ActivCRT® and ActivDPF® diesel particulate filters

The CRT®(+) and SDPF™ Diesel Particulate Filter (DPF) passive systems use Johnson Matthey’s Continuously Regenerating Trap (CRT®) technology to effectively reduce particulate matter (PM) and other emissions from stationary diesel engine exhausts.  

Our CRT(+) and SDPF diesel particulate filters are extremely durable systems with advanced filtration and DPF regeneration. By integrating a diesel oxidation catalyst (DOC) with a flow through filter, the oxidation of soot with NO2 occurs at temperatures that are typical of most engine loads.  

These filter systems use an advanced hot exhaust gas filter regeneration process that is simple, reliable, and requires no supplemental heat or fuel. This method also helps to extend engine lifetime and avoids wet stacking.  


Our offer: 

  • Reduces PM by 90+%, hydrocarbons by 70+%, CO by 80+%

  • CRT(+) – CARB (California Air Resources Board) verified for power generators 

  • SDPF, non-CARB verified version  

  • Multiple-filter design fits all engine sizes 

  • SootAlert™ Monitor to ensure operational readiness  



  • Emergency standby, peaking, and prime power generators 

  • ULSD (ultra-low sulfur diesel) or B20 biodiesel fuels 


ActivDPF system 

 Other systems 


Integrated load bank increases engine load 

Filter heated by electrical resistance 

Regeneration mechanism 

Soot reacts with NO2 at lower temperature 

Combustion of soot with O2 at higher temperature 

Energy consumption 

Regeneration requires less energy 

Regeneration requires more energy 

Regeneration frequency 

Only when needed 


Conversion of CO, HC 

ActivDPF converts CO, HC 

No conversion 

Prevent wet stacking to ensure reliable power generation 



Value engineering 

Single load bank shared between multiple gensets 

Regeneration technology required on every single genset 

Cost of ownership 

(capital and operating) 



General enquiries

Joseph McCarney

Betty Ann Keen