Catalytic reforming (Platforming) configuration: In modern practice, UOP Platforming units commonly employ which reactor/catalyst handling configuration?

Introduction:
Platforming is UOP’s catalytic reforming technology to upgrade naphtha into high-octane reformate and hydrogen. Reactor configuration and how the catalyst is regenerated affect uptime and severity.

Given Data / Assumptions:

• Feed: desulphurised straight-run naphtha.
• Catalyst: platinum (and bi/tri-metallic) on alumina.
• Reactor trains can be semi-regenerative or continuous catalyst regeneration (CCR).

Concept / Approach:
Historically, semi-regenerative fixed-bed units required periodic shutdowns for regeneration. Modern CCR Platforming uses a moving-bed system that continuously circulates catalyst to a regenerator, enabling higher severity, stable octane, and longer on-stream times. Thus, “moving bed” best describes the prevalent contemporary configuration.

Step-by-Step Solution:

Verification / Alternative check:
Refinery process summaries distinguish semi-regenerative (fixed-bed) versus CCR (moving-bed). Many new installations are CCR for performance and economics.

Why Other Options Are Wrong:

• Fluidised bed: Not the standard for reforming (FCC uses fluidisation).
• Non-regenerative fixed bed only: Outdated as a blanket statement; many units are CCR.
• Regenerative without moving catalyst: CCR regeneration involves catalyst movement.
• Batch stirred tank: Not applicable.

Common Pitfalls:
Confusing FCC fluidised-bed concepts with reforming; ignoring the evolution from semi-regenerative to CCR moving-bed units.

Final Answer:
Moving bed