Abstract: A process for making propene oxide involves reacting propene with hydrogen peroxide in the presence of methanol, a titanium zeolite epoxidation catalyst, and nitrogen containing compounds present in an amount of from 100 to 3000 mg/kg of hydrogen peroxide. Non-reacted propene is separated from the reaction mixture; the propene depleted reaction mixture is continuously distilled in a distillation column providing an overhead product stream containing propene oxide and methanol and a bottoms product stream; and propene oxide is separated from the overhead product stream. An acid is added to the propane depleted reaction mixture and/or to the distillation column at the same level or above the feed point for the propene depleted reaction mixture and/or contacted to the feed to the distillation column to provide an apparent pH in the bottoms product stream of from 3 to 4.5, which reduces the nitrogen content of the separated propene oxide.

Abstract: A process for making propene oxide involves reacting propene with hydrogen peroxide in the presence of methanol, a titanium zeolite epoxidation catalyst, and nitrogen containing compounds present in an amount of from 100 to 3000 mg/kg of hydrogen peroxide. Non-reacted propene is separated from the reaction mixture; the propene depleted reaction mixture Is continuously distilled in a distillation column providing an overhead product stream containing propene oxide and methanol and a bottoms product stream; and propene oxide is separated from the overhead product stream. An acid is added to the propane depleted reaction mixture and/or to the distillation column at the same level or above the feed point for the propene depleted reaction mixture and/or contacted to the feed to the distillation column to provide an apparent pH in the bottoms product stream of from 3 to 4.5, which reduces the nitrogen content of the separated propene oxide.

Abstract: The present invention pertains to a process for preparing 3-hydroxy-3-methylbutyrate (HMB) or a salt thereof, the method comprising (a) reacting isobutylene oxide with cyanide in order to obtain 3-hydroxy-3-methylbutyronitrile, and (b) hydrolyzing the 3-hydroxy-3-methylbutyronitrile obtained in step (a) in order to obtain HMB, wherein hydrolysis step (b) is performed using either at least one nitrilase enzyme or, alternatively, using a combination of enzymes, said combination comprising at least one nitrile hydratase and at least one amidase.