Study of a Mn–Cr/TiO2 mixed oxide nanocatalyst prepared via an inorganic precursor complex for high-temperature water–gas shift reaction

The influence of three preparation methods on the properties and reaction performances of a titania-supported Mn–Cr bimetallic nanocatalyst for high-temperature water–gas shift reaction has been studied. Impregnation, co-precipitation and thermal decomposition of the [Mn(H2O)6]3[Cr(NCS)6]2·H2O/TiO2 precursor as an inorganic precursor complex were utilized for the preparation of the Mn–Cr/TiO2 catalysts. The calcined catalyst and the precursor that were used for its preparation were characterized by powder X-ray diffraction, scanning electron microscopy, Brunauer–Emmett–Teller specific surface area measurements, thermal gravimetric analysis, differential scanning calorimetry and Fourier transform–infrared spectroscopy. The high-temperature water–gas shift activity was appraised in the temperature range from 280 to 420 °C. The results showed that thermal decomposition of inorganic precursor complexes is more advantageous than impregnation and co-precipitation methods for the preparation of Mn–Cr/TiO2 catalysts for high-temperature water–gas shift reaction.