It's not clear from your post whether AD01 may be in a named range, or if you want just the column's address. For the column, all you need is:
ActiveCell.EntireColumn.Address
If you're referring to a range name that might apply to a cell, that's a bit more complicated, since a Range object can have more than one name and there’s no Names collection for the Range object. The following macro shows how you can use Name with a Range object to return the names assigned to the range:
Code:
Sub FindRangeName()
Dim oName As Name, oRng As Range, oCell As Range
On Error Resume Next
For Each oName In ActiveWorkbook.Names
Set oRng = Range(oName.Name)
If Err = 0 Then
If Not Intersect(ActiveCell, oRng) Is Nothing Then
If oRng.Address = ActiveCell.EntireColumn.Address Then _
MsgBox "The Name " & oName.Name & " spans the selected column."
End If
Err = 0
End If
Next
End Sub
As coded, the name must span the entire column; no more and no less.