Taken from the Green car website, I have just read about Citroen/Peugeots successful emission control device, which has now proven to reduce Nitrous oxide by 90% to levels similar to a petrol powered car. Full story:
PSA Peugeot-Citroën reports that initial tests show that the BlueHDi after-treatment system, used on the company's latest generation of efficient diesel engines is compliant with Euro 6 regulations and are aligned with homologated data.
The tests, which were organised by the French Ministry of Ecology, Sustainable Development and Energy on the Peugeot 208 and Peugeot 508 models, confirm the effectiveness of the after-treatment system in which Selective Catalytic Reduction (SCR) technology is positioned upstream of the particulate filter to eliminate up to 90% of the nitrogen oxides (NOx) released by diesel engines and bring NOx emissions down to levels near those of petrol engines.
BlueHDi involves a three stage cleansing process which specifically targets diesel emissions. In stage one, the oxidation catalytic converter eliminates the hydrocarbons (HCs), transforming them into water (H2O) and carbon dioxide (CO2); stage two sees the SCR transform the nitrogen oxides (NOx) into water and nitrogen (N2), the main constituent of air (78%), with the addition of AdBlue® (a mixture of urea and water); and in stage three, a particulate filter reduces the particulates by number by over 99%.
Convinced by SCR's potential, PSA Peugeot-Citroën developed and invested in BlueHDi for deployment in 2013, two years before mandated by regulations. The system was then gradually added as standard equipment on all Euro 6-compliant diesel models. Due to its effective use of SCR technology, the Peugeot 208 1.6 BlueHDi won Next Green Car's Supermini 2015 Award.
PSA Peugeot-Citroën has filed some one hundred patents for BlueHDi technology, which has undergone continuous development with a view to improving performance and cost in time for the new Euro 6.2 emissions standards in September 2017.
The company claims that the latest tests also show that diesel engines maintain their advantage of 15% lower CO2 emissions and 20% greater fuel efficiency.
In addition to diesel power units, Peugeot-Citroën offer line-up of high-performance petrol engines, including the 3-cylinder PureTech (2015 "International Engine of the Year"), which is recognised for its high fuel efficiency and low CO2 emissions. The Group is also currently developing its second generation of electric vehicles, as well as a new range of plug-in petrol hybrids for launch in 2019.
- See more at:
Tests confirm effectiveness of PeugeotCitron BlueHDi system | Next Green Car
There's also a simplified YouTube video briefly explaining the step by step process here
https://www.youtube.com/watch?v=mTCqjnmBtE8
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