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Notes: Abstract The derivatives of cyano complex compounds of iron, cobalt and nickel with bifunctional phosphonium-cations were prepared and investigated. In the case of iron and cobalt the phosphonium—hydrogen derivatives can be produced too beside those of the phosphonium-complexes. The thermal decomposition of the compounds was examined by the derivatographic method. The υCN and υNO stretching frequencies of the complexes were compared with the similar frequencies in those of the alkaline cyano complexes and their corresponding free acids. The thermal decomposition of phosphonium—hydrogen—cyanometallates leads to coordinatively unsaturated intermediates which can be prepared.

Notes: Abstract Hydrolysis of triolein in AOT/isooctane reversed micelles by an sn-1,3-regioselective and a non-selective lipase were studied. Kinetics of the multistep reaction: decomposition of tri-, di- and monoacylglycerols and production of fatty acid were investigated separately. All the reactions was found to obey the Michaelis-Menten model and the apparent parameters (Michaelis-constants (Km) and maximal reaction rates (Vmax)) were determined both for non-selective and regioselective preparations.

Notes: Abstract Hydrolysis of olive oil into fatty acids by lipase in a flat membrane module is reported. Lipase was immobilized by adsorption onto a hydrophilic cellulose acetate membrane. Hydrolysis was carried out by circulating pure olive on the enzyme side of the membrane and water phase on the other side. Conversion reached 85 % after 50 hours reaction time.

Notes: Experiments with propane-ethylene mixtures in the temperature range 760-830 K resulted in refinement of the role of ethylene inhibition in the decomposition of propane. The source of the rate-reducing effect of ethylene is the reaction This replaces the decomposition chains more slowly by means of the reactions than H-atoms do by direct H-abstraction from propane. Analysis of the ratios of the product formation rates showed that the selectivity of the ethyl radical for the abstraction of hydrogen of different bond strengths from propane was practically the same as that of the H-atom. The ratio of the rate constants of hydrogen addition to ethylene and methyl-hydrogen abstraction from propane by the H-atom (3) was determined \documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{k_3 }}{{k_8 }} = 10^{5.89 \pm 0.05} \exp ( - 30.8 \pm 1.1{\rm kJ mol}^{{\rm - 1}} /RT) $$\end{document} as was that of the decomposition and the similar H-abstraction of the ethyl radical \documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{k_3 }}{{k_8 }} = 10^{5.11 \pm 0.61} \exp ( - 129 \pm 10{\rm kJ mol}^{{\rm - 1}} /RT){\rm mol}^{{\rm - 1}} {\rm dm}^{\rm 3}. $$\end{document}Interpretation of the influence of ethylene required the completion of the mechanism with further initiation of the reaction besides termination via ethyl radicals.

Notes: On the basis of the thermal decomposition of mixtures of propylene and propane with molar ratios of 0.0-0.33 in the temperature range 779-812K, the influencing functions describing the inhibition by propylene of the decomposition of propane were determined. The rate-reducing effect is explained mainly by the reactions \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 3} {\rm H}_{\rm 6} + {}^.{\rm R} \longrightarrow {}^.{\rm C}_{\rm 3} {\rm H}_{\rm 5} + RH $$\end{document} (in which .R = .H, .CH3 and 2-Ċ3H7) and also by the addition reactions \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 3} {\rm H}_{\rm 6} + {}^.{\rm H} \to 1 - {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ \to 2 - {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7}. $$\end{document} It was established that the bulk of the allyl radicals formed \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 3} {\rm H}_{\rm 8} + {}^.{\rm C}_{\rm 3} {\rm H}_{\rm 5} \to 1 - {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7} + {\rm C}_{\rm 3} {\rm H}_{\rm 6} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ \to 2 - {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7} + {\rm C}_{\rm 3} {\rm H}_{\rm 6} $$\end{document} participate in the chain step, but, due to their lower reactivity, they restore the decomposition chain more slowly than the original radicals do.From the characteristic change in the ratio υCH4/υH2, the rate ratios of hydrogenabstraction reaction by radicals from propylene and propane could be determined. In these reactions there was no significant difference between the selectivities of the radicals. For an interpretation of the changes, the decomposition mechanism must be completed with the reaction \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 3} {\rm H}_{\rm 6} + 2 - {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7} \to 1 - {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7} + {\rm C}_{\rm 3} {\rm H}_{\rm 6}. $$\end{document}Evaluation of the influencing curves revealed that the initiation reactions \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 3} {\rm H}_{\rm 6} + {\rm C}_{\rm 3} {\rm H}_{\rm 6} \to {}^.{\rm C}_{\rm 3} {\rm H}_{\rm 5} + {}^.{\rm C}_{\rm 3} {\rm H}_{\rm 7} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 3} {\rm H}_{\rm 8} + {\rm C}_{\rm 3} {\rm H}_{\rm 6} \to {}^.{\rm C}_{\rm 3} {\rm H}_{\rm 7} + {}^.{\rm C}_{\rm 3} {\rm H}_{\rm 7} $$\end{document} must be taken into account.By parameter estimation we have determined the rate ratios characterizing the above initiation reactions, the unimolecular decomposition of propane, hydrogen abstraction by radicals from propane and propylene, intermolecular isomerization of the 2-propyl radical via propane and propylene, and abstraction of propane hydrogens by the ethyl and methyl radicals; these are given in Tables II.

Notes: Study of the thermal decomposition of propane at very low conversions in the temperature range 760-830 K led to refinement of the mechanism of the reaction.The quotient VCH4 + C2H4/VH2 + C3H6 characterizing the two decomposition routes connected with the 1- and 2-propyl radicals proved to depend linearly on the initial propane concentration. This suggested the occurrence of intermolecular radical isomerization: in competition with decomposition of the 2-propyl radical: The linearity led to the conclusion that the selectivity of H-abstraction from the methyl and methylene groups by the methyl radical is practically the same as that by the H atom. The temperature-dependence of this selectivity ( μ = kCH3/kCH2) was given by\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm \mu = }\frac{{k_3 }}{{k_4 }} = \frac{{k_1 }}{{k_2 }} = 10^{0.26 \pm 0.03} \exp ( - 7.24 \pm 0.45{\rm kJ mol}^{{\rm - 1}} /RT). $$\end{document} Further evaluation of the dependence gave the Arrhenius representation \documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{k_7 }}{{k_6 }} = 10^{ - 5.97 \pm 0.03} \exp (115 \pm 5.1{\rm kJ mol}^{{\rm - 1}} /RT){\rm mol}^{{\rm - 1}} {\rm dm}^{\rm 3} $$\end{document} for the ratio of the rate coefficients of the above isomerization and decomposition reactions.Steady-state treatment resulted in the rate equation of the process, comparison of which with measurements gave further Arrhenius dependences.

Notes: Conditions of applicability of quasi-steady-state kinetic treatment have been investigated with respect to the explanation of the decomposition of propane and the influence of ethylene on this.From the measured rate of accumulation of ethane and from the relations between the kinetic equations describing product formation, the rate parameters of the initiation reactions were determined, for which the temperature-dependences \documentclass{article}\pagestyle{empty}\begin{document}$$ k_i = 10^{17,05 \pm 0.99} \exp ( - 356 \pm 11{\rm kJmol}^{{\rm - 1}} /RT)s^{ - 1} $$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$$ k_{ie} = 10^{12.0 \pm 0.99} \exp ( - 225 \pm 15{\rm kJmol}^{{\rm - 1}} /RT){\rm mol}^{{\rm - 1}} {\rm dm}^{\rm 3} s^{ - 1} $$\end{document} were found.In the decomposition of propane under the examined conditions, the chain length exceeds 500. In response to ethylene the chain length significantly decreases, but even in this case the decomposition chains are long enough for it to be assumed that the ratios of radical concentrations are governed by the propagation steps.Calculations demonstrated that the actual radical concentration during a sufficiently short induction period approximates to the stationary concentration, so that it does not seriously affect the accuracy of the kinetic treatment.

Notes: The thermal decomposition of butene-2-cis at low conversion and its effect on the pyrolysis of propane have been studied in the temperature range 779-812 K.It was established that 2-butene decomposes in a long-chain process, with the chain cycle \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - C}_{\rm 4} {\rm H}_{\rm 8} + {}^.{\rm CH}_{\rm 3} \to {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 7} + {\rm CH}_{\rm 4} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - C}_{\rm 4} {\rm H}_{\rm 8} + {}^.{\rm CH}_{\rm 3} \to {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 7} + {\rm CH}_{\rm 4} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - C}_{\rm 4} {\rm H}_{\rm 8} + {}^.{\rm CH}_{\rm 3} \to {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 7} + {\rm CH}_{\rm 4} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 7} \to {}^.{\rm H} + 1,3 - {\rm C}_{\rm 4} {\rm H}_{\rm 6} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - C}_{\rm 4} {\rm H}_{\rm 8} + {}^.{\rm H} \to {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 7} + {\rm H}_{\rm 2} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ \to 2 - {\rm \dot C}_{\rm 4} {\rm H}_{\rm 9} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - C}_{\rm 4} {\rm H}_{\rm 8} \to + 1,3 - {\rm C}_{\rm 3} {\rm H}_{\rm 6} + {\rm H}_{\rm 2} $$\end{document}(Besides the radical path, the molecular reaction can also play a role in the formation of the products.)The thermal decomposition of propane is considerably inhibited by 2-butene, which can be explained by the fact that the less reactive radicals formed in the reactions between the olefin and the chain-carrying radicals regenerate the chain cycle more slowly than the original radicals in the above chain cycle or in the reactions \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm C}_{\rm 3} {\rm H}_{\rm 8} + {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 7} \to 1 - {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7} + {\rm C}_{\rm 4} {\rm H}_{\rm 8} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ \to 2 - {\rm \dot C}_{\rm 4} {\rm H}_{\rm 7} + {\rm C}_{\rm 3} {\rm H}_{\rm 8} $$\end{document}The reactions of the 2-propyl radical \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - \dot C}_{\rm 3} {\rm H}_{\rm 7} + 2 - {\rm C}_{\rm 4} {\rm H}_{\rm 8} \to {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 7} + {\rm C}_{\rm 3} {\rm H}_{\rm 8} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ \to 2 - {\rm \dot C}_{\rm 4} {\rm H}_{\rm 9} + {\rm C}_{\rm 3} {\rm H}_{\rm 6} $$\end{document} are further initiation steps. The ratios of the rate coefficients of the elementary steps of the decomposition (Table III) have been determined via the ratios of the products.Estimation of the radical concentrations indicated that only the methyl, 2-propyl and methylallyl radicals are of importance in the chain termination.On the basis of the inhibition-influenced curves, the role of the bimolecular initiation steps. \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - C}_{\rm 4} {\rm H}_{\rm 8} + {\rm C}_{\rm 3} {\rm H}_{\rm 8} \to {\rm \dot C}_{\rm 4} {\rm H}_{\rm 9} + {\rm \dot C}_{\rm 3} {\rm H}_{\rm 7} $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm 2 - C}_{\rm 4} {\rm H}_{\rm 8} + 2 - {\rm C}_{\rm 4} {\rm H}_{\rm 8} \to {}^.{\rm C}_{\rm 4} {\rm H}_{\rm 9} + {\rm C}_{\rm 4} {\rm H}_{\rm 7} $$\end{document} could be clarified in the presence of 2-butene.