The document discusses challenges and solutions in refinery process stream purification, particularly focusing on chloride management in catalytic reformers. It highlights problems associated with NH4Cl salt formation and its mitigation strategies, including nitrogen and chloride removal, as well as water injection to prevent plugging, despite its potential to cause HCl corrosion. Various methods and technologies for improving catalyst performance in the refining and petrochemical industries are also explored.

1. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
GBHE Technical Bulletin CTB #52
Catalytic Reforming
Principles & Practices to Manage Chloride on a
Catalytic Reformer Stabilizer
Information contained in this publication or as otherwise supplied to Users is believed to
be accurate and correct at time of going to press, and is given in good faith, but it is for
the User to satisfy itself of the suitability of the information for its own particular purpose.
GBHE gives no warranty as to the fitness of this information for any particular purpose
and any implied warranty or condition (statutory or otherwise) is excluded except to the
extent that exclusion is prevented by law. GBHE accepts no liability resulting from reliance
on this information. Freedom under Patent, Copyright and Designs cannot be assumed.

2. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
Table of Contents
Typical Stabilizer Chloride Management Problems
What Causes NH4Cl Salts?
Mitigating System Fouling
Operating practices
Problems with Water Injection
Design To Mitigate Salt Formation
Prevention
Remove Nitrogen from the feed
Remove chloride from stabilizer feed
Chloride Guard Bed
Caustic Injection
Water Wash
Summary

3. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
Typical Stabilizer Chloride Management Problems
Stabilizer feed system plugging
–Control valves
–Feed/bottoms exchangers
Salt deposits in stabilizer tower
–Reduced tower efficiency
•Off spec product Employ
What Causes NH4Cl Salts?
HCl + NH3 -- NH4Cl
– Chloride injection
• Use to maintain catalyst chloride levels
• Converted to HCl in the reformer
– Nitrogen in hydrotreated feed
• Typical reformer feed specification: 0.5 ppm
• Actual numbers higher
– Up to 2 ppmUpdate
Mitigating System Fouling
Plugging can be alleviated during normal operation
– Water injection
Operating practices
– Inject until evidence of plugging is alleviated
– Slump tower to wash salt deposits

4. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
Problems with Water Injection
Water + HCl -- HCl acid formation
– HCl present in stabilizer feed
– Piping and equipment corrosion
Minimize water injection rate
Design To Mitigate Salt Formation
Prevention
–Remove Nitrogen from the feed
Denitrogenation decreases with decreasing catalyst activity
Increase in reformer feed nitrogen content due to more difficult to treat
hydrotreater feed stock and limited operating severity
–Remove chloride from stabilizer feed
Chloride guard bed ahead of stabilizer tower
Caustic injection/water wash system on stabilizer feed
Feed water wash with overhead neutralization
Chloride Guard Bed
Advantages
– Removal of chloride to specified levels upstream of stabilizer
– Minimal operator monitoring/changes required
Disadvantages
– Cost
– Disposal of spent guard material (waste)
– Polymerization leading to “green oil” fouling
– Difficult to monitor for breakthrough

5. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
Caustic Injection
Advantages
– Minimal new equipment required
– Low cost
– Simple monitoring of effectiveness with pH analysis
Disadvantages
– Operations intensive
– Emulsion problems with over injection or high concentration caustic solution
– If injection is not monitored – plugging and corrosion can occur
Water Wash
Advantages
– Minimal new equipment required
– Simple monitoring of effectiveness with pH analysis
Disadvantages
– Proper design is critical – metallurgy upgrades may be required
– Stabilizer must operate above dew point of water to prevent tower corrosion
– Overhead water wash must force dew point of water such that acid can be
controlled and neutralized

6. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com
Summary
- NH4Cl salt formation resultant of chloride injection and feed nitrogen
- Causes plugging and reduced tower efficiency
- Water injection can reverse the effects of plugging
- Mitigation methods include nitrogen and chloride removal from stabilizer
feed
- Water can be used to prevent salt formation but leads to a secondary
problem: HCl corrosion
- HCl corrosion can be mitigated with chemical injection or metallurgy
upgrades

7. Refinery Process Stream Purification Refinery Process Catalysts Troubleshooting Refinery Process Catalyst Start-Up / Shutdown
Activation Reduction In-situ Ex-situ Sulfiding Specializing in Refinery Process Catalyst Performance Evaluation Heat & Mass
Balance Analysis Catalyst Remaining Life Determination Catalyst Deactivation Assessment Catalyst Performance
Characterization Refining & Gas Processing & Petrochemical Industries Catalysts / Process Technology - Hydrogen Catalysts /
Process Technology – Ammonia Catalyst Process Technology - Methanol Catalysts / process Technology – Petrochemicals
Specializing in the Development & Commercialization of New Technology in the Refining & Petrochemical Industries
Web Site: www.GBHEnterprises.com