Adsorption-based system and method for claus tail gas treatment

A tail gas treatment system, the system comprising:

• a hydrogen sulfide adsorption unit comprising at least one hydrogen sulfide adsorption vessel, wherein each hydrogen sulfide adsorption vessel comprises:
• one or more inlets configured to receive a gas stream that comprises hydrogen sulfide and carbon dioxide;
• an ion-exchanged zeolite positioned in the hydrogen sulfide adsorption vessel, wherein the ion-exchanged zeolite is configured to adsorb at least a portion of the hydrogen sulfide and allow the carbon dioxide to pass through the ion-exchanged zeolite;
• one or more outlets configured to dispense the carbon dioxide from the hydrogen sulfide adsorption vessel during an adsorption cycle, wherein the one or more outlets are configured to dispense the hydrogen sulfide from the hydrogen sulfide adsorption vessel during a regeneration cycle;
• a first valve positioned downstream of the one or more outlets, wherein during the adsorption cycle the first valve is moveable to an open position to allow the carbon dioxide to pass through the first valve and exit the hydrogen sulfide unit via a first output stream, and during the regeneration cycle the first valve is movable to a closed position to restrict hydrogen sulfide from passing through the first valve to the first output stream;
• and
• a second valve positioned downstream of the one or more outlets, wherein during the adsorption cycle the second valve is movable to a closed position to restrict the carbon dioxide from passing through the second valve to a second output stream of the hydrogen sulfide adsorption unit, and during the regeneration cycle the second valve is movable to an open position to allow the hydrogen sulfide to pass through the second valve and exit the hydrogen sulfide unit via the second output stream.