Use of Solvent to Decrease Caustic Scrubber Fouling

A method of reducing the formation of fouling deposits occurring in a caustic scrubber used to remove acid gases comprising:

• a) providing a caustic scrubber fed with an alkaline aqueous solution comprising NaOH, KOH, LiOH, or combinations thereof;
• b) providing an olefin-containing hydrocarbon stream contaminated with oxygenated compounds and acid gases, wherein the oxygenated compounds are capable of making polymeric fouling deposits in the presence of the alkaline aqueous solution;
• c) sending the olefin-containing hydrocarbon stream to the caustic scrubber to recover an olefin-containing hydrocarbon stream essentially free of acid gases;
• d) wherein an efficient amount of a solvent capable reducing the formation of fouling deposits is introduced in the caustic scrubber, in the alkaline aqueous solution fed to the caustic scrubber, or combinations thereof;
• e) wherein a liquid outlet of the caustic scrubber is sent to means to separate the solvent from the alkaline aqueous solution;
• and
• f) optionally, wherein an additive is introduced in the caustic scrubber, the alkaline aqueous solution, or combinations thereof, wherein the additive is capable of reducing the conversion of the oxygenated compounds to polymeric fouling deposits in the presence of the alkaline aqueous solution.

A method of reducing the formation of fouling deposits occurring in a caustic scrubber used to remove acid gases comprising:

• a) providing a caustic scrubber fed with an alkaline aqueous solution comprising NaOH, KOH, LiOH, or combinations thereof;
• b) providing an olefin-containing hydrocarbon stream contaminated with oxygenated compounds and acid gases, wherein the oxygenated compounds are capable of making polymeric fouling deposits in the presence of the alkaline aqueous solution;
• c) sending the olefin-containing hydrocarbon stream to the caustic scrubber to recover an olefin-containing hydrocarbon stream essentially free of acid gases;
• d) wherein an efficient amount of a solvent capable reducing the formation of fouling deposits is introduced in the caustic scrubber, in the alkaline aqueous solution fed to the caustic scrubber, or combinations thereof, wherein a weight ratio of the solvent to the flow of the alkaline aqueous solution is up to 0.1, and wherein the solvent is essentially immiscible with the alkaline aqueous solution;
• e) wherein a liquid outlet of the caustic scrubber is sent to means to separate the solvent from the alkaline aqueous solution;
• and
• f) optionally, wherein an additive is introduced in the caustic scrubber, the alkaline aqueous solution, or combinations thereof, wherein the additive is capable of reducing the conversion of the oxygenated compounds to polymeric fouling deposits in the presence of the alkaline aqueous solution.