Process steps:
1. Sulfonation, using 150-500SN base oil from petroleum refinery as raw material, using SO3 gas to sulfonate;
2. Extraction Separate, use alkyl alcohol as the extraction agent, according to the weight ratio of acidic oil: alkyl alcohol = 0.5 ~ 10;
3. Second sulfonation, after extracting the oil and dehydration, perform the second Sulfenation;
IV. Neutralization and concentration. Dissolve the lower liquid after the first sulfonation and the second sulfonation extracted by the extractant with a solid inorganic base in an alkyl alcohol. After completion, neutralization, distillation and concentration after neutralization, and a petroleum sulfonate product is obtained after the alkyl alcohol is evaporated. Increase oil recovery by 19-24%.
(This method has been patented, patent number 01110282)