Synthesis Of Carbon Monoliths And Their Catalytic Performance For Benzyl Alcohol Oxidation

Carbon monoliths not only have the excellent properties of antacid alkali resistance, high thermal stability, good chemical stability, also have a unique structure and high ratio of surface area to volume. They have been widespread applied in many fields, such as catalyst support, electrode material, adsorbent and etc. The preparation methods for carbon monoliths include sol-gel method, CVD, machining methods. The great challenge is to synthesize carbon monoliths which have good mechanical properties, low pressure, and simply synthesis process.1) According the carbon monoliths which prepared by sol-gel method prone to bending rupture and have high pressure drop, a new carbon monoliths having intact exterior were synthesized by changing the skeletal structure. The monoliths have 3D hierarchical porous structure. By investigating the amount of solid content, block copolymers, reaction time and other factors, we achieve the control of macropores. The carbon monoliths with large pore size 5.1?m have low pressure drop and high mechanical strength, which only have 0.04MPa/cm pressure drop if the gas flow is 100mL/min, and the axial mechanical strength up to 4.94MPa.2) The obtained carbon monoliths have three-dimensional interconnected pore structures. Mass transfer was accelerated because of the structure which has macropores provided channels for liquid flow, micropores guaranteed high ratio of surface area to volume and mesopores connected macropores and micropores. The monolithic reactor has low pressure drop and good mechanical strength, which can be applied for the reaction of benzyl alcohol oxidation. The results showed that the conversion of benzyl alcohol up to 50%, residence time 15min and overall mass transfer coefficient 4.829×104 m/s in the conditions of oxygen flow for 11mL/min, liquid flow of 30?L/min, reaction temperature of 80?. During the reaction, liquid membrane was formed on the macropore surfaces.