Catalytic properties of carbon materials for wet oxidation of aniline.
A mesoporous carbon xerogel with a significant amount of oxygen functional groups and a commercial activated carbon, were tested in the catalytic wet air oxidation of aniline at 200 degrees C and 6.9 bar of oxygen partial pressure. Both carbon materials showed high activity in aniline and total organic carbon removal, a clear increase in the removal efficiency relatively to non-catalytic wet air oxidation being observed. The best results in terms of aniline removal were obtained with carbon xerogel, an almost complete aniline conversion after 1h oxidation with high selectivity to non-organic compounds being achieved. The materials were characterized by thermogravimetric analysis, temperature programmed desorption, N(2) adsorption and scanning electron microscopy, in order to relate their performances to the chemical and textural characteristics. It was concluded that the removal efficiency, attributed to both adsorption and catalytic activity, is related to the mesoporous character of the materials and to the presence of specific oxygen containing functional groups at their surface. The effect of catalytic activity was found to be more important in the removal of aniline than the effect of adsorption at the materials surface. The results obtained indicate that mesoporous carbon xerogels are promising catalysts for CWAO processes.
Gomes
Helder T
HT
Laboratório de Catálise e Materiais (LCM), Laboratório Associado LSRE/LCM, Departamento de Engenharia Química, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
Machado
Bruno F
BF
Ribeiro
Andreia
A
Moreira
Ivo
I
Rosário
Márcio
M
Silva
Adrián M T
AM
Figueiredo
José L
JL
Faria
Joaquim L
JL
D000327:Adsorption; D000814:Aniline Compounds / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D060729:Coal Ash; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D052638:Particulate Matter / Q000737:chemistry; D013696:Temperature
D000814:Aniline Compounds; D060729:Coal Ash; D052638:Particulate Matter; D002244:Carbon; D010100:Oxygen