Have you tried filtering the data directly in the worksheet instead (Autofilter or Advanced filter)? Filtering out duplicates from 10,000 records takes seconds, not minutes. For example, this will remove all duplicate values from the data in column A.

Sub main()
Dim ws As Worksheet
Dim rng As Range
Dim rngToDelete As Range
Set ws = Worksheets("Sheet1")
'Advanced Filter requires a header row - let's add a temporary one
ws.Rows(1).Insert
ws.Cells(1, 1).Value = "temp header"
Set rng = ws.Range("A1:A10000")
rng.AdvancedFilter xlFilterInPlace, unique:=True
Set rngToDelete = rng.SpecialCells(xlCellTypeVisible)
ws.ShowAllData
rngToDelete.EntireRow.Hidden = True
rng.SpecialCells(xlCellTypeVisible).EntireRow.Delete
rngToDelete.EntireRow.Hidden = False
'remove the temporary row
ws.Rows(1).Delete
End Sub