Showing papers on "Nickel boride published in 1971"

A process for the preparation of 3- (3beta, 17beta-dihydroxyandrost-5-en17alpha-yl) propionic acid-gamma-lactone

Abstract: 1365437 Nickel borides G D SEARLE & CO 1 Aug 1972 [6 Aug 1971] 35793/72 Heading C1A [Also in Division C2] A nickel boride catalyst is prepared in Examples 5B and 5C by addition of sodium borohydride in water to a mixture of nickel chloride hexahydrate and small amount of chromium chloride hexahydrate in methanol and water.

Hydrogenation of Triolein with Various Catalysts

Abstract: Triolein was hydrogenated under various operating conditions. Five types of catalysts were employed. Platinum and palladium catalysts were used at 50°C and each of three types of nickel catalyst was used at 160°, 180°, 200° and 220°C. The hydrogenated products were subjected to lipase hydrolysis (lipolysis) to remove a portion of the acyl groups on the α, α'-positions. The hydrogenated products and fatty acids liberated by lipolysis were analyzed for fatty acid compositions and for content of the trans isomers. In case of nickel boride catalyst, the results showed that the oleoyl groups on α, α'-positions of triolein molecule are hydrogenated slightly faster than that on β-position. The other catalysts have not shown the selectivity of hydrogenation toward the position of acyl groups. There was no relation to be discussed between the position of acyl groups and the formation of trans isomers during hydrogenation with each nickel catalyst. Upon comparison at the same iodine value, trans isomer content in hydrogenated products was the most in case of nickel boride catalyst.

Vergleichende Untersuchungen zur katalytischen Aktivität von Nickel und kristallinen Nickelboriden sowie RANEY‐Nickel und borhaltigem RANEY‐Nickel: Hydrierungs‐ und Dehydrierungsreaktionen, elektrochemische Methanoloxydation

Abstract: Die katalytische Aktivierung des Zerfalls der gasformigen Ameisensaure durch Nickelpulver und kristalline Nickelboride wird verglichen. Die Nickelboride erreichen erst nach Behandlung mit NH3-Losung grosenordnungsmasig die Aktivitat des Nickelpulvers. Ni3B zeigt die gunstigsten Eigenschaften. Bei der anodischen Methanoloxydation in alkalischer Losung bei 80°C sind die kristallinen Nickelboride inaktiv. – Borhaltige Nickelkatalysatoren, die nach dem RANEY-Verfahren aus Nickelborid und Aluminium gewonnen werden, hydrieren in Losung die CCBindung der Crotonsaure gleich schnell wie RANEY-Nickel; die COBindung des Acetons wird an ihnen schneller hydriert. In alkalischer Losung kann an RANEY-Nickel enthaltenden Elektroden Methanol bei 80°C anodisch mit beachtlicher Geschwindigkeit oxydiert werden. Borhaltiges RANEY-Nickel ist noch wirksamer. The catalytic activation of the decomposition of gaseous formic acid with nickel powder and crystalline nickel borides is compared. Only after treatment with NH3-solution the activity of the nickel borides has the same order as that of nickel powder. Ni3B is the best of the catalysts used. The crystalline nickel borides cannot catalyze the anodic oxydation of methanol in alcaline solution at 80°C. — Nickel catalysts containing Boron can be prepared by the RANEY method from nickel boride and aluminum. These catalysts have the same activity as normal RANEY nickel with respect to the hydrogenation of the CCbond in crotonic acid; they are more active with respect to the CObond of acetone. Methanol can be oxydised fastly in alcaline solution at 80°C on electrodes containing RANEY nickel. RANEY nickel containing boron is still better.