Pore, diameter, supports/catalysts after

Table 3. presents the abatement results of simulated wastewater succinic acid solution with different catalysts in CWO process. The reactions were carried out in an autoclave under the same reaction conditions. The content of Ru in the catalysts is approximately 2%. Among the tested catalyst, Ru/TiOj. S has the highest COD removal rate. This may be due to the contribution of surface treatment on the support. The specific area, pore volume and average pore diameter are enlarged after the treatment, resulting in the Ru concentration increase on the surface of the support and accelerating the reaction speed. Further study on the Ru/TiOjiS is still underway, and new results will be reported elsewhere. 

Polyethylene. Low pressure polymerization of ethylene produced in the Phillips process utilizes a catalyst comprised of 0.5—1.0 wt % chromium (VI) on siUca or siUca-alumina with pore diameter in the range 5—20 nanometers. In a typical catalyst preparation, the support in powder form is impregnated with an aqueous solution of a chromium salt and dried, after which it is heated at 500—600°C in fluid-bed-type operation driven with dry air. The activated catalyst is moisture sensitive and usually is stored under dry nitrogen (85). 

BET Surface Area, Pore Volume, and Average Pore Diameter of the Supports and Catalysts after Calcination at 623 K... 

An ionic liquid supported Pd catalyst, [NB4MPy ][BF4 ]Pd (acac)/AC with a nominal Pd loading of 0.3 wt.% was prepared and characterized in this work. According to the XPS analysis Pd was not in reduced state after the reduction at 100°C - 120°C. The specific surface area, micropore volume and the pore diameter decreased after introducing ionic liquid into support, by 32%, 32% and, 18% respectively, compared to the active carbon support. SEM images from a ftesh and a spent [NB4MPy ][BF4 ]Pd(acac)/AC catalysts revealed that... 

Fig. 3 depicts the N2 adsorption-desorption isotherms (A) and pore size distribution (B) of the samples. The shape of the isotherms (Fig. 3A) and the pore sizes did not change significantly (Table 1), meaning that material kept its mesoporous structure after introduction of the ceria. The pore diameters of the support and the gold loaded catalysts, both calcined at 400 °C, are practically... 

Table 1. BET surface area, mean pore diameter, and pore volume for the supports and catalysts after calcination. For the nitrogen sorption data, the experimental error ( 2ff) is 5 m /g for the surface areas, 0.2 nm for the mean pore diameters, and 0.02 cm /g for the pore volumes.

Catalyst preparation. Chloroplatinic acid, in such amounts as to obtain the desired concentration of Pt in the catalysts, was added to previously prepared w/o microemulsions. Two types of catalytic supports, y-alumina in the form of full pellets (diameter 5 mm) and 0-alumina in the form of hollow pellets (diameter 5 mm, hole 2 mm), both manufactured in Chemopetrol Litvinov, Czech Republic, were chosen for catalysts preparation. After calcination at 500 °C y-alumina had Sbet=166 m /g, pore volume 0.459 ml/g, mean pore radius 7.0 nm and water absorption capacity 40 %. After calcination at 900 °C 0-alumina showed Sbet=145 m /g, pore volume 0.445 ml/g, mean pore radius 8.1 nm and water absorption capacity 50 %. The catalysts with 0.3 and 0.1 wt. % Pt were prepared by impregnation with HaPtCle water solutions (denoted as I) or Pt microemulsions (denoted as M). The catalysts were dried 2 h at 120-160°C and calcined 2 h in air at 550 °C. Characterization of microemulsions... 

Various promoted Ni/MgO catalysts have been prepared by multiple successive impregnation of the MgO support. Tlie support used, which was calcined at 1450°C, had the following characteristics macroporous spherical granules having diameter of about 20 mm, BET surface area of 0.25 m and specific pore volume of 0.145 cmV -Aqueous solutions of Ni-nitrate and nitrate of the corresponding promoter, with atomic ratio 10 1, respectively, were used. All the impregnation steps were performed at 25°C, with the ratio of solution volume to support mass of 3 cmV. and the solution/support contact time of 30 min. After each impregnation the catalyst precursors were subsequently dried at 110°C for Ih and calcined at 400°C for 2h to convert nitrate salts onto oxides. 

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