Composite coatings containing brushite (CaHPO4 · 2H2O) and chitosan were prepared by electrochemical deposition. The brushite/chitosan composites were converted to hydroxyapatite/chitosan composites in aqueous solutions of sodium hydroxide. The coatings ranged from ≈1 to 15% chitosan by weight. Qualitative assessment of the coatings showed adhesion significantly improved over that observed for electrodeposited coatings of pure HA. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 66A: 411–416, 2003

This work focuses on optimizing the performance of a Ni/SiO 2 -Al 2 O 3 adsorbent for the adsorptive desulfurization of jet fuel, including JP-8 jet fuel containing around 736 ppmw sulfur and a light JP-8 jet fuel having around 380 ppmw sulfur, obtained by fractionation for micro solid oxide fuel cell applications. The fractionated light JP-8 jet fuel had only traces of heavier alkylated benzothiophenes (C3-BTs). The removal of C3-BTs such as sterically hindered 2,3, 7-trimethylbenzothiophene from the JP-8 jet fuel by fractionation improved the adsorbent capacity by 2.5 times. The particle sizes of the adsorbent and its bed dimensions were examined and optimized to achieve targeted sulfur adsorption capacity of over 10 mg of S/g of adsorbent without encountering pressure drop across the bed. The adsorptive desulfurization of fractionated light JP-8 over the Ni/SiO 2 -Al 2 O 3 adsorbent having particle sizes between 0.15 and 0.25 mm offered a sulfur breakthrough adsorption capacity of about 11.5 mg of S/g of adsorbent without developing any significant pressure drop across the beds. High sulfur-adsorption capacity could be achieved with Ni/SiO 2 -Al 2 O 3 when the overall aspect ratio, axial aspect ratio, and radial aspect ratio of the adsorbent bed were around 60, 3000, and 100, respectively.

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