.[.In a hydrogenation operation employing an ebullated catalytic bed, recycle is recovered from the hydrogenated product with at least 25%, by volume, of the recycle boiling above 950.degree. F. The recycle is cooled to a temperature of from 350.degree. to 600.degree. F. to separate coke precursors,...http://www.google.com.au/patents/USRE32265?utm_source=gb-gplus-sharePatent USRE32265 - Hydrogenation of high boiling hydrocarbons
