In ThisWorkbook code module, add
Const Timeout As Long = 10 ' 10 minutes
Private Sub Workbook_Open()
dTime = Time
On Error Resume Next
Application.OnTime dTime + TimeSerial(0, Timeout, 0), "CloseMe"
On Error GoTo 0
End Sub
Private Sub Workbook_SheetSelectionChange(ByVal Sh As Object, ByVal Target As Range)
On Error Resume Next
Application.OnTime dTime + TimeSerial(0, Timeout, 0), "CloseMe", , False
dTime = Time
Application.OnTime dTime + TimeSerial(0, Timeout, 0), "CloseMe"
On Error GoTo 0
End Sub
and in a standard code module add this code
Public dTime As Double
Sub CloseMe()
ThisWorkbook.Close SaveChanges:=True
End Sub