The Pattern Splitter made by Chris Morris is able to help you in this situation. You can read about it in this article: http://www.sqlservercentral.com/articles/String+Manipulation/94365/

And you'll end up with something like this:

SELECT Code, MIN( Item) minvalue, MAX( Item) maxvalue

FROM #temp t

CROSS APPLY dbo.PatternSplitCM(Code, '%[0-9]%')

WHERE Matched = 1

GROUP BY Code