Sulfur production process

摘要

A process is provided for the removal of trace amount of aromatic hydrocarbons from a waste feed gas stream comprising sulfur compounds and the aromatic hydrocarbons. An adsorption process employing an adsorbent such as a high silica zeolite adsorbent having a framework silica to alumina ratio greater than about 15 and having a pore size greater than about 6.2 Angstroms is used to remove from the feed gas mixture aromatic hydrocarbon contaminants and permit the recovery of a high purity sulfur product from the treated effluent stream. The adsorption zone comprises at least 2 adsorption beds wherein one of the first adsorption beds is operating in an adsorption mode and the other is being regenerated at a desorption pressure higher than the adsorption pressure. The regeneration is performed in a closed system or partially closed system, and prior to returning a regenerated adsorption zone to adsorption conditions the waste feed gas stream is used to cool and purge the regenerated zone. Purge effluent from the regeneration zone is passed to a bed undergoing adsorption in a lead/trim configuration to prevent a slug of aromatic hydrocarbons from entering the adsorption effluent. The use of the present invention removes aromatic hydrocarbon contaminants which are responsible for the degeneration of the performance of the downstream sulfur recovery zone.