Some dicationic ionic liquids, N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid ethylenediammonium hydrogen sulfate, N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid 1,3-propanediammonium hydrogen sulfate, N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid 1,6-hexanediammonium hydrogen sulfate, were prepared. These ionic liquids could be used as efficient and recyclable catalysts for the synthesis of biodiesel from free long-chain fatty acids or their mixtures with low-molecular-weight alcohols as substrates. the reaction was accomplished in a monophase at 70 °C for 6 h, while the products was separated from the catalyst system by liquid/liquid biphase separation at room temperature with good yields of 93−96%. The post processing was simple, and after removal of water, the catalysts could be reused at least six times and the decrease in the yield was 3%. The novel and clean procedure offers advantages including short reaction time, good yield, operational simplicity, and environmentally benign characteristics.

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ISOBAM-104 protected Rh/Ni bimetallic nanoparticles (BNPs) of 3.1 nm in diameter were synthesized by a co-reduction method with a rapid injection of KBH 4 solution. The catalytic activities of as-prepared BNPs for hydrogen generation from hydrolysis of a basic KBH 4 solution were evaluated. Ultraviolet-visible spectrophotometry (UV-Vis), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM) were employed to characterize the structure, particle size, and chemical composition of the resultant BNPs. Catalytic activities for hydrolysis of KBH 4 and catalytic kinetics of prepared BNPs were also investigated. It was shown that Rh/Ni BNPs displayed much higher catalytic activities than that of Rh or Ni monometallic nanoparticles (MNPs), and the prepared Rh 10 Ni 90 BNPs possessed the highest catalytic activities, with a value of 11,580 mol-H 2 ·h −1 ·mol-Rh −1 . The high catalytic activities of Rh/Ni BNPs could be attributed to the electron transfer effect between Rh and Ni atoms, which was confirmed by a density functional theory (DFT) calculation. The apparent activation energy for hydrogen generation of the prepared Rh 10 Ni 90 BNPs was about 47.2 ± 2.1 kJ/mol, according to a kinetic study.

Alloyed Ni/Au/Co nanoparticles with negatively-charged Au, Co atoms, and positively-charged Ni atoms were prepared as effective catalysts for hydrolysis of NaBH4.

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