Preparation and Characterization of Ag/SiO2 Catalyst for Dehydrogenation of D-Limonene to p-Cymene

A Silver supported silica catalysts were synthesized by impregnation method using AgNO3 precursor based upon the silica (Aerosil 200, Degussa) support. A defined amount of silver nitrate was dissolved in deionized water. Theamount of precursor was adjusted to yield 2.2 wt.% of Ag in the above mentioned catalyst. This mixture was thenkilned in the furnace at 500◦C under nitrogen atmosphere .The final calcined sample was designed as Agx/SiO2 where x denotes silver loading. For comparison, silica supported catalyst containing 2.2% silver was prepared by impregnation of silica (Aerosil 200, Degussa) with an aqueous solution of silver lactate. Impregnation was followed by drying (313 K, 12 h) and calcination (at 500◦C for 2 h) in the flowing nitrogen. The results revealed that Ag/SiO2 prepared by AgNO3 precursor at 2.2% silver content showed the best activity for selective dehydrogenation of d-limonene to pcymene. Under the optimum conditions, the selectivity of that reaction increases by the time up to 600 minute

کلیدواژه ها:

Dehydrogenation ، precursor ، silver nitrate ، silver lactate ، D-Limonene ، p-Cymene