Removal of acidic gases from hydrocarbon streams

Claim 1

In a cyclic process for substantially reducing the carbon dioxide and/or hydrogen sulfide content present as acidic gases in a gas obtained from the cracking of a hydrocarbon selected from the group consisting of gas oil, naphtha and ethane, and said gas further containing undesirable organic impurities therein, with simultaneous regeneration of reagent materials which comprises: a. passing the cracked gas containing the acidic gases through an aqueous sodium hydroxide solution and obtaining an effluent containing the undesirable organic impurities and said acidic gases in converted form; b. reacting said effluent liquid with aqueous sulfuric acid or an aqueous mixture containing sulfuric acid and sodium sulfate in an amount sufficient to substantially liberate the converted acidic gases consisting essentially of hydrogen sulfide and/or carbon dioxide that may be present therein; c. subjecting said treated effluent liquid to a stripping operation to remove any liberated gases therefrom and thereby leaving an aqueous sodium sulfate containing solution; and d. subjecting said resulting aqueous sodium sulfate containing solution to an electrolytic process treatment whereby aqueous sulfuric acid or an aqueous mixture of sulfuric acid and sodium sulfate is collected at the anode and is recycled for utilization in the aforesaid reaction step and aqueous sodium hydroxide which forms at the cathode is collected and recycled for use in the sodium hydroxide treatment step, the improvement which comprises treating the effluent from the alkali metal hydroxide treatment of step (a) to remove substantially all organic impurities therefrom.