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An ionic-liquid-like copolymer was used to stabilize the platinum nanoclusters in ionic liquids. Catalytic performance was tested by the selective hydrogenation of o-chloronitrobenzene. Platinum catalysts Pt-I (5.1 nm) and Pt-II (1.7 nm) both exhibited excellent activity and selectivity for the reaction and were recycled with the activity and selectivity preserved. An unprecedented total turnover number (>25,900) was obtained on the Pt-II catalyst. Infrared spectroscopy, transmission electron microscopy, X-ray diffraction characterizations, and density functional theory calculations were used to study the catalysts.

Rhodium nanoparticles stabilized by the ionic-liq.-like copolymer N-Vinyl-2-pyrrolidone-1-vinyl-3-butylimidazolium chloride-1-vinyl-3-ethylimidazolium bromide copolymer were used to catalyze the hydrogenation of benzene and other arenes in ILs. The nanoparticle catalysts can endure forcing conditions (75 °C, 40 bar H2), resulting in high reaction rates and high conversions compared with other nanoparticles that operate in ILs. The hydrogenation of benzene attained record total turnovers of 20,000, and the products were easily sepd. without being contaminated by the catalysts. Other substrates, including alkyl-substituted arenes, phenol, 4-n-propylphenol, 4-methoxylphenol, and phenyl-methanol, were studied and in most cases were found to afford partially hydrogenated products in addn. to cyclohexanes. In-depth investigations on reaction optimization, including characterization of copolymers, TEM, and an IR spectroscopic study of nanocatalysts, were carried out.

Platinum, palladium and rhodium nanoparticles stabilized by poly(N-vinyl-2-pyrrolidone) (PVP) can be synthesized by ethanolic reduction of the corresponding metal halide salts and when immobilized in an ionic liquid, 1-n-butyl-3-methylimidazolium hexafluorophosphate ([BMI][PF6]), are very effective olefin hydrogenation catalysts which are capable of being recycled by a simple decantation procedure without loss of activity.

The objective of this study is to optimize the conditions for the hydrolysis of corn cob in formic acid. The effects of the formic acid concentration, reaction temperature and reaction time were investigated. The results indicated that 96.3% of xylose yield could be obtained at 100 °C for 120 min in 60% (w/w) formic acid under the microwave-assisted conditions. However, under traditional oil-bath heating condition, the corresponding xylose yield was only 75.1%. On the other hand, under the microwave-assisted conditions when the corn cob was treated in 60% (w/w) formic acid at 100°C for 150 min, 71.7% of delignification yield could reached while only 31.9% of lignin was removed in oil-bath heating condition. It can be inferred that the combination of formic acid and microwave was an effective method for corn cob pretreatment.