AbstractFluid ‘hydroforming’ is a powdered catalyst operation that owes its success to continued research and development on naphtha‐upgrading. Its predecessor, fixed‐bed ‘hydroforming’, was employed commercially to make aromatics and aviation gasoline during World War II. The principal reaction occurring is dehydrogenation under pressure in the presence of product gas rich in hydrogen. Like fluid catalytic cracking, it is a regenerative process and can therefore be operated at steady‐state conditions. Among its advantages are superior product distribution, reduced investment and lower operating cost. Fluid ‘hydroforming’ is believed to represent the first successful commercial exploitation of the powdered catalyst technique in a flow system under sub