The CCR unit is a vital process in a refinery that converts low-octane naphtha into high-octane gasoline blending components, known as reformate. The main purpose of a CCR unit is to increase the octane number of the naphtha fraction without using lead additives.

The principle of CCR is based on catalytic reactions over a platinum-based catalyst, primarily including:

• Dehydrogenation of naphthenes to aromatics – increases octane and produces hydrogen.

• Isomerization of paraffins – improves octane by rearranging straight-chain paraffins into branched forms.

• Hydrocracking and dehydrocyclization reactions – break heavier molecules into lighter high-octane hydrocarbons.

CCR differs from semi-regenerative reformers by allowing continuous catalyst regeneration, meaning the unit does not need to shut down for catalyst replacement or regeneration. This ensures steady production of high-octane reformate and hydrogen, improving overall refinery efficiency.