A Review of Characteristics of Bio-Oils and Their Utilization as Additives of Asphalts

Abstract

Transforming waste biomass materials into bio-oils in order to partially substitute petroleum asphalt can reduce environmental pollution and fossil energy consumption and has economic benefits. The characteristics of bio-oils and their utilization as additives of asphalts are the focus of this review. First, physicochemical properties of various bio-oils are characterized. Then, conventional, rheological, and chemical properties of bio-oil modified asphalt binders are synthetically reviewed, as well as road performance of bio-oil modified asphalt mixtures. Finally, performance optimization is discussed for bio-asphalt binders and mixtures. This review indicates that bio-oils are highly complex materials that contain various compounds. Moreover, bio-oils are source-depending materials for which its properties vary with different sources. Most bio-oils have a favorable stimulus upon the low temperature performance of asphalt binders and mixtures but exhibit a negative impact on their high-temperature performance. Moreover, a large amount of oxygen element, oxygen-comprising functional groups, and light components in plant-based bio-oils result in higher sensitivity to ageing of bio-oil modified asphalts. In order to increase the performance of bio-asphalts, most research has been limited to adding additive agents to bio-asphalts; therefore, more reasonable optimization methods need to be proposed. Furthermore, upcoming exploration is also needed to identify reasonable evaluation indicators of bio-oils, modification mechanisms of bio-asphalts, and long-term performance tracking in field applications of bio-asphalts during pavement service life.

Revisión sistemática del comportamiento convencional y reológico del biocompuesto asfalto-biomasas producidas

“…Estudiosos analizaron al asfalto PEN 80/100 con adición de residuos de aceite de cocina en 0.2 y 3% determinando que el 2% era la dosis óptima obteniendo 95 de penetración a 25 °C, y al agregar 20, 40 y 60% de aceite de almendra de palma en la mezcla, sólo el 20% promovió la mejora logrando 98 a los 25 °C, siendo el 18.75% y 22.50% de mejora respectivamente [72].…”

Use of bio-binders for asphalt lazers of pavement structures

“…Drugu značajnu grupu čine bio-ulja koja se dobijaju iz biomase biljnog porekla, koja se najčešće dobija kao nusproizvod poljoprivredne proizvodnje [15,16,17] i koja čini oko 60% svih izvora biomase [18].…”

“…Postoji nekoliko tipova pirolize u zavisnosti od temperature i vremena zadržavanja, kao što su brza ili spora piroliza, karbonizacija ili gasifikacija. Za dobijanje bio-ulja se najčešće koristi brza piroliza zbog visoke efikasnosti, jednostavnosti i malih troškova [18].…”

“…Na osnovu pregleda ispitivanja prikazanog u [18], može se zaključiti da sa povećanjem sadržaja bio-ulja na bazi semena palme, od soje, i otpadnog jestivog ulja, dolazi do povećanja penetracije i duktiliteta i smanjenja tačka razmekšavanja bio-veziva.…”

The impact of bio-oil on the structure, rheology, and adhesion properties of lignin-modified asphalt

“…Bio-oils comprised of plant-based pyrolysis oils offer new potential as sustainable modifiers and partial replacements for petroleum-based asphalt [8]. Bio-oils contain lighter fluid fractions similar to maltenes in asphalt, which can supplement the asphalt's fluidity and improve workability and compactability [9]. Research has shown that bio-oils reduce the viscosity-temperature susceptibility of asphalt binders, enhancing performance at cold temperatures [10].…”