33627-01-9Relevant academic research and scientific papers
Studies on calcined cow bone and pyrolyzed wood, suitable supports for immobilizing hybrid nano particles of Co-Mn as new catalysts for oxidation of 2,6-diisopropyl naphthalene
Mardani Ghahfarrokhi, Atefeh,Moshiri, Parisa,Ghiaci, Mehran
, p. 51 - 58 (2013/06/27)
Catalytic oxidation of 2,6-diisopropylnaphthalene (2,6-DIPN) to 2,6-naphthalene dicarboxylic acid (2,6-NDCA) was studied with two new catalysts prepared by immobilization of Co/Mn nano-hybrid particles over calcined cow bone, and pyrolyzed wood. The catalysts have the advantage of very cheap supports, and easy catalyst recovery. The effects of Co/Mn atomic ratio, reaction time and temperature, oxygen pressure, amount of catalyst, and the support on the conversion of 2,6-DIPN and product/intermediate yields were investigated. There was an interesting synergistic effect of cobalt and manganese catalysts. The maximum product (2,6-NDCA) yield was 100%, obtained at a Co/Mn atomic ratio of 10 supported on pyrolyzed wood. Lower cobalt concentration resulted the lower 2,6-NDCA yield, which was ascribed to the intermediate products formation. The catalysts were characterized in detail by SEM/EDS, BET surface area, and TEM measurements. Transmission electron microscopy (TEM) measurements indicated nanoparticles (diameter of about 2-5 nm) on the surface of the supports.
Formation of 2,6-Naphthalenedicarboxylic Acid by the Co-Mn-Br-Catalyzed Autoxidation of 2,6-Diethylnaphthalene in Acetic Acid
Kamiya, Yoshio,Hama, Takashi,Kijima, Ichiro
, p. 204 - 210 (2007/10/02)
In order to elucidate the reaction mechanism and the optimum reaction conditions for the formation of 2,6-naphthalenedicarboxylic acid (NDCA), the Co(OAc)2-Mn(OAc)2-NaBr-catalyzed oxidation of 2,6-diethylnaphthalene by molecular oxygen was carried out in acetic acid.The oxidation of the ethyl groups to carboxyl groups proceeded mainly via groups and partly via 1-hydroxyethyl and 1-acetoxyethyl groups.A synergistic catalytic effect due to Co and Mn acetates was observed not only on the rate of oxidation but also on the selective formation of NDCA.The rate of oxidation was strongly retarded at higher concentrations of the substrate, showing that the naphthalene nucleus terminates the chain reaction step of the oxidation.A high concentration of metal catalyst resulted in an increase of acetoxyethylnaphthoic acid.At the optimum reaction conditions, a nearly 90percent yield of NDCA was obtained along with small amounts of substituted naphthoic and trimellitic acids.The differences in the yield of NDCA from 2,6-dimethyl, 2,6-diethyl, and 2,6-diisopropylnaphthalenes were compared under similar reaction conditions and are discussed.
