Is water used in a recommended, non-obligatory purification act impure?
Chapter on what purification is achieved with regarding water
Al-Mughni
Book of Purification
Primary text
There are two narrations concerning water used in recommended, non-obligatory purifications, such as refreshing ablution (Tajdeed), the second and third washings in Wudu' or Ghusl, or washing for Jumu'ah or Eid. One view is that this water is treated like water used to lift an obligatory ritual barrier, as it is a legislated act of purification, similar to washing from Janaabah.
Supporting text
The second view holds that it does not render the water impure because it did not remove an impediment to prayer, resembling water used for cooling down.