Rui Chen

Bio: Rui Chen is an academic researcher from Loughborough University. The author has contributed to research in topics: Combustion & Ignition system. The author has an hindex of 32, co-authored 188 publications receiving 3379 citations. Previous affiliations of Rui Chen include Michigan State University & The Chinese University of Hong Kong.

Hydrogen Storage via the Hydrolysis of NaBH4 Basic Solution: Optimization of NaBH4 Concentration

Abstract: Generation of hydrogen via the hydrolysis of sodium borohydride (NaBH4) solution in the presence of metal catalysts is a promising method for hydrogen storage. The concentration of NabH4 should be as high as possible in order to improve energy density. On the other hand, NaBO2 is produced after the hydrolysis of NaBH4. When the NaBH4 concentration is high enough, NaBO2 will precipitate from the solution, which would block the active sites of the catalysts and bring about the complexity of solution transportation. This paper addressed the issue through thermodynamic modeling. A mathematical model was derived first using the equality of chemical potential of the solute in solution and in its solid state. The parameters in the model were determined using phase-diagram analysis and hydration analysis of the NaBH4−NaOH−H2O and NaBO2−NaOH−H2O systems. The optimal concentration of NaBH4 in the hydrogen-generation system was then calculated and a comparison of the modeling results with experimental data, which we...

Review of biodiesel composition, properties, and specifications

Abstract: Biodiesel is a renewable transportation fuel consisting of fatty acid methyl esters (FAME), generally produced by transesterification of vegetable oils and animal fats. In this review, the fatty acid (FA) profiles of 12 common biodiesel feedstocks were summarized. Considerable compositional variability exists across the range of feedstocks. For example, coconut, palm and tallow contain high amounts of saturated FA; while corn, rapeseed, safflower, soy, and sunflower are dominated by unsaturated FA. Much less information is available regarding the FA profiles of algal lipids that could serve as biodiesel feedstocks. However, some algal species contain considerably higher levels of poly-unsaturated FA than is typically found in vegetable oils. Differences in chemical and physical properties among biodiesel fuels can be explained largely by the fuels’ FA profiles. Two features that are especially influential are the size distribution and the degree of unsaturation within the FA structures. For the 12 biodiesel types reviewed here, it was shown that several fuel properties – including viscosity, specific gravity, cetane number, iodine value, and low temperature performance metrics – are highly correlated with the average unsaturation of the FAME profiles. Due to opposing effects of certain FAME structural features, it is not possible to define a single composition that is optimum with respect to all important fuel properties. However, to ensure satisfactory in-use performance with respect to low temperature operability and oxidative stability, biodiesel should contain relatively low concentrations of both long-chain saturated FAME and poly-unsaturated FAME.