Split () Then Replace () Text Box Input

I have a form with an text box called keywords. I want to get the text typed in by the user from this box (which will pobably be built up of several words).

I have declared arrsplitkeywords to assign these words to. But first i have split the input from the text box where there is a space. See the line of code below:

arrsplitkeywords = Split(Request.Form("Keywords"),",")

I now need to replace this so that the words are split up to be split like "','" I have the following line of code to do this:

Replace(arrsplitkeywords,",", "','")

This doesn't appear to work, and on the replace line i get the following error:

Error Type:
Microsoft VBScript compilation (0x800A0401)
Expected end of statement

Any help please as to why this isn't working?