| The thesis was based on the hydrolysis of cinnamaldehyde with NaOH. The effects of the two substances on the reaction system and the yield of benzaldehyde were investigated through changing the alkaline environment with LiOH and activated carbon. The effects of activated carbon on the hydrolysis reaction order and activation energy were also studied. What’s more, the adsorption properties of activated carbon to the main components of the reaction system were reseached and the reaction process was analyzed preliminarily. The main research results were showing as follows:(1) Firstly, GC and UV detection were used in the hydrolysis system of cinnamaldehyde with NaOH and LiOH,on the base of which the main components of the reaction system were qualitative and quantitative analyzed. It showed that LiOH system was mainly composed of benzaldehyde, cinnamaldehyde, and 5-phenyl-2,4-pentadienal(PPDA) component,which similar to NaOH system. Between the two alkaline hydrolysis systems the concentration of benzaldehyde, cinnam- aldehyde and PPDA in the reaction solution changed significantly in the first 30 min changed more slowly after 30 min. The concentration of cinnamaldehyde reduced with time, while the concentration of benzaldehyde and PPDA increased. The latter changed more slowly.(2) The influence of activated carbon to different type of alkaline hydrolysis system were studied. The reactants of different time and the steam distillation of the distillate were detected. The results showed that:There were not any new substance produced with activated carbon involved in the reaction. To some extent, activated carbon improved the conversion of cinnamaldehyde in NaOH and LiOH system.(3) By researching the activated carbon to synthesis of benzaldehyde optimization, the activated kinds, amount, the time of the activated carbon were added and the temperature of the reaction system were studied. And the optimum reaction and conditions of alkaline hydrolysis as follows:The effect that analysis pure activated carbon powder improved the yield of benzaldehyde was the best, and at the beginning of the reaction, a small amount of activated carbon yield the maximum NaOH benzaldehyde system which increased from 50.2% to 59.5 %, and LiOH yield of benzaldehyde system which increased from 54.7% to 63.2 %, the best ratio of quality institute experiment election cinnamaldehyde and AR activated carbon powder was 60 : 1, the impact of activated charcoal on the reaction rate decreases with increasing temperature,80℃ is the highest yield of benzaldehyde.(4) The reaction kinetics of the different systems were carried out. Activated carbon had an influence on the NaOH and LiOH as follow:The activation energy of the hydrolysis reaction of NaOH decreased from 52.7 down to 49.3 kJ·mol-1, LiOH activation energy decreased from the hydrolysis reaction 51.8 to 47.0 kJ·mol-1.(5) Finally, by examining the adsorption properties of activated carbon cinnamicaldehyde and benzaldehyde mixed solution and carried out: Using the Langmuir adsorption kinetics rate equations can describe the cinnamaldehyde and benzaldehyde behavior better. Activated carbon adsorption of cinnamaldehyde and benzaldehyde constants were 1.2842 h-1 and 1.4262 h-1. Activated carbon cinnamic aldehyde and benzaldehyde adsorption kinetics can be well described by the quasi-two models. |
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