Recommendations for handling bitumen prior to FTIR spectroscopy

Abstract

The application of chemical analysis on bituminous materials has increased drastically over the past decades. One of the most common spectroscopic methods used in the field of research is Attenuated Total Reflection (ATR) Fourier Transform Infrared (FTIR) spectroscopy. Since ATR-FTIR is a surface sensitive method, sample or specimen handling of a complex material like bitumen prior to its analysis needs to be considered, especially for people new to the field or analysis technique. This study looks at the impact of heating time and temperature as well as storage time and conditions on the oxidation of the bituminous specimen. Four binders from the same crude oil source but different specification classes (unmodified and styrene–butadiene–styrene polymer modified) and two binders from different crude oil sources were investigated. The results show that heating small quantities of bitumen at 180 °C for up to 30 min has little impact on the formation of oxidized species, when proper thermal monitoring is conducted. Special cases where oxidation does occur are reported in detail. Furthermore, strong oxidation is induced by day light, when bitumen is stored behind glass with no UV radiation present, which can reach short-term ageing level within 1 h. Thus, heating bitumen at 180 °C for 5–10 min followed by storage in the dark, climatized room and measured within one hour after preparation is recommended. These results should act as recommendation for future specimen handling prior to FTIR spectroscopic analysis to ensure unbiased and comparable measurements.

Laboratory Study on Influence of Blending Conditions on Chemo-Thermal Characteristics of Lignin-Modified Bitumen

“…The FTIR spectrum presented in this study was obtained as an average of three (3) replicates. To ensure consistency and comparability, all spectra were normalized to the band with the highest intensity in the bitumen spectrum using a min-max normalization approach [60]. As shown in Figure 9, significant changes observed are between 2000 to 400 cm −1 , which are typically referred to as the "fingerprint region" [61].…”

Analysis and Prediction Model of Styrene-Butadiene-Styrene-Modified Asphalt Aging by Infrared Spectroscopy

“…We refer to Johannes et al’s ( 30 ) recommendations of handling asphalt. The SBS-modified bitumen is heated to a flowing state and poured into a sample bottle (diameter Φ 64 mm × height 140 mm), ensuring the sample mass in the bottle is 35 g ± 0.5 g (as shown in Figure 1).…”

Bio-Polymer Modified Bitumen

“…Fourier Transformed Infrared Spectroscopy (FTIR) was used to study the prevalence of chemical functional groups and possible differences between the pure and blended bitumen samples. FTIR is generally used to identify bitumen ageing behaviour and polymer content of bitumen [17][18][19]. Infrared radiation is used.…”