New Atomic Absorption Methods for Metals Determination in Aviation and Automotive Gasoline

New methods for direct atomic absorption determination of lead and lithium as antiknock additives components in aviation and automotive gasoline in the concentration ranges 100–1700 (Pb) and 2.5/0.25–100 (Li) mg/L have been developed. To overcome the difference in analytical signals for samples and standard solutions due to concentration values and matrix effects the proper sample dilution and the addition of the blank as pure reagent hydrocarbons mixture in the solutions have been offered. The methods have high precision, are simple and may be recommended for gasoline quality control and identification procedures.

Evaporative Emissions From Automotive Gasoline Fuel Tank Refueling: Experimental Activity and Numerical Simulation

Vehicle evaporative emission is one of the most important sources of pollution from a gasoline-fueled vehicle. Since international regulations on Volatile Organic Compounds (VOC) emission are becoming increasingly stringent every year, the study of the VOC generation has become of fundamental importance. It is known that VOC generation is particularly high during the refueling phase: fresh fuel coming from the refueling nozzle impacts on the filling pipe wall and it is a source for sloshing in the fuel tank. Fuel vapor generated can be collected by a vapor recovery nozzle and stored in the gas station tank (Stage II vapor recovery system, European normative) or trapped by the vehicle carbon canister (On-board Refueling Vapor Recovery system, U.S. normative). In this activity, an automotive gasoline fuel tank for U.S. applications has been used for both experimental and numerical analyses, provided by FCA. Experiments were performed in FCA laboratories, in a sealed and thermal controlled environment (mini-SHED): vapor flow exiting the fuel tank during refueling has been measured, and fuel vapor mass has been evaluated by dynamically measuring the weight variation of a carbon canister filter connected to the fuel tank vent system. A CFD model was built based on CAD geometries provided by FCA, and numerical analysis of the refueling process has then been executed by using a commercial 3D CFD software. Results were then compared with experimental data. This activity is a part of a collaboration between University of Naples Federico II and FCA Italy about fuel vapor emissions control and prediction.