Ingrid Kristine Meier

Hydration of acetylenic compounds without using mercury

Copper(II), palladium(II) and silver(I), in conjunction with non-coordinating anion environments, have been found to catalyze the hydration of a variety of functionalized and nonfunctionalized alkynes. Suitable anions include trifluoromethane sulfonate, tetrafluoroborate, and sulfonate groups on perfluorinated ion-exchange resins. These catalyst systems are the first reported catalysts that are active for the hydration of acetylenic alcohols in high selectivity and do not contain mercury. The problems of dehydration and byproduct formation, observed when other catalysts are used with these alcohols, are minimized.

SELECTIVITY ENHANCEMENT VIA PHOTOOXIDATIVE SURFACE MODIFICATION OF POLYIMIDE AIR SEPARATION MEMBRANES

Abstract The scope and limitations of photooxidative surface modification of polyimide films were investigated as means of improving the selectives of air separation membranes without drastically reducing their permeabilities. Membranes of polyimides that contained the phthalimide chromophore and abstractable hydrogens showed significantly higher oxygen/nitrogen selectivities after being irradiated with ≈ 200–300 nm light in the presence of oxygen for 0.5·-30 min. Not only were benzylic hydrogens found to be abstractable, but also certain t -butyl hydrogens could be abstractable uder these conditions. A mechanism for the phtochemical reaction that is based on the photochemistry of structurally similar monomeric phthalimides is proposed to explain the observed selectivity enhancement.