Cobalt-molybdenum (CoMo) catalysts are integral components of tail gas units (TGUs), playing a vital role in reducing harmful sulphur dioxide (SO2 ) emissions arising from Claus sulphur recovery units. Effective activation of these catalysts is essential for their optimal performance. The consequence of sulphiding at low temperatures and atmospheric pressure in low temperature TGUs is to compromise effectiveness of catalyst activation. In the final part of this two-part article, Michael Huffmaster , Consultant, presents case study results using a discrete reactor model incorporating heat, mass transfer, and activation reaction kinetics to assess the impacts of these variables on in-bed temperature profile and activation effectiveness. Tailoring gas rate, composition, and temperature progression can achieve in-bed exotherms which improve CoMo catalyst activation effectiveness for low temperature tail gas units.
