Getting rid of 32 bit packages in RedHat
From MyWiki
If You want to clean your RedHat (or a derivative) off 32 bit packages, have a look here
In short:
yum remove \*.i\?86
To keep 32-bit packages from being installed in future updates, edit your /etc/yum.conf and add the line:
exclude = *.i?86
Be aware that 32-bit applications, including some browser plugins that may only be available in 32-bit versions, will no longer work after this procedure.