Co-SSZ-51 as a catalyst for styrene epoxidation using molecular oxygen

Cobalt substituted SSZ-51 molecular sieve (Co/P molar ratio = 0/0.01/0.05/0.1) samples are synthesized by isomorphic substitution as well as wet impregnation with cobalt salt. The prepared samples are characterized for of their textural and structural properties. The catalytic potential of these samples is investigated for styrene epoxidation in the presence of molecular oxygen at 60 psi. The obtained results showed styrene conversion up to ∼50% with 70–80% selectivity for styrene epoxide till three reaction cycles using Co-substituted SSZ-51 framework. On the other hand cobalt impregnated SSZ-51 samples showed poor selectivity for epoxide (up to 40% only). The obtained results are discussed in terms of cobalt oxidation state present in SSZ-51 framework.