Search

Abstract: Weakly magnetic CaFe2O4 was synthesized by calcination of the hydroxides co-precipitated from aqueous Ca(NO3)2·6H2O and Fe(NO3)3·9H2O solutions in the presence of urea. Microcrystalline cellulose was treated with ionic liquid (IL) [AMIM]Cl (1-allyl-3-methylimidazolium chloride) and hydrolyzed in the presence of the catalyst at 423K. No IL contamination was detected in the treated cellulose by energy-dispersive X-ray spectrometry (EDX). A maximum hydrolysis yield of 49.8% and glucose selectivity of 74.1% was obtained. The catalyst was separated and reused four times, showing only a slight decrease in activity. The catalyst was stable and only minor leaching into water occurred as indicated by inductively coupled plasma atomic emission spectrometry (ICP), X-ray diffraction (XRD), and temperature programmed desorption (TPD) measurements and a neutral pH after reactions. Hydrolysis of cellulose with CaFe2O4 catalyst combined with [AMIM]Cl pretreatment is a green, energy-saving and efficient process. [Copyright &y& Elsevier]

Hydrotalcite nanoparticles were synthesized by co-precipitation of aqueous Mg(NO(3))(2)·6H(2)O and Al(NO(3))(3)·9H(2)O in the presence of urea and subsequent microwave-hydrothermal treatment. The nanoparticles were activated with saturated aqueous Ca(OH)(2), and used to hydrolyze cellulose. A maximum hydrolysis yield of 47.4% with high glucose selectivity (85.8%) was achieved at 423 K. The nanocatalyst was stable and leached little as confirmed by ICP, XRD, and neutral effluent aqueous solution after reactions. It can be concluded that hydrotalcite nanoparticles activated with Ca(OH)(2) were a highly active, selective and stable catalyst for hydrolysis., (Copyright © 2011 Elsevier Ltd. All rights reserved.)