Contributions of Flow Analysis for Quality Control of Automotive Fuels: A Review

Automotive fuels require strict quality control to assure best energy use with minimal environmental pollution. Fuels can be modified before consumption by inadequate transport, storage, and handling, as well as illegal adulteration. Continuous monitoring is of paramount importance to reduce such irregularities, thus requiring reliable analytical methods, which should be simple, fast, and minimize both reagent consumption and waste generation. The potential for in-situ monitoring is also highly desirable. Flow analysis plays an important role in this sense, by means of automated sample processing in closed systems, under highly reproducible conditions. In spite of this potential, application for routine fuel analysis is yet limited and wide dissemination is desirable. This review focuses on analytical approaches for in-line sample pretreatment and determination of organic and inorganic contaminants in automotive fuels by flow analysis. Applications in gasoline, diesel oil, biodiesel, and ethanol fuels are critically discussed.