72 research outputs found
Use of Ionic Liquid in Fabrication, Characterization, and Processing of Anodic Porous Alumina
Two different ionic liquids have been tested in the electrochemical fabrication of anodic porous alumina in an aqueous solution of oxalic acid. It was found that during galvanostatic anodization of the aluminum at a current density of 200 mA/cm2, addition of 0.5% relative volume concentration of 1-butyl-3-methylimidazolium tetrafluoborate resulted in a three-fold increase of the growth rate, as compared to the bare acidic solution with the same acid concentration. This ionic liquid was also used successfully for an assessment of the wettability of the outer surface of the alumina, by means of liquid contact angle measurements. The results have been discussed and interpreted with the aid of atomic force microscopy. The observed wetting property allowed to use the ionic liquid for protection of the pores during a test removal of the oxide barrier layer
ChemInform Abstract: Organo-Transition-Metal-Modified Sugars. Part 11. Stereospecific exo-Selective Diels-Alder Reactions with Carbohydrate-Functionalized α-exo-Methylene-2-oxacyclopentylidene Chromium Complexes.
ChemInform Abstract: Reactions of Complex Ligands. Part 87. Novel Approach to 6-Chromanols via Photochemical Benzannulation of α-exo-Benzylidene-2-oxacyclohexylidene Chromium Complexes.
ChemInform Abstract: Reactions of Complex Ligands. Part 83. Photochemical Activation of (α-exo-Alkylidene-2-oxacyclopentylidene)chromium Complexes for Benzannulation.
Biphasic Hydrosilylation in Ionic Liquids: A Process Set for Industrial Implementation
The biphasic hydrosilylation of 1-hexadecene with siloxane B9800 in a range of ionic liqs. is reported. Of the ionic liqs. tested, [C4py][BF4] and [C4-3-pic][BF4] offer the optimum compromise between activity and catalyst retention. Several platinum precatalysts were screened, of which K2PtCl4 and Pt(PPh3)4 were found to give the best performance; the former provides the highest activity, while the latter offers higher stability and recyclability, and depending on the conditions, both can afford either homogeneous or sol. nanoparticle catalysts as the active species. A no. of reaction parameters were varied, and the effects of oxygen, water, and chloride impurities on the reaction were studied. In addn., since nanoparticle catalysts were obsd., various strategies to stabilize nanoparticles were screened, but none of them resulted in a superior catalytic system
The effect of the morpholinium ionic liquid anion on the catalytic activity of Rh (or Pt) complexâionic liquid systems in hydrosilylation processes
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