| dc.description.abstract | This study was to develop a heterogeneous Cu-based catalyst for the hydrogenation of dimethyl adipate (DMA) to hexanediol (HDO). In the past decades, copper-based catalyst has attracted much attention due to its high activity and selectivity in the gas-phase hydrogenation
of esters. In this research, first select some potential catalysts and accelerators based on
literature information, and actually carry out the synthesis of the catalyst. Test the activity of
each synthetic catalyst, and discuss the effect of the accelerator. The catalysts were prepared by
co-precipitation method under different conditions. XRD, TEM, HRTEM, ASAP analysis were
used to characterize the catalyst. Of a wide variety of possible material, manganese is chosen
because it is less by-product produced, toxic-free, weak Lewis acid and high reaction rate of
hydrogenolysis of dimethyl adipate. The Cu-Mn-Al catalyst contains high-content copper and
has a special microstructure. The oxide catalyst is activated with diluted hydrogen gas at a
temperature of 190-230 °C. The copper oxide will be completely reduced to copper and evenly
dispersed in MnO2/Al2O3, which can synthesize nano-level copper catalyst particles and can be
used in many hydrogenation and hydrogenolysis methods. It has with high activity, high
selectivity .The reactions were carried out in a high pressure batch reactor under 90 kg/cm2
and
220 0C. The following preparation parameters were studied: Cu/Mn/Al weight ratios, pH value,
aging time, and calcination temperature. It was found that the catalyst prepared with Cu/Mn/Al
weight ratios 64.3/10/25.7, pH value of 9, and calcination temperature of 750 oC had the highest
conversion rate of 91.3% and the highest hexanediols selectivity of 89.8% among all catalysts. | en_US |