Study On The Ammoximation Of 2-butanone Over TS-1

2-Butanone oxime is an excellent fine chemical. Due to its low toxicity, lowenvironmental pollution and high deoxidization effect, it can be widely used ascorrosion inhibitor and passivator in boiler passivation solution of fire power plantinstead of N2H4. The TS-1 is a kind of prospective and benign catalyst. Theammoximation of 2-butanone to 2-butanone oxime with hydrogen peroxide andammonia over TS-1 has distinct advantages, such as fast reaction rate, moderateconditions, high selectivity to 2-butanone oxime and no pollution during theproduction process. In this thesis, the reaction conditions, catalytic reaction pathwayand the intrinsic kinetics of 2-butanone ammoximation with hydrogen peroxide overTS-1 have been studied.Firstly, the effects of solvent, reaction temperature, molar ratio of ammonia tobutanone, adding mode of H2O2 on the conversion of 2-butanone and the selectivity of2-butanone oxime were investigated. The results indicated that 2-butanone oxime canbe synthesized through ammoximation of 2-butanone over TS-1 at mild conditions,and the conversion of 2-butanone and the selectivity of 2-butanone oxime can reach99.12% and 99.99%, respectively. The optimized reaction conditions were as follow:the ratio of ammonia to butanone above 2.15, reaction temperature at 70oC, and H2O2added continuously.Secondly, according to the reaction results obtained in a two-step reaction, it wasto confirm that this mechanism involves as key step the formation of hydroxylamine,formed by the reaction between ammonia and hydrogen peroxide on titanium centres.In the second step this intermediate reacts in the homogeneous phase with 2-butanoneto give the oxime. The results showed that oximation of 2-butanone was outside TS-1with hydroxylamine. Furthermore, the part of hydroxylamine formed in oxidation ofNH3 by H2O2 did decompose appreciably during the diffusion out of the pores of TS-1,results in the decreasing the selectivity to 2-butanone oxime.Finally, the intrinsic kinetics of ammoximation of 2-butanone with hydrogenperoxide catalyzed TS-1 was studied. The kinetics model based on the catalyticreaction pathway and regressed by means of correlating the experimental data wasobtained. The kinetics equation of 2-butanone ammoximation with hydrogen wasfollows:r₁=9.573×10⁷×exp (-4.382×10⁴/RT) ×C_NH3^1.2375×C_H2O2^0.4894 ...