Synthesis and Application of Fe-MCM-41 Molecular Sieves:Cyclohexane Catalysis Oxidation Into Cyclohexanone

Hexadecyl trimethyl ammonium bromide was employed as template agent,sodium silicate as the silica source and the solution of iron nitrate were added in the synthesis process under 55 ℃,the mesoporous molecular sieve Fe-MCM-41 was synthesized using the hydrothermal method,which was crystallized for 48 hours under 160 ℃.The products were characterized by XRD,nitrogen adsorption and desorption,IR and TG-DTA.The results show that the molecular sieve has the favourable crystal structure and the iron has been located in framework of the molecular sieve.Fe-MCM-41 molecular sieve was used as catalyst and oxygen gas as oxidant for the selective oxidation of cyclohexane.The effects of temperature,time and pressure on cyclohexane selective oxidation reaction were investigated.The conversion of cyclohexane is increased as the increasing of time and temperature, but the pressure has little effect on it.Under the conditions of reaction time being 6 hours,temperature being 180 ℃,and pressure being 2.5 MPa,the conversion of cyclohexane is 14.0%,the selectivity of cyclohexanone is 9.5%,and the selectivity of cyclohexanol is 90.5%.