Particle Oxidation Catalyst (POC^®) - From Diesel To GDI - Studies on Particulate Number and Mass Efficiency

Evaluation of the time-resolved nanoparticle emissions and the vehicle performance characteristics for a turbocharged gasoline direct-injection vehicle with a metal-foam gasoline particulate filter

“…The PN reduction was particularly distinct during the ECE-1 cycle, during the EUDC and at aggressive acceleration points, which were mainly due to the oxidation and storage processes of the VOCs and solid particles in the exhaust after-treatment systems. 19,20,23,31–36,41…”

“…To meet the Euro 5 PN and PM mass regulation enacted in September 2011, almost all diesel passenger vehicles have a DPF system installed. 16–23 The PN regulations proposed by the European Union in Euro 6b, which were enacted in September 2014, for GDI engines in light-duty vehicles are 6.0 × 10 12 particles/km, and the regulation in Euro 6c will be strengthened to 6.0 × 10 11 particles/km in September 2017. 20,23–26…”

“…By decreasing the pressure in the GPF, the engine power, the CO 2 emissions, the fuel economy and the filtering performance can be improved in GDI engines. 19,20,31,36,39…”

The Use of a Partial Flow Filter to Assist the Diesel Particulate Filter and Reduce Active Regeneration Events

“…Due to its limited filtration efficiency [3][4][5], the PFF cannot be used as a replacement to the wall flow filter in diesel exhaust as the tailpipe PM emissions would be over the limit imposed by the emission legislation. Nevertheless, these filters still present some advantages over their wall flow counterparts [3] such as lower backpressure increase, no requirement for active regeneration and lower tendency to significantly accumulate lubrication oil ashes. These characteristics lead to less constraints and complexity in terms of filter maintenance and usage which make the PFF an attractive solution to complement and assist the main DPF.…”

“…These characteristics lead to less constraints and complexity in terms of filter maintenance and usage which make the PFF an attractive solution to complement and assist the main DPF. Partial flow filters have already been studied as a retrofit solution for heavy duty vehicles [6][7][8] or possibly fitted in gasoline direct injection (GDI) engine exhaust as a solution for future legislations that impose a limit on particulate mass and number [3,9]. It was also presented as a possible hydrolysis catalyst, positioned upstream of an SCR catalyst [10,11].…”