Abstract: Appling the zeolitic C5/C6 isomerization technology developed by SINOPEC Research Institute of Petroleum Processing (RIPP)， an idle 0.25 Mt/a diesel hydrotreating unit at ShanDong Dongming Petrochemical Grouphas been revamped to a C5/C6 isomerization unit. The feed is C5/C6 light naphtha and raffinate. from CCR unit。Based on principles of feeds’properties， maximum utilization on idle facilities and minimizing investment，the revamp proposed a deheptanizer for raffinate and a “DIP + Once-through” process for the isomerization， producing the C5/C6 isomerate gasoline with RON of 79.7.Unit performance test run indicates that the C5 and C6 isomerization rate of the zeolitic catalyst is 63.2% and 81.1%， respectively. The isomerate achieves an RON of 79.7 and a yield of 98.0%. All the operational results meet the technical control indices.The unit has provided a referential technical solution for the revamp of similar hydrotreating units.

Key words: C5/C6 isomerization, zeolite type isomerization catalyst, clean gasoline