Treatment method for spent caustic soda
AssigneeSK Energy Co., Ltd.
InventorsBang Un Song, Sung Ho Lee, Young Seek Yoon, Seung Hoon Oh
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Abstract
An embodiment of the present invention relates to a method for treating spent caustic soda generated from an oil refinery process, a petrochemical process, etc. through a process in which a series of treatment steps are integrated, wherein the method can constitute a process under mild conditions excluding high temperature and/or high pressure conditions and can be advantageous to a post treatment process since the amount of by-products is small.
Claims26
A method of treating spent caustic soda, comprising the steps of:
- a) providing spent caustic soda generated from at least one of an oil refining process and a petrochemical process;
- b) adding an acid to the spent caustic soda to neutralize the spent caustic soda to a pH of 1 to 9 to separate the spent caustic soda into an upper-layer fraction and a lower-layer fraction by layer separation and then recovering the upper-layer fraction as a by-product;
- and
- c) oxidation-treating the lower-layer fraction in the presence of a trivalent iron-containing catalyst by the addition of an oxidant.
A method of treating spent caustic soda, comprising the steps of:
- a) providing spent caustic soda containing mercaptan in an amount less than the amount selected from 150 to 200 mg/L, the mercaptan being introduced during a procedure of treating a product obtained from at least one of an oil refining process and a petrochemical process with caustic soda;
- b) adding an acid to the spent caustic soda to neutralize the spent caustic soda to a pH of 1 to 5 to separate the spent caustic soda into an upper-layer fraction and a lower-layer fraction by layer separation and then recovering the upper-layer fraction as a by-product;
- and
- c) oxidation-treating the lower-layer fraction in the presence of a trivalent iron-containing catalyst by the addition of an oxidant.
A method of treating spent caustic soda, comprising the steps of:
- a) providing spent caustic soda containing mercaptan in an amount more than the amount selected from 150 to 200 mg/L, the mercaptan being introduced during a procedure of treating a product obtained from at least one of an oil refining process and a petrochemical process with caustic soda;
- b) adding an acid to the spent caustic soda to neutralize the spent caustic soda to a pH of 5 to 9 to separate the spent caustic soda into an upper-layer fraction and a lower-layer fraction by layer separation and then recovering the upper-layer fraction as a by-product;
- and
- c) oxidation-treating the lower-layer fraction in the presence of a trivalent iron-containing catalyst by the addition of an oxidant.
Dependencies are inferred from the claim text.