Resumen del autor, extraído del trabajo. Raffinate Hydroconversion (RHC) is a new ExxonMobil technology designed to selectively produce Group II basestocks with excellent volatility, viscosity and oxidation properties for next generation automotive fuel-economy lubricants, severe-service industrial oil applications and process oils. The patented process works by efficiently eliminating the highest ring number, highest viscosity species. The process combines under-extraction with a unique three reactor hydroprocessing sequence operating at lower pressures, temperatures and hydrogen consumption than VGO hydrocracking. RHC efficiently converts Group I to high VI Group II basestock quality while maintaining production of both baseoils and waxes. RHC was first commercialized at ExxonMobil's Baytown refinery in November 1999, producing two basestocks having viscosity 6.0 and 4.5 cSt , VI ranging from about 110 to 115 and saturates about 95%. The basestocks have exceptional low volatility and display excellent performance in new automotive categories with prototype additive systems. Current research includes extending the process to heavier feeds and Group III basestocks.