Turns out that I can use the Split function after all, as the space width wasn't an issue as I thought it would be.

Sorry if I wasted anyones time
[vba]
Public Sub Process_PN_String()
Dim strArr() As String
Dim MyStr As String
Dim LastRow As Long
Dim rng As Range
Dim cell As Range
Application.ScreenUpdating = False

With ActiveSheet

LastRow = .Cells(.Rows.Count, "A").End(xlUp).Row

Set rng = .Range(.Cells(1, 1), .Cells(LastRow, 1))

For Each cell In rng

MyStr = Trim(cell.Value)
strArr = Split(MyStr, Space(1))
On Error Resume Next ' to avoid error if row is empty

cell.Offset(0, 1).Value = Trim(strArr(0))

Next cell
End With

Application.ScreenUpdating = True
End Sub
[/vba]