2.3.2 Catalytic testing
The activity test was conducted on a continuous flow high-pressure unit
equipped with a stainless-steel fixed-bed tubular reactor with a length
of 1.2 m and an inner diameter of 1 cm with a height of approximately 15
cm. In a typical testing, 10 g of the as-prepared catalyst diluted with
quartz sand of the same size to 12 mL was loaded in the reactor. Both
sides of the catalyst bed were packed with quartz sand. The catalyst was
activated in H2 flow (200 mL min–1and 3 MPa) at 493 K for 24 h at a ramping rate of 10 K
min−1. After being cooled down to the reaction
temperature of 483 K, cyclohexyl acetate was pumped into the reactor at
5.0 g h–1 with the H2/ester molar
ratio of 30 and a system pressure of 5 MPa. The reaction reached the
steady state after 12 h on stream. Then, the product was sampled every
12 h for at least three times, and each sample was analyzed three times
gas chromatographically. The catalysts were evaluated at least in
duplicate.