Patent ID: 9567532
Date: 2017-02-14
CPC Classifications: C10G

Claim:
1. A process for producing non-carcinogenic aromatic process oil containing less than 3.0% of a PCA extract according to method IP-346, the process comprising the steps of: (a) refining a petroleum oil fraction with a solvent and extracting residual and distillate extracts from the refined fraction; (b) mixing the residual and distillate extracts with a polar solvent comprising a mixture of dimethyl sulphoxide and N-methylpyrrolidone, wherein a weight ratio of dimethyl sulphoxide to N-methylpyrrolidone is in a range of 1:0.1-0.5; (c) filtering a mixture of the extracts and the polar solvent formed in step (b) to provide (i) a light fraction comprising partially refined petroleum oil extracts and (ii) a heavy fraction comprising an extraction solution; (d) treating the light fraction with the polar solvent to produce a raffinate; and (e) regenerating the polar solvent with use of the heavy fraction.