Musannaf Ibn Abi Shaybah

Hazrat Ibn Umar (may Allah be pleased with them both) narrates that do not purchase the purification of your wealth.

Hazrat Abu Zubair says that I heard Hazrat Jabir saying that when the collector of Zakat comes, then give him your Zakat. And do not buy from him. People say that buy from him. I say that indeed, it now belongs to Allah.

A person asked Hazrat Imam Zuhri whether a man can buy his paid Zakat. He replied: He cannot buy it from the one who received the Zakat, until that person leaves. And after he leaves, he should not buy it until it gets mixed with a large number of goats.

It is narrated from Hazrat Ata that indeed the early companions disliked purchasing items given as Zakat. Hazrat Ata says that if, after you, someone else takes possession of the Zakat, then there is no harm.