Mild Hydrothermal Degradation of Cotton Cellulose by using a Mixed‐Metal‐Oxide ZnO–ZrO2 Catalyst

This paper presents a process for the degradation of cotton cellulose in the presence of a mixed‐metal‐oxide ZnO–ZrO2 catalyst under mild hydrothermal conditions (463 K, 1.4 MPa). The main products include glucose, fructose, furfural, 5‐hydroxymethylfurfural (HMF), and water‐soluble oligosaccharides. The highest yield of HMF was 10.05 % at 473 K and the conversion ratio of cotton cellulose reached 81 % at 483 K. The desorption peak in ammonia‐temperature programmed desorption (NH3‐TPD) performed on the ZnO–ZrO2 catalyst was near the 463–473 K range for the degradation of cotton cellulose. The tetragonal phase structure of the ZnO–ZrO2 catalyst played an important role in lowering the temperature and pressure for the hydrothermal degradation of cotton cellulose.