Meme question d'Adrian

Question

Why: "afin de pouvoir les utiliser comme un engrais naturel"

when, "afin l'utiliser comme un engrais naturel"

would seem to be a more elegant answer, and be a more literal translation? Adding pouvoir seems to complicate the issue.

Accepted Answer

The phrase is afin de + infinitive

Answer

Paul, Chris is correct. “Afin” does not stand alone - it is part of the locutions ‘afin de (infinitive)’ or ‘afin que (subjunctive)’. An object pronoun can come before the infinitive with afin de, and a subject pronoun can come before the subjunctive with ‘afin que’.
With respect to your original question, no this was not a direct word for word translation, but it is very common in French to use ‘pour pouvoir ….’ (or in formal speech or writing, afin de pouvoir . . . ), when in English we could say “in order to be able to”, but are more likely to just say ‘in order to’ or ‘(so as) to be able to’. Leaving ‘pouvoir’ out is not wrong or incomprehensible, but it is very natural for French native speakers to include it.
To me, the inclusion of ‘pouvoir’ generally seems to indicate that what is being done (now) is not going to immediately or directly lead to the final outcome mentioned, but is part of the process leading there. This is not hard and fast though. 
This is an exercise at B2 level - it is to be expected that translations will not always be literal or word for word, as at this level a good understanding of colloquial, current  French usage is expected. Both languages, however, should sound as natural as possible to their native speakers. 
 
 
 https://www.dictionnaire-academie.fr/article/A9A0798 https://www.larousse.fr/dictionnaires/francais/afin_que/1562 https://www.wordreference.com/fren/afin

Answer

Chris, my "Barron's French Verbs" does not agree with you that afin is followed by de + infinative!