Catalytic features of Nb-based nanoscopic inorganic fluorides for an efficient one-pot conversion of cellulose to lactic acid

A series of niobium-modified fluorides (denoted Nb@MgF2 and Nb@CaF2), prepared via the fluorolytic solgel synthesis was investigated for the catalytic one-pot conversion of cellulose to lactic acid. In order toestablish the main catalytic features influencing the synthesis of lactic acid, physical-chemical propertiescatalytic performance correlations were made and compared with previously reported Sn@MgF2 and Nb@AlF3 catalysts. The structure of the catalysts is the result of three important parameters: the ionic radiiof the guest-host cations, the fluorolysis rate of each alkoxide species and the concentration of the guestcation. As a function of these parameters samples with different catalytic performances in terms of lacticacid yields are obtained. Nb@CaF2 sample leads to similar yields to lactic acid by comparison with thepreviously reported Nb@AlF3 (15.4% versus 17.0%). In addition, Nb@CaF2 displays a higher hydrothermalstability. (c) 2017 Elsevier B.V. All rights reserved.