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Ni and Cu mono‐ and bimetallic catalysts modified with various types of acid oxides MOx (M=Mo, V, W, and Re) were tested for the hydrogenolysis of glycidol as an alternative route to the hydrogenolysis of glycerol to obtain 1,3‐propanediol (1,3‐PrD). Characterization results revealed that the presence of modifiers affected the dispersion and reducibility of the NiO particles and the strength and amount of acid sites. Among the modifiers tested, Re led to the highest activity, a high propanediols selectivity, and the highest 1,3‐PrD/1,2‐propanediol (1,2‐PrD) ratio. The Ni‐Cu/Re ratio was optimized to improve the catalytic activity. The best catalytic result, with a 46 % 1,3‐PrD yield and a 1,3‐PrD/1,2‐PrD ratio of 1.24, was obtained if the monometallic Ni catalyst at 40 wt % loading and modified with 7 wt % Re was used at 393 K and 5 MPa H2 pressure after 4 h of reaction. The overall 1,3‐PrD yield starting from glycerol and assuming a two‐step synthesis (glycerol→glycidol→1,3‐PrD) and a yield of 78 % for the first step would be 36 %. This 1,3‐PD yield is the highest for a reaction catalyzed by a non‐noble metal and is comparable to the direct hydrogenolysis of glycerol using noble metal catalysts at a longer time and a high H2 pressure.

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H-and Na-saponite supports have been prepared by several synthesis approaches. 5% Cu/saponite catalysts have been prepared and tested for soot combustion in a NO x + O 2 + N 2 gas flow and with soot and catalyst mixed in loose contact mode. XRD, FT-IR, N 2 adsorption and TEM characterization results revealed that the use of either surfactant or microwaves during the synthesis led to delamination of the saponite support, yielding high surface area and small crystallite size materials. The degree of delamination affected further copper oxide dispersion and soot combustion capacity of the Cu/saponite catalysts. All Cu/saponite catalysts were active for soot combustion, and the NO 2 -assisted mechanism seemed to prevail. The best activity was achieved with copper oxide supported on a Na-saponite prepared at pH 13 and with surfactant. This best activity was attributed to the efficient copper oxide dispersion on the high surface area delaminated saponite (603 m 2 g −1 ) and to the presence of Na. Copper oxide reduction in H 2 -TPR experiments occurred at lower temperature for the Na-containing catalysts than for the H-containing counterparts, and all Cu/Na-saponite catalysts were more active for soot combustion than the corresponding Cu/H-saponite catalysts.Catal. Sci. Technol. This journal is

Two microporous hectorites were prepared by conventional and microwave heating, and a delaminated mesoporous hectorite by an ultrasound-assisted synthesis, and these three hectorites were impregnated with copper. The characterization techniques used were XRD, N 2 adsorption, TEM and H 2 reduction after selective surface copper oxidation by N 2 O (to determine copper dispersion). The catalytic activity for soot combustion of both the copper-free and the copper-containing hectorites was tested under a gas mixture of 500 ppm NOx/5%O 2 /N 2 (and 5% O 2 /N 2 in particular cases), evaluating their stability through three consecutive soot combustion experiments. The delaminated hectorite achieved the highest surface area (353 m 2 /g) and also the highest dispersion of copper, and this copper-containing catalyst was the most active for soot combustion among those prepared and tested in this study. It has been also concluded that the Cu/hectorite-catalyzed soot combustion mechanism is based on the activation of the O 2 molecule and not on the NO 2-assisted soot combustion.

The effect of copper on various acid saponite supported Ni-Cu bimetallic catalysts, prepared with different Ni:Cu ratios, was studied for the liquid phase hydrogenolysis of glycidol on a batch reactor...

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