The present disclosure provides a process for preparing a conjugated diene from a C4. feed; said process comprising contacting said C4 feed with at least one catalyst selected from the group consisting of oxides of Gr. IIB metals and Gr. VIII metals under a set of pre-determined dehydrogenating conditions followed by passing at least one oxygenate selected from the group consisting of steam, carbon dioxide (CO2), oxygen, carbon monoxide through the C4 feed to obtain the conjugated diene.