Electronic nose for smart identification of roofing and paving grade asphalt

Asphalt is a complex mixture of hydrocarbons, whose properties strongly depend on the source and type of crude oil and refining processes. From a technical standpoint, intensive investigations carried out by the construction sector, above all by road researchers, have attempted to understand relationships between asphalt binder chemical structure, morphology and physical characteristics. Nevertheless, one challenge that the advance research on asphalt products actually face is to transfer this extremely high level of knowledge to applied industrial technologies for finding easy-to-use, quick and cost-effective test methods for quality control and identification of asphalt binders at refinery, terminal and plant. Thus, this paper focused on the development of a protocol for fingerprinting, including identification and discrimination, of asphalt cements using two different electronic noses (e-noses), also known as artificial olfactory systems (AOS). E-nose is a biomimetic non-destructive intelligent sensing instrument, which is designed to mimic the human sense of smell to detect, compare and classify odor sample, producing a qualitative output (fingerprint). Results suggested that a complementary combination of electronic nose technique and well-established analytical methodologies could be successfully used for the identification and discrimination of roofing and paving grade asphalt cements. Specifically, both sensing instruments were able to perform a good discrimination between products characterized by a different chemical nature and to verify the refinery process stability during production and a batch-to-batch crude oil consistency.