Commissioning and Startup Training Curriculum

Mod 9 - Catalyst & Activation

Module from the Commissioning and Startup Training Curriculum curriculum.

Module 9 — Catalyst Loading and Activation · Learning Objectives · 1. Plan and execute dense, sock, and slurry catalyst loading operations. · 2. Perform reactor loop drying and oxygen removal prior to catalyst introduction. · 3. Execute hydroprocessing catalyst sulfiding (in-situ and ex-situ). · 4. Execute reformer catalyst reduction and isomerization catalyst activation. · 5. Verify activation completeness via DMDS / DMS breakthrough and H2S slip measurements. · Loading Methods

Method	Typical Service	Density Impact
Sock	Small beds, guard bed	~10–15% lower bulk density
Dense (vendor tech)	Main hydroprocessing beds	Reference CBD (vendor)
Slurry	Resid / ebullated beds	Per licensor
Pre-loaded baskets	FCC regenerator internals	N/A
Vacuum loading	Old vessels / inaccessible	Lower than sock
Pre-Load Reactor Preparation
Step	Action
1	Vessel clean, dry, passivated
2	Internals installed, witnessed
3	Scallops, distributors, supports checked
4	Inspection cameras removed; tool count reconciled
5	Inert atmosphere <1% O2 during loading
6	Weigh hoppers calibrated to ±0.1%
7	Loading permit signed; nitrogen breathing air
Sulfiding — Typical Parameters (Hydrotreater)
Parameter	Typical Value
Agent (in-situ)	DMDS (dimethyl disulfide) in LGO carrier
H2S target	2 vol% in recycle before first temp hold
Hold 1	450 °F for 4–6 hr to wet catalyst
Hold 2	550 °F for 4 hr to initiate sulfiding
Hold 3	620 °F for 6 hr full sulfiding
H2S breakthrough	Confirm at recycle gas outlet
DMDS total	Per catalyst vendor, typ. 7–9 wt% on catalyst
Heatup rate	25–50 °F/hr during holds
Reformer Reduction
Parameter	Typical Value
Drying	450 °F under H2 or N2 until H2O <20 ppmv
Reduction gas	H2-rich recycle, low H2O
Target temperature	750–800 °F (Pt/Re catalyst)
Duration	6–8 hr at peak
Water of reduction	Captured on vent analyzer
Chlorine injection	Start during reduction for CCR / SRR catalyst
Activation Acceptance
Catalyst	Indicator
Hydrotreat CoMo/NiMo	H2S slip, delta T across bed, DMDS breakthrough
Hydrocrack NiW	Sulfiding complete; initial WABT per licensor
Reformer Pt/Re	Water of reduction drop to baseline
Isom Pt on chlorided alumina	Cl balance; initial benzene conversion
FCC E-cat	Onstream after hot circulation and flue gas O2 steady
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Source: Commissioning_and_Startup_Training_Curriculum_v1.xlsx · Sheet: Mod 9 - Catalyst & Activation

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