A reaction regarding the preparation of sodium alcohols
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The company is prepared from a reaction involving sodium alcoholate. React under reflux conditions. The molar ratio of alcohol to metallic sodium is 2:1. I believe the reaction rate is independent of the backflow volume, and it is necessary for the plant operators to control the backflow volume. Excessive backflow will only result in wasted steam. However, the workers in the workshop use a high amount of steam and carry out the reaction with a large amount of reflux, as this is said to accelerate the reaction rate. And it seems their approach is correct; the lack of a reaction rate will be faster. But why? Shouldn’t the reaction rate, under the same conditions, depend only on temperature? Under reflux conditions, shouldn’t the temperature of the system be the same regardless of the amount of reflux? So what’s wrong there?
:(Temperature and mixing both have a significant impact; although the overall temperature remains unchanged, the amount of material returning flows back increases, meaning that too much cool material enters. This necessitates an improvement in the heat transfer efficiency of the reactor – the temperature of the material in contact with the reactor walls will definitely be higher than before. Additionally, boiling intensifies, which enhances the mixing of the reactants.)
I learned it. I really didn’t consider that aspect. One of my friends also suggested another possibility. As the reaction proceeds, the sodium alcohol formed creates a \"steric hindrance\" with metallic sodium, making it difficult for metallic sodium to come into contact with the alcohol. Therefore, more energy must be supplied to allow sodium metal to come into contact with tert-butanol in order for a reaction to occur.
{:3_49:} What you’re referring to isn’t steric hindrance; that’s the reaction rate. As the concentrations of alcohol and sodium decrease over time, the reaction rate will slow down no matter what you do. This is similar to cooking slowly over low heat or quickly over high heat – in both cases the temperature remains at 100 degrees. . . . It’s just that the amount of steam generated per unit of time is different, which results in varying drying times
The sodium alcohol feed ratio in my reactor is 2:1. Towards the end of the reaction, the temperature in the reactor exceeds the boiling point of the alcohol I’m using by 20 degrees. Under normal pressure, is there still alcohol in the liquid phase of the material in my reactor? A large amount of alcohol flows back down and then instantly evaporates into gas. The reaction vessel also needs to be heated intensively; if the heating intensity is low, that is, at what you call a \"low heat,\" the reaction stops immediately.
{:3_48:} The liquid phase is definitely a mixture. If the temperature of the material exceeds that of the material with the lower boiling point, then the material with the lower boiling point will evaporate; in that case, what’s the need for a distillation tower? . . .
Right! I took a wrong turn in my thinking: L