Highly active catalysts for the carbonylation of a variety of substrate materials have been prepared in the form of selenium‐containing ionic liquids. Products from the reactions of [KSeO2(OCH3)] and 1‐alkyl‐3‐methylimidazolium chlorides (see scheme) exhibit surprisingly high activity for the oxidative carbonylation of aniline, even at temperatures as low as 40 °C.
Isothermal vapor-liquid equilibrium data were determined for binary systems of difluoromethane/1,1,1,2tetrafluoroethane (HFC-32/HFC-134a), difluoromethane/pentafluoroethane (HFC-32/HFC-125), difluoromethane/1,1,1-trifluoroethane (HFC-32/HFC-143a), and difluoromethane/1,1-difluoroethane (HFC-32/ HFC-152a). The vapor and liquid compositions and pressures were measured in a circulation-type apparatus at 303.15 K and 323.15 K. The experimental data were compared with literature results and correlated with the Canahan-Starling-De Santis equation of state within the uncertainty of (1.0%.
GA, PTBC, and TBHQ, regeneration was tried but no measurable rate of absorption of pure oxygen was observed.Thus, it seems unlikely on the basis of the above experiments as well as the chemistry of these oxidation reactions that a regenerative process for obtaining pure oxygen is possible with these PHBs. However, for removal of oxygen at very low levels, these may have some practical applications.
ConclusionsThe absorption of oxygen in aqueous alkaline solutions of PTBC and TBHQ, under certain conditions, was found to conform to the fast pseudo-first-order reaction regime.The reaction was found to be first order in oxygen and PTBC or TBHQ. The absorption of oxygen in aqueous alkaline solutions of PG, GA, and TMHQ was found to conform to the instantaneous reaction regime. However, for very low alkali to PHB ratios, under certain conditions for PG, the absorption conformed to the pseudo-first-order reaction regime. The absorption of oxygen at very low
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