The time course of fructose dehydration over Zr-P-Cr catalyst was also recorded and HMF yields at different reaction time points are depicted is .. . It is observed that HMF yield increased with an increase of reaction time, and then it reached the maximum of 86.3% Seeing from ... . HMF yield increased faster at an early reaction stage from 0 h to 1 h. The reason was due to the high concentration of fructose at the early reaction stage. After 2h, HMF yield gradually decreased, and HMF yield decreased to 62.4% after 12h> The blank experiment of the dehydration of fructose with Zr-P as the catalyst only prouced HMF yield in a low yield of 5.6% after 2h (... ,Entry 5). Compared the results obtained from Entry 3 and Entry 5, it can safety conclude that the introduction of Cr in the ZrP-Cr catalyst was the active sites to promote the dehydration of fructose. Prolonging the reaction time of fructose dehydration over Zr-P catalyst to 12 h, HMF yield slowly increased to 24.2% (... , Entry 6). The results on surface of Zr-P also have the ability to catalyze the dehydration of fructose into HMF, but the activity of Zr-P was much weaker than that of Zr-P-Cr.