(159f) CS2 Removal from Polymer Grade Naphtha/Cracked Gas

Ethylene producers have linked carbon disulfide (CS₂) in petrochemical grade naphtha/cracked Gas to corrosion in locations downstream of the cracker and to deterioration of Pygas hydrogenation catalyst activity. CS₂ can poison the selective hydrogenation catalyst that is generally used to remove acetylenes and dienes in olefin plants. CS₂ also contaminates C4 and C5 olefins and diolefins production in polymer plants and can be corrosive when it undergoes transformation to H₂S. This has led some producers to implement very low specifications (ppm levels) of CS₂ in petrochemical grade naphtha. Other producers have also indicated CS₂ as a primary contaminant particularly in some shale derived feedstocks. Thus CS₂ contamination can effectively limit feedstock flexibility and associated costs.

Chemical neutralization of CS₂ represents an economically attractive solution. To help meet this growing need, Dorf Ketal has developed a new additive for CS₂ removal from Petrochemical grade naphtha/NGL &/ or Cracked Gas. The new additive can remove CS₂ efficiently thereby upgrading PGN/NGL feeds. This paper will demonstrate the results of extensive lab testing with a variety of commercial feeds conducted to prove economic viability of an additive solution.