Fluid catalytic reactors which include flow directors

A fluid catalytic reactor comprising:

• a riser comprising a cross-sectional area;
• a lower reactor portion comprising a cross-sectional area;
• a transition portion attaching the riser to the lower reactor portion, wherein the cross-sectional area of the riser is less than the cross-sectional area of the lower reactor portion such that the transition portion is tapered inward from the lower reactor portion to the riser;
• and
• a flow director positioned at least within an interior region of the transition portion, wherein the flow director affects the velocity profile of fluids moving from the lower reactor portion to the riser,
• wherein one or more of:
• the flow director comprises a conical structure;
• the flow director comprises a frustum structure;
• the transition portion comprises a frustum shape;
• or
• the transition portion comprises a conical frustum shape.