Relation between the distribution of platinum, its dispersion, and activity of catalysts prepared by impregnation of activated carbon with chloroplatinic acid solutions

1981 ◽  
Vol 46 (13) ◽  
pp. 3270-3277 ◽  
Author(s):  
Vladimír Machek ◽  
Jiří Hanika ◽  
Karel Sporka ◽  
Vlastimil Růžička ◽  
Jiří Kunz
Keyword(s):  
Activated Carbon ◽  
Liquid Phase ◽  
Uniform Distribution ◽  
Catalyst Activity ◽  
Chloroplatinic Acid ◽  
Acid Solutions ◽  
Liquid Phase Hydrogenation ◽  
Distribution Water

The effect was studied of the solvent of chloroplatinic acid used for impregnation of activated carbon on the distribution and dispersion of platinum and on the catalyst activity. Using different solvents, catalysts were prepared exhibiting either surface platinum distribution (water) or its uniform distribution (ketones). Catalysts with uniform platinum distribution displayed a better stability of the platinum dispersity against sintering. The catalyst activities in liquid phase hydrogenation of 1-octene and of nitrobenzene were related to the platinum dispersity; the results suggest that the hydrogenations of the two substrates are governed by different mechanisms.

scholarly journals Aminated Activated Carbon in Liquid-phase Hydrogenation of Organic Compounds

2020 ◽  
Vol 35 (3) ◽  
pp. 103-110
Author(s):  
N.A. Magdalinova ◽  
◽  
K.M. Puzakova ◽  
M.V. Klyuev ◽  
◽  
...  
Keyword(s):  
Activated Carbon ◽  
Liquid Phase ◽  
Organic Compounds ◽  
Liquid Phase Hydrogenation

Granulated Carbon Nanotubes as the Catalyst Support for Pt for the Hydrogenation of Nitrobenzene

2010 ◽  
Vol 63 (1) ◽  
pp. 131 ◽  
Author(s):  
Shao Jin ◽  
Weizhong Qian ◽  
Yi Liu ◽  
Fei Wei ◽  
Dezeng Wang ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Mass Transfer ◽  
Catalytic Activity ◽  
Activated Carbon ◽  
Liquid Phase ◽  
Transfer Rate ◽  
High Selectivity ◽  
Mass Transfer Rate ◽  
Catalyst Support ◽  
Liquid Phase Hydrogenation

Granulated Pt/carbon nanotubes (CNTs) were found to have a much better catalytic activity in the liquid phase hydrogenation of nitrobenzene than Pt/activated carbon (AC). The granulated CNTs had much larger pores than the AC particles, which gave a faster mass transfer rate of H2 that helped produce aniline with high selectivity.

Preparation of Pt/activated carbon and Pt/alumina catalysts by impregnation with platinum complexes

1983 ◽  
Vol 48 (2) ◽  
pp. 517-526 ◽  
Author(s):  
Vladimír Machek ◽  
Vlastimil Růžička ◽  
Marie Šourková ◽  
Jiří Kunz ◽  
Leoš Janáček
Keyword(s):  
Activated Carbon ◽  
Liquid Phase ◽  
Platinum Complex ◽  
Platinum Complexes ◽  
Nonuniform Distribution ◽  
Platinum Compound ◽  
Chloroplatinic Acid ◽  
Platinum Compounds ◽  
Adsorption Rates ◽  
Alumina Catalysts

Activated carbon and alumina catalysts were prepared by impregnation with solutions of platinum compounds differing substantially in the nature of their interaction with the supports: chloroplatinic acid (dissolved in water or acetone), tetraammineplatinum dichloride, and tetrakis (triphenylphosphine)platinum complex. The relations between the course of impregnation, distribution of platinum across the catalyst grain, and the activity of the catalyst in liquid phase hydrogenations were studied. Lower adsorption rates and amounts of the platinum compound adsorbed on the support bring about a more uniform platinum distribution across the grain. Catalysts with a uniform distribution exhibit higher activities than those with nonuniform distribution. The highest activity was achieved with Pt/alumina catalysts prepared from triphenylphosphine platinum comlex thermally treated in oxygen atmosphere prior to the reduction.

Reaction Pathways and the Role of Solvent in the Hydrogenation of Chloronitrobenzenes

2003 ◽  
Vol 68 (10) ◽  
pp. 1819-1832 ◽  
Author(s):  
Vieroslav Krátky ◽  
Milan Králik ◽  
Alexander Kaszonyi ◽  
Magdaléna Stolcová ◽  
Lubomír Zalibera ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Benzene Ring ◽  
Catalyst Activity ◽  
Reaction Pathways ◽  
Reaction Conditions ◽  
Liquid Phase Hydrogenation ◽  
Role Of Solvent ◽  
Hplc Analyses ◽  
C Nmr

Liquid phase hydrogenation of chloronitrobenzenes to corresponding chloroanilines over Pd on carbon (Pd/C) under mild reaction conditions was studied. On the basis of 1H, 13C NMR, GC-MS and HPLC analyses of reaction mixtures, the reaction pathways were evaluated. The reduction of substrates proceeds via the formation of chloronitrosobenzenes and N-(chlorophenyl)hydroxylamines and mainly results in the formation of the chloroanilines and aniline. Aniline is formed by hydrogenolysis of chlorine (dechlorination) in benzene ring. Other compounds (mono- and disubstituted azobenzenes and azoxybenzenes) were also detected by GS-MS and HPLC (<3 mole %). The used solvent influences the reaction mixture composition and catalyst activity.

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