[lukas.stib]

Hello chemists,

I want to make ethyl esters of malic acid and citric acid using the classic Fischer´s esterification of acid+ethanol+sulfuric acid, and I want to ask whether I should dry the acids or use them without drying? Malic and citric acid are commonly purchased food grade acids.

Thank you, Lukáš S.

[Orcio_87]

Did you read about their physical properties ? Malic and cytric acid are stable to about 130 C and decomposes above. Drying (at about 105 C) will last about 1 hour, but can improve yield of reaction by few percents.

[lukas.stib]

OK, thank you.

[Babcock_Hall]

One can dry some compounds in a vacuum in the presence of P₂O₅.

[wildfyr]

Unless they are totally soaking wet, I think you can effectively esterify these by running the reaction in pure ethanol. Its an old trick.

Drying with phosphorous pentoxide is by far the most effective and mild method if you need any reagent to be very dry.