To further investigate the lifetime and recovery method of catalyst such as AMT / SiO2 calcined at 533K, the results are shown in Figure 2. 

Fig.2 (a) shows that the fresh catalyst maintain a high stability in the first 46h, conversion rate of catechol is more than 95%. With the extension of the reaction time, the catalyst activity decreased slowly, conversion rate of catechol was 95% at 440h, continue to extend the reaction time, the catalyst activity decreased rapidly, conversion rate of catechol has dropped to about 10 % after 550h. The stability of AMT / SiO2 catalyst is lower than aluminum phosphate catalyst system containing titanium of the previous reports, and it is fairly basic to the stability of Zn-Cl2 / Al2O3 catalyst, but much better than some supported catalyst systems such as Cs / SiO2 and so on. The AMT / SiO2 catalyst stability needs to be further improved, but the initial activity and primary product selectivity of the reaction are high. It’s the best single catechol ether and methanol vapor phase reaction reported in the literature.