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Is straight run heavy naphtha treated in a merox unit fit to be used as feed in fixed bed bi metallic i.e. platinum rhenium based catalyst, platformer unit for octane improvement?
 
Answers
20/07/2009 A: Virendra Kapoor, Petroleum Refining Consultants, vkkapoor9@yahoo.com
Platformer catalysts require that organic sulfur, nitrogen should be less than 0.5 or 1.0 ppm in the feed. likewise there is limit for other poisons too. Merox treatment of heavy naphtha converts acid sulfur into disulfides. Merox treated naphtha fed to Platformer will deactivate catalyst. So it can not be fed till hydrotreatrd to be free of poisons. Hydrotreatment converts sulfur to hydrogen sulfide and nitrogen to ammonia which are removed in stripper and CRU charge naphtha has sulfur and nitrogen less than 0.5 ppm.
20/07/2009 A: Lindsay McRae, Pall Corporation, Lindsay_McRae@pall.com
Hydrotreating reformer feed is more common but if feed is sweet enough and doesn't contain metals, It might be possible. However, if Heavy Naphtha from Merox unit is fed to reformer, trace amounts of caustic and water carried over from Merox unit may deactive Pt / Rh catalyst in reformer which is very sensitive indeed to both sodium and also to water. So it might be possible. However a high efficiency PhaseSep Liquid Liquid coalescer would be recommended to get sodium level to <0.5 ppm and free water to <15 ppmw to protect reformer catalyst. Pall Corporation PhaseSep coalescers are often used downstream of Merox units to remove sodium / water from FCC gasolene, LPG, or Kero merox units.
19/07/2009 A: keith bowers, B and B Consulting, kebowers47@gmail.com
The bi-metallic reforming catalyst is very sensitive to poisoning by sulfur. TOTAL SULFUR is the key measurement criteria for feedstock quality in this regard. In almost all cases, hydro-treating is required to remove all the sulfur and other catalyst poisons in the feedstock. Only complete analysis of the potential feedstock will definitively answer your question. Likelihood of 'merox treated' feedstock meeting requirements is vanishingly low.