| Oxidation of styrene was an environmentally-friendly process for the synthesis of styrene oxide. Different by-products were produced depenting on usage of different kinds of catalysts and oxidiants. It was reported that the main products of styrene oxidation, catalyzed by Co2|-zeolite as catalyst, using O2 as oxidant, were styrene oxide and benzaldehyde. Both of them were important intermediates, which were used in wide range fields. Further, there were some other advantages such as high catalytic activity, facile reaction conditions, and low costs, for this reaction system, which makes it deserved for further investigation. As part of the forefront-based of technology research in Henan Province (No.092300410062). On the basis of a small pilot study by Nanjing University of Technology, using the CoX catalysts, which was high activity, high stability, prepared and provide by Nanjing University of Technology, O2 as the oxygen source, to progressively larger study of laboratory of catalytic oxidation of styrene synthesis of styrene oxide and benzaldehyde. There were some aspects of the study were included:analysis of reaction solution of styrene catalyzed oxidation process; progressively larger study of laboratory, including reactor design and conditions of amplification process; the reaction kinetics of the system. Study not only has a certain amount of academic theory, also, provide the basis data for the reaction system to further enlarge and ultimately industrialization.A method for the determination of styrene, styrene oxide and benzaldehyde in reaction solution of styrene catalytic oxidation by GC was developed. N-heptane was used as an internal standard. The samples were well separated on a DB-1 capillary column and detected with FID as a detector. The recoveries of the method were 98%～101.5%, and RSD was less than 2.0%. The detection limits were 2.03×10-3 g/L and 6.11×10-3 g/L, linear range were 0.15～20.85 g/L,0.31～9.24 g/L and 0.25～8.57 g/L for styrene, styrene oxide and benzaldehyde.On the basis of a small pilot study by Nanjing University of Technology, to progressively larger study of laboratory of catalytic oxidation of styrene,50 ml scale experiments were magnified to 100 ml,500 ml and 1000 ml. The distribution of advantages and disadvantages of mass transfer of oxygen was the sensitive factors, affect the styrene conversion, styrene oxide and benzaldehyde selectivity in the experiment. Design a bubble column reactor applicable to this reaction system, examine the main factors that affect the styrene conversion, styrene oxide and benzaldehyde selectivity in the experiment, established better conditions for the amplification process. Under this condition, repeated experiments show that:reaction after 2-3 h, Styrene conversion rate has reached 59.3%, the overall selectivity of Styrene oxide and Benzaldehyde has reached 92.0%, the results will be up to the level of 50 ml scale; reaction after 6 h, Styrene conversion rate can be increased to 80.0%, compared with the Styrene conversion rate 62.5% of 50 ml scale experiments.Study on the apparent kinetics of Catalytic oxidation of Styrene. With the experimental data, the consumption rate equation of styrene can be described as r=-dCA/dt=0.755e-14.57×10-3RTCA.0e-(0.755e-14.57×10-3/RT)t, in which the apparent activation energy was Ea=14.57×10-3 KJ·mol-1, frequency factor was A=0.755 s-1. The generation rate equation of Styrene oxide can be described asr= 1.28e-01915/RTCA.0e-(0755e-0.01457/RT)t, in which the apparent activation energy was=19.15×10-3 KJ·mol-1, frequency factor was 1.28 s-1. And the reliability was verified. The experiment has provided the foundation data, for the further enlarge, pilot, ultimately industrialization and reactor design.
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