Abstract: The formation of SO.sub.3 mists is prevented by covering the oleum with a natural silicate excluding sand.

Abstract: A process for preparing the potassium peroxomonosulfate triple salt 2 KHSO.sub.5 .multidot.KHSO.sub.4 .multidot.K.sub.2 SO.sub.4 by partial neutralization of sulfuric acid-Caro's acid fed to a working solution containing KHSO.sub.5, KHSO.sub.4 and K.sub.2 SO.sub.4 with caustic potash solution and evaporation of water. The cold crystallization procedure (15.degree. C. or below) hitherto required is avoided and a high active oxygen yield is produced by using sulfuric acid-Caro's acid with 50 to 70 wt. % of H.sub.2 SO.sub.5 and 15 to 30 wt. % of H.sub.2 SO.sub.4 and a working solution with a concentration of 28 to 38 wt. % of KHSO.sub.5, 18 to 28 wt. % of KHSO.sub.4 and greater than 0 to 3 wt. % of K.sub.2 SO.sub.4 and supplying additional sulfuric acid, wherein the molar ratio of H.sub.2 SO.sub.5 to added H.sub.2 SO.sub.4 to KOH is 3 to 1:3 to 5:8.

Abstract: The present invention provides a process for the preparation of substantially pure silibinin from the fruit of Silybum marianum, as well as pharmaceutical compositions containing it for the treatment of diseases of the liver.