GB787745A - Process for removing weakly acidic substances, especially mercaptans, from hydrocarbon fluids - Google Patents

Abstract

Weakly acidic substances, particularly mercaptans, are extracted from hydrocarbon fluids, using aqueous alkali metal hydroxide solutions (M.O.H.) in combination with the particular concentration of solutizer which when contacted with M.O.H. forms an aqueous alkali metal hydroxide phase and an alkali metal hydroxide and solutizer phase (M.O.R.), the mercaptan being concentrated in the solutizer phase and subsequently the acidic substance is stripped therefrom. The procedure of extraction may be performed as follows: (a) The weakly acidic substances are stripped with M.O.H. solution, the acids are concentrated in the M.O.R. phase by mixing the phases and then the acids are stripped from the M.O.R. phase and the solutions recirculated. (b) In removing acids such as heavy mercaptans the solutizer phase is the extracting phase and this is fortified after stripping with the M.O.H. phase. (c) The both phases may be used together, or separately, successively or simultaneously. The method of the invention is also applicable to the regeneration of fouled aqueous alkali metal hydroxide solutions. The prior art use of solutizer solutions is discussed in connection with U.S.A. Specifications 2,059,075, 2,066,925, 2,149,379, 2,149,380, 2,151,722, 2,151,723, 2,152,166, 2,156,577, 2,164,851, 2,168,078, 2,202,039, 2,223,789 and 2,229,995.