Selective oxidation of styrene to acetophenone over supported Au–Pd catalyst with hydrogen peroxide in supercritical carbon dioxide

2007 ◽  
Vol 9 (12) ◽  
pp. 1352 ◽  
Author(s):  
Xueguang Wang ◽  
Natarajan S. Venkataramanan ◽  
Hajime Kawanami ◽  
Yutaka Ikushima
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Peroxide ◽  
Supercritical Carbon Dioxide ◽  
Selective Oxidation ◽  
Pd Catalyst ◽  
Supercritical Carbon

scholarly journals Gold catalysed selective oxidation of alcohols in supercritical carbon dioxide

2007 ◽  
Vol 44 (1-2) ◽  
pp. 285-292 ◽  
Author(s):  
Bertram Kimmerle ◽  
Jan-Dierk Grunwaldt ◽  
Alfons Baiker
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Selective Oxidation ◽  
Oxidation Of Alcohols ◽  
Supercritical Carbon

Selective oxidation of cyclohexane in supercritical carbon dioxide over CoAPO-5 molecular sieves

2005 ◽  
Vol 110 (3-4) ◽  
pp. 351-356 ◽  
Author(s):  
Ruizhen Zhang ◽  
Zhangfeng Qin ◽  
Mei Dong ◽  
Guofu Wang ◽  
Jianguo Wang
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Selective Oxidation ◽  
Molecular Sieves ◽  
Supercritical Carbon

Selective oxidation of cyclohexane in supercritical carbon dioxide

2007 ◽  
Vol 113 (3-4) ◽  
pp. 115-119 ◽  
Author(s):  
K. M. Kerry Yu ◽  
A. Abutaki ◽  
Y. Zhou ◽  
B. Yue ◽  
H. Y. He ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Selective Oxidation ◽  
Supercritical Carbon

Selective Oxidation in Supercritical Carbon Dioxide Using Clean Oxidants

2000 ◽  
Vol 39 (12) ◽  
pp. 4858-4864 ◽  
Author(s):  
Endalkachew Sahle-Demessie ◽  
Michael A. Gonzalez ◽  
Julius Enriquez ◽  
Qiuming Zhao
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Selective Oxidation ◽  
Supercritical Carbon

Hydrogen peroxide and supercritical carbon dioxide: a new bleaching stage for Eucalyptus kraft-O2 pulps

Holzforschung ◽  
2011 ◽  
Vol 65 (3) ◽  
Author(s):  
Roberta Pacheco Francisco ◽  
Jorge Luiz Colodette ◽  
Antonio Aprigio da Silva Curvelo
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Peroxide ◽  
Supercritical Carbon Dioxide ◽  
Kraft Pulp ◽  
Poor Performance ◽  
Kappa Number ◽  
Elemental Chlorine ◽  
Chlorine Gas ◽  
Hexenuronic Acid ◽  
Supercritical Carbon

Abstract Kraft pulp is currently bleached largely by the elemental chlorine free (ECF) technology with oxygen, chlorine dioxide, and hydrogen as active agents. This technology brought about significant environmental improvements in relation to standard processes based on chlorine gas and hypochlorite, but there is still need for further improvements. This study presents a novel environmentally friendly bleaching stage – the so-called ‘hydrogen peroxide in supercritical carbon dioxide’, P(SC-CO2) – that can be adapted to current ECF bleaching processes, with preference in cases where hydrogen peroxide is already used. In this study, the P(SC-CO2) stage was evaluated as a replacement to the last peroxide stage of the D(EP)DP bleaching sequence and to the first peroxide stage of the D(EP)DP sequence, for an oxygen delignified eucalypt kraft-O2 pulp. The P(SC-CO2) stage was run with 0.5% hydrogen peroxide, at 15% consistency, 70°C, and 73 bar. The reaction time was 30 min. The performances of regular P stages and the new P(SC-CO2) stage were compared. Promising results were observed with the DEP(SC-CO2)DP sequence; the P(SC-CO2) decreased kappa number from 2.7 to 2.1, and the hexenuronic acid groups from 17.0 to 12.4 mmol kg-1. The P(SC-CO2) stage showed poor performance when applied in the D(EP)DP(SC-CO2) sequence. It is concluded that the process presents potential but requires further optimization to improve selectivity and efficiency.

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