Study On Synthsis Of Cinnamic Acid From Styrene And Carbon Tetrachloride

The cinnamic acid has been synthesized through the addition andelimination hydrolysis reaction with styrene and carbon tetrachloride as theraw materials. The influence of reaction temperature, reaction time,reactant ratio, the catalyst type and consumption has been studied.In the first step, with cuprous chloride and diethylamine as the catalystsystem, the optimum conditions were: temperature 70~75℃, reaction time6h, reactant molar ratio 1:2, the content of catalyst 5%. The yield reached91.0%.A study of preparing the catalyst has been carried out. The catalystcarrier and the active component has been screened. After the comparisonof the influence factors such as load conditions, the amount of activecomponent etc., a better catalyst has been prepared by dry-mixing methodwith the active component of 10% to 20%. The yield was up to 95% when the reaction was carried out at 70 after 5h. The yield can still reach 80%after being applied for three times.In the second step of elimination hydrolysis reaction, the yields arevaried when the different catalysts were used. Seven systems were studied:acetic acid-ferric chloride system, sulfuric acid-p-toluenesulfonic acidsyetem, acetate acid-zinc sulphate system, acetic acid-phosphoric acidsystem, acetic acid-sulfuric acid system, acetic acid-zinc chloride andacetic acid-ferric sulphate system. The result showed that acetate acid-zincsulphate represented the best catalytic effect. The optimum conditions were:reaction time 12h, the catalyst content 13.3%, acetic acid / intermediate =1~1.3. The yield can reach 91.2%.The kinetics of addition reaction also have been studied. A dynamicmodel has been established:By calculating the experimental data through the Polymath, it obtainedthat the control step of dissociative adsorptionˇs activation energy was111kJ/mol. The kinetic equation was:Fitted with 50 sets of data, the R2 was 0.93, the error of the parameters inthe 95% confidence interval was less than 1.8%.The power function equation was also raised: By calculating the experimental data through the Polymath, it obtainedthe power function equation as follows:Fitted with 48 sets of data, the R2 was 0.93, the error of the parameters inthe 95% confidence interval was less than 1.5%. The total value of theactivation energy was 108kJ/mol and it was similar with the documents.Kinetic equation was better to explain the reaction process, the powerfunction equation was better to explain the effect of reagent concentrationand temperature on the experiment. The results of the two models agreewell with experimental data. The model posed was reliable and reasonable,and can be a reference for project development.