US EPA

7755020 

Journal Article 

Cis-trans Isomerism at o-xylene and p-xylene Hydrogenation on the Ni/Al2O3-SiO2 Catalyst 

Juganaru, T; Bombos, D; Vasilievici, G 

2013 

1 

Revista de Chimie
ISSN: 0034-7752
EISSN: 2668-8212 

Syscom 18 SRL 

BUCHAREST 

64 

4 

442-444 

English 

WOS:000318326600020 

Hydrogenation of o-xylene and p-xylene to 1,2-dimetikiclohexan, and 1,4-dimetilciclohexan was performed using an industrial type catalyst Ni/Al 2O3 SiO2. Experiments were performed on a laboratory installation at a pressure of 10 bar, with a weight hourly space velocities of aromatic component (WHSV) of 0.2 hi and a molar ratio hydrogen / aromatic component aromatic of 10; as raw materials where used the synthetic mixtures of o-xylene, p-xylene and toluene diluted in n-hexane. Temperature varied in the range 60-150°C. Experimental results show a change of cistrans isomers, with a maximum around the temperature of 100 °C. This report is subunitary for p-xylene hydrogenation and above par for o-xylene hydrogenation. This is probably due to the position of methyl groups in aromatic compound molecules, respectively of steric effect of these groups and hydrogenation mechanism type, "roll over". 

catalyst; hydrogenation; support acidity; xylene; isomerism