Dr. Alessandro Mancini, Brembo S.p.A., ITALY

Dr. Sonia Pin, Brembo S.p.A., ITALY

Ms. Bozhena Tsyupa, Brembo S.p.A., ITALY

Dr. Federico Bertasi, Brembo S.p.A., ITALY

Mr. Marco Bandiera, Brembo S.p.A., ITALY

Dr. Matteo Federici, Brembo S.p.A., ITALY

Dr. Andrea Bonfanti, Brembo S.p.A., ITALY

Dr. Guido Perricone, Brembo S.p.A., ITALY

Prof. Ezio Bolzacchini, University of Milano Bicocca, ITALY

Air quality still represents nowadays one of the most challenging problem to be faced from both ecological, health and socio-economical points of view. Centrality of this topic is confirmed from the huge related scientific literature produced as well as the strong legislation activity developed by several national governments and international organizations. Recently, good results in terms of reduction of air pollutants have been achieved. However, particulate matter (PM) is among the air-pollutant categories, the one which is less affected by the adopted countermeasures. In urban areas, significant amount of airborne particulate matter emissions is due to the road transport and are usually divided in the following two categories: i) Exhaust Emissions, referring to particles from combustion; and ii) Non-Exhaust Emissions, indicating particles generated by braking operation, by wear of tyres and roads and by resuspension effects. In recent yers, significant efforts were performed by legislators to reduce exhaust emissions, leading to specific regulations (as for instance EURO Emission Standards). Following the continuous improvement in exhaust treatment technologies, non-exhaust emissions contribute nowadays to the total with similar weight of the exhaust ones. Furthermore, forecasts report that in next the years up to 90% of the total road traffic emissions will arise from non-exhaust sources. With specific reference to non-exhaust emissions, particles generated as primary emission from braking systems are estimated to contribute to the PM10 and PM2.5 blocks respectively by around 50% and 20%. Significant scientific and technological efforts were performed only in the very recent past in order to correlate braking operations and their related particulate emissions, reaching generic understanding on the mechanics and physics involved in the process. In particular, diffuse work has been made in developing robust particles collection protocols and validating reliable analytical methods for determination of particulate number (PN) and mass (PM). However, only limited and very punctual chemical information from few observational studies are available and a complete physico-chemical evaluation of specific emissions from braking operation is still lacking in the current literature. In this contribution, a novel and more complete experimental approach for physico-chemical characterization of brake emissions is presented, including: i) Preparation of an analytical standard simulating brake emission; ii) Calibration of different quantitative analytical techniques for chemical and phase composition detection; and iii) Application of developed analytical protocol on real case sample from dyno-bench test. Particular attention will be paid in extending and deepening the insight on the chemical composition, moving from a standardless approach to the use of external standards for Energy Dispersive X-Ray Spectroscopy (EDXS), X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD) and C,H,N,O-Elemental (EA) analysis. In addition, a closer look into the phase composition will be provided, thanks to the application of the XRD technique. Results reported in the work are meant to provide more reliable and robust chemical tools for bridging the gap between the dimensional characterization of PM from brake emissions and the eco-toxicological studies.