Date: December 17, 2013 

To: Brenda Shine, EPA/OAQPS/SPPD 

From: Jeff Coburn 

Subject: Meeting Minutes for December 17, 2013, Meeting Between the U.S. EPA and 

Representatives from Johnson Matthey Intercat Division 

On December 17, 2013, representatives of the U.S. Environmental Protection Agency 

(EPA) and their contractor (RTI International) participated in a meeting with representatives 

from Johnson Matthey’s Intercat division. The purpose of the meeting was to discuss advances 

in fluid catalytic cracking unit (FCCU) catalyst additives to reduce emissions from the FCCU 

catalyst regeneration process since the previous meeting between EPA and Johnson Matthey 

representatives held on October 10, 2012. 

Attendees 

Johnson Matthey Intercat Representatives 

Bart de Graaf, Intercat 

Paul Diddams, Intercat 

U.S. EPA Representatives 

Andrew Bouchard 

Eric Goehl 

Brenda Shine 

RTI International (EPA contractor) 

Jeff Coburn 

Discussion 

Representatives from Johnson Matthey’s Intercat division provided a presentation to 

provide introductory background information and then more detailed research findings. Key 

points discussed during the presentation are summarized below. 

 FCCU coke typically contains 0 to 2 percent nitrogen (N2). At temperatures between 500 

and 700 degrees Celsius (°C), some of this nitrogen will be converted to hydrogen 

cyanide (HCN). Above 700 °C, the coke nitrogen can be converted to nitric oxide (NO). 

Spent catalyst typically returns to the FCCU regenerator at about 500 to 530 °C, so at that 
2

location, HCN formation is favored. The typical dense phase catalyst bed temperature in 

the regenerator is about 730 °C, which favors NO formation. 

 Combustion promoters are used to limit temperature spikes in the FCCU regenerator as 

the gases exit the dense phase (with its higher heat capacity) and travel up to the internal 

cyclones. Combustion of carbon monoxide (CO) in this “light” phase gas can cause 

significant temperature spikes, which can cause metallurgical failure in the regenerator 

and/or cyclones. At some point, adding more combustion promoter will no longer reduce 

CO concentrations in the light gas, but it can increase NO formation. 

 The typical fate of nitrogen in an FCCU regenerator is as follows: 

o No combustion promoter: 80 percent of nitrogen out as N2; 20 percent out as NO. 

o Platinum (Pt) combustion promoter: 20 percent of nitrogen out as N2; 80 percent 

out as NO. 

o Non-Pt combustion promoter: 70 percent of nitrogen out as N2; 30 percent out as 

NO. 

 HCN formation is small compared to NO formation, but significant HCN can be emitted 

from the FCCU regenerator if conditions are favorable to make HCN (i.e., low 

temperatures and high oxygen partial pressure) and conditions are not good to destroy 

HCN that is formed (i.e., HCN formed near the top of the dense phase, so short residence 

time at higher temperatures). According to Intercat representatives, FCCU regenerator 

design is the primary factor influencing HCN emissions and the type of combustion 

promoter used is not a significant factor (both Pt and non-Pt combustion promoters tend 

to reduce HCN formation). 

 Intercat has developed a new catalyst additive called “No NOx.” This additive does not 

have any combustion promotion activities, so it would be used in addition to combustion 

promotion additives. This new additives promotes the reaction of HCN to ammonia 

(NH3), which then reacts with NO to form N2 and water, similar to a selective catalytic 

reduction (SCR) control system. Commercial production of this “No NOx” additive is in 

the early stages; no commercial units are currently using this additive. 

 Intercat also makes a series of catalyst additives to reduce sulfur oxide (SOx) emissions 

from the FCCU regenerator. These additives catalyze the oxidation of sulfur dioxide 

(SO2) to sulfur trioxide (SO3) and use a metal carrier to effectively absorb the SO3. The 

metal carrier is effectively regenerated in the riser section of the FCCU, where the SO3 is 

released and converted to hydrogen sulfide (H2S), which can be recovered and treated in 

the sulfur recovery plant. At low riser temperatures (e.g., those used when making diesel 

fuel rather than gasoline), the metal carrier will not release all of the SO3 (i.e., will not be 

regenerated in the riser), leading to diminished effectiveness of the additive system. New 

SOx additive products have been developed to work at lower riser temperatures, so it is 

possible to get good performance when FCCU are run in distillate mode. Also, normal 

SOx additives are not effective for FCCU that operate in partial burn mode. Intercat has 

developed a new catalyst additive that can achieve some SOx emission reduction for 

partial burn FCCU.