. The measurements of H₂-TPR revealed that the coexistence of Re and Ru components on supports changed the respective reduction behavior of Re or Ru alone on the supports, indicating the existence of synergistic effect between Ru and Re species on the bimetallic catalysts. The hydrogenolysis of some products (such as 1,2-propanediol, 1,3-propanediol, 1-propanol and 2-propanol) were also examined over Ru and Ru–Re catalysts for evaluating influence of Re–Re on the reaction routes during glycerol hydrogenolysis. The results showed that over Ru–Re catalysts, glycerol was favorable to be converted to 1,2-propanediol, but not favorable to ethylene glycol, while 1,2-propanediol and 1,3-propanediol were favorable to be converted to 1-propanol. The influence of glycerol concentration in its aqueous solution on the catalytic performance was also evaluated over Ru and Ru–Re catalysts.