摘要 |
<p>Process for treating filtration panels obtained by the filtration of oils containing sulfonates of earth-alkaline metals, whereby the aforesaid filtration being carried out in the presence of filter aids essentially consisting of siliceous material, which comprises the following steps: (a) dilution of the filtration panel with a C4-C8 aliphatic hydrocarbon, preferably hexane, and addition of another filter aid, thus obtaining a suspension of the panel and of the filter aid in the aliphatic hydrocarbon; (b) filtration of the suspension of step (a), thus obtaining a solid essentially consisting of filter aid with a minimum content of sulfonate and a turbid C4-C8 hydrocarbon solution (i); (c) centrifugation of the turbid hydrocarbon solution (i), thus obtaining a solid and a purified hydrocarbon solution (ii); (d) treatment of the purified hydrocarbon solution (ii) with means suitable for eliminating the C4-C8 hydrocarbons, thus recovering the sulfonate of earth-alkaline metal.</p> |