To move a lightroom catalog to another drive, create a new root-level folder on the new hard drive.
Close down Lightroom, then copy all the folders from the old drive into the new root-level folder on the new hard drive.
Then in turn right-click on each of the folders on the old and select “Update Folder Location”…
This will pop up a file browser, use this to browse to and select the corresponding folder on the new hard drive and click OK.
This will relink the catalog to the new hard drive.