Appropriate does not have a prefix. The Latin origins of the word do make use of Latin prefix however. The word "appropriate" comes from Late Latin appropriatus, past participle of appropriare, from Latin ad- + propriusown.

Words such as Misappropriate use the word appropriate as a root word and add a prefix to it. In the case of misappropriate, the prefix would be mis-.

The related word expropriate drops the a and adds ex-. This is not really an example of a prefix added to the word appropriate, but rather a word coming from the same Latin origins. Expropriate comes from Medieval Latin expropriatus, past participle of expropriare, from Latin ex- + propriusown. As you can see, expropriate comes from a Latin word where a LATIN prefix was added to the same LATIN root word proprius.