Virtual Service Catalog cannot be run as a service at this time.
From folder /opt/CA/vscatalog/IdentityAccessManager/bin execute:
./IdentityAccessManager > ~/iam.log 2>&1 &
From folder /opt/CA/vscatalog/bin execute:
./vscatalog > ~/vscat.log 2>&1 &
The output, iam.log and vscat.log (just names given, they can be named anything), will get written to the home folder of the user that is logged in and starting the components.
You can now start these components in background and log off the machine and they will still be running.