Process configurations for enhancing light olefin selectivity by steam catalytic cracking of heavy feedstock

A process for upgrading a hydrocarbon feed, the process comprising:

• configuring a steam catalytic cracking reactor in either an ethylene-selective mode or a propylene-selective mode, where configuring the steam catalytic cracking reactor comprises:
• selecting a configuration for the steam catalytic cracking reactor;
• selecting one or more settings for the steam catalytic cracking reactor;
• loading a cracking catalyst based on the one or more steam catalytic cracking reactor settings;
• loading an inert carrier pre-heating into the steam catalytic cracking reactor;
• adjusting a temperature for the steam catalytic cracking reactor based on the one or more steam catalytic cracking reactor settings;
• and
• adjusting a liquid hourly volumetric space velocity for one or more feed pumps in the steam catalytic cracking reactor;
• and
• contacting the hydrocarbon feed with steam in the presence of the cracking catalyst in the steam catalytic cracking reactor at reaction conditions sufficient to cause at least a portion of the hydrocarbons in the hydrocarbon feed to undergo one or more cracking reactions to produce a steam catalytic cracking effluent comprising ethylene, propylene, or both.