You can implement your own Camel Expression and use that with the splitter. Then you can read the CXF data in chunks, such as X rows.
This should be implemented as an Iterator, which the Camel Splitter, then will use.
You would also need to enable streaming mode on the Splitter.
For example see the source code, such as the token pair iterator
The API has changed slightly in Camel 2.9, so you would need to adjust accordingly in older Camel releases.