Many industrial sectors exploit fossil sources to develop useful and necessary materials for our needs,such as bituminous paving materials.Bitumen,a key component of asphalt mixtures,is derived from oil refining and i...Many industrial sectors exploit fossil sources to develop useful and necessary materials for our needs,such as bituminous paving materials.Bitumen,a key component of asphalt mixtures,is derived from oil refining and its properties are influenced by the crude oil source and refining process,resulting in a significant carbon footprint.With growing awareness of resource depletion and environmental concerns,pavement researchers are exploring sustainable alternatives to reduce dependence on fossil sources.This includes a rising trend in using renewable materials like biomasses to produce bio-based binders as substitutes for bitumen,aiming for a more sustainable approach.Biomasses,including vegetal and animal wastes,and waste cooking oils,as substitutes for crude oil in the production of bio-binders.Through thermochemical conversion(TCC),such as pyrolysis,biomasses can be converted into bio-char and bio-oils,which can replace fossil-based components in binders.Researchers have utilized these bio-products to reduce the dependency on fossil fuels in binders.However,there are no set minimum requirements for bio-components in bio-based binders.As the percentage of replaced bitumen increases,various types of binders are produced,including modified bitumen,extended bitumen,and alternative binders,where the fossil replacement is gradual.Overall rheological tests on bio-binders,reveal that those containing biochar exhibit increased viscosity,stiffness,rutting resistance,and sometimes antioxidant properties.Conversely,bio-binders with bio-oils as bitumen substitutes show poorer performance at high temperatures but improved behavior at low temperatures.These results suggest that bio-binders could provide versatile solutions for various climatic and loading conditions in road construction.However,the development of pavement mixtures based on bio-binders has not been studied in depth and requires further attention to unlock its full potential.As sustainability considerations,including life cycle assessments(LCA)and life cycle cost analyses(LCC),are crucial aspects for future studies.It is essential not only to collect data on the performance characteristics of bio-binders but also to understand their environmental impact and recyclability.In-depth evaluations using methods such as LCA and LCC will provide valuable insights into the overall sustainability and long-term viability of these products.展开更多
To promote the application of bio-materials and provide a direction for their further researches,this paper comprehensively summarizes the research progress of biomaterials in recent years.The review results show that...To promote the application of bio-materials and provide a direction for their further researches,this paper comprehensively summarizes the research progress of biomaterials in recent years.The review results show that bio-oil is a mixture obtained from different biomasses through pyrolysis,alcoholysis,acidolysis,high liquefaction,etc.,and those biomasses mainly include wood fiber type,waste oil type and animal manure type.Biobinder refers to the product of bio-oil processed by distillation,extraction oxidation and polymer modification,and it can be served as a modifier,diluent or substitute material of asphalt;the main chemical components of bio-oil include ethers,esters,aldehydes,ketones,phenols,organic acids,alcohols and sugars.Bio-asphalt is obtained by adding biobinder into the petroleum asphalt for modification or blending,and the shear temperature and shear rate of bio-asphalt derived from wood fiber type and waste oil type are usually higher than that of bio-asphalt derived from swine manure.Compared with petroleum asphalt,bio-asphalt binder usually shows lower high-temperature performance as well as higher low-temperature performance and aging resistance.Also,bio-asphalt mixture generally exhibits lower high-temperature stability,higher low-temperature crack resistance and water stability than petroleum asphalt mixture.Future studies should be conducted combining with the source,composition,preparation,properties and oil production rate of bio-oil.First,how to raise the bio-binder content in bio-asphalt as much as possible while ensuring the sufficient performance becomes the focus of future researches.Second,the micro reaction mechanism between bio-binder and petroleum asphalt should be illustrated in depth.Moreover,developing a complete and unifying technical standard and application specification of bio-asphalt technology is necessary for future researches.Furthermore,determining the optimum bio-binder potentially used as the substitute of petroleum asphalt is also an interesting topic.展开更多
Nowadays,sustainability and circular economy are two principles to be pursued in all fields.In road pavement engineering,they can be put into practice through the partial substitution of bitumen with industrial residu...Nowadays,sustainability and circular economy are two principles to be pursued in all fields.In road pavement engineering,they can be put into practice through the partial substitution of bitumen with industrial residues and by-products deriving from renewable materials.Within this framework,this paper presents an extensive investigation of the chemical,morphological and rheological properties of bio-binders obtained by mixing a conventional 50/70 bitumen with different percentages by weight(0,5%,10%and 15%)of a renewable bio-oil,generated as a residue in the processing of wood into pulp and paper.Results show that overall the bio-oil provides a softening effect,which,in terms of performance,leads to an improvement of the low-temperature behaviour and fatigue resistance with respect to the control bitumen,in spite of an increased tendency to permanent deformation.Although no chemical reaction appears to occur after blending,the peculiarities of the bio-oil affect the chemistry of the resulting bio-binders,whereas no phase separation is observed from the microscopic analysis.In addition,a Newtonian behaviour,an unchanged temperature susceptibility and a good fitting of 1 S2 P1 D model to the rheological data are found,regardless of the bio-oil percentage considered.These promising outcomes suggest that such bio-binders can be favourably employed for several applications in road pavements.展开更多
The use of alternative renewable sources to totally or partially replace bitumen is one of the most current challenges in the road pavement sector.The growing energy cost and environmental concerns lead to the necessi...The use of alternative renewable sources to totally or partially replace bitumen is one of the most current challenges in the road pavement sector.The growing energy cost and environmental concerns lead to the necessity to find alternative solutions,by supporting at the same time sustainability and circular economy principles.Within this framework,this paper presents the application of a powder lignin,a natural bio-polymer deriving from byproducts of wood pulp and paper industry,to replace part of bitumen.The bituminous blend consisting in 70%of bitumen and 30%of powder lignin(by weight)was made in laboratory through the use of a high shear stirring mixer,and a reference plain bitumen characterized by a similar consistency(i.e.,same penetration grade)was used as comparison.Then,an extensive investigation on chemical and rheological properties of the bio-binder is presented.Fourier transform infrared spectroscopy(FTIR),saturates,aromatics,resins and asphaltenes(SARA),bending beam rheometer(BBR),frequency sweep tests and multiple stress creep recovery tests(MSCR)with a dynamic shear rheometer(DSR)were performed.Moreover,unaged,short-and long-term aging conditions were considered.Results indicated that powder lignin dominates the rheological behavior of the bio-binder and,from chemical analysis,it seems that it partially acts as a filler and partially as a binder.This would result in improved performances at both low and high temperatures,leading to a wider temperature range of performance grade(PG).Moreover,despite a stiffening effect is recognized,lignin also offers an antioxidant potentiality,reducing the aging susceptibility of the investigated bio-binder.展开更多
基金The research is funded by the NEXT GENERATION EU–PNRR project ex D.M.352/2022.The authors would like to thank ENI S.p.A for supporting this research.
文摘Many industrial sectors exploit fossil sources to develop useful and necessary materials for our needs,such as bituminous paving materials.Bitumen,a key component of asphalt mixtures,is derived from oil refining and its properties are influenced by the crude oil source and refining process,resulting in a significant carbon footprint.With growing awareness of resource depletion and environmental concerns,pavement researchers are exploring sustainable alternatives to reduce dependence on fossil sources.This includes a rising trend in using renewable materials like biomasses to produce bio-based binders as substitutes for bitumen,aiming for a more sustainable approach.Biomasses,including vegetal and animal wastes,and waste cooking oils,as substitutes for crude oil in the production of bio-binders.Through thermochemical conversion(TCC),such as pyrolysis,biomasses can be converted into bio-char and bio-oils,which can replace fossil-based components in binders.Researchers have utilized these bio-products to reduce the dependency on fossil fuels in binders.However,there are no set minimum requirements for bio-components in bio-based binders.As the percentage of replaced bitumen increases,various types of binders are produced,including modified bitumen,extended bitumen,and alternative binders,where the fossil replacement is gradual.Overall rheological tests on bio-binders,reveal that those containing biochar exhibit increased viscosity,stiffness,rutting resistance,and sometimes antioxidant properties.Conversely,bio-binders with bio-oils as bitumen substitutes show poorer performance at high temperatures but improved behavior at low temperatures.These results suggest that bio-binders could provide versatile solutions for various climatic and loading conditions in road construction.However,the development of pavement mixtures based on bio-binders has not been studied in depth and requires further attention to unlock its full potential.As sustainability considerations,including life cycle assessments(LCA)and life cycle cost analyses(LCC),are crucial aspects for future studies.It is essential not only to collect data on the performance characteristics of bio-binders but also to understand their environmental impact and recyclability.In-depth evaluations using methods such as LCA and LCC will provide valuable insights into the overall sustainability and long-term viability of these products.
基金supported by the Key Research and Development Program of Shaanxi Province(Grant No.2022SF-169)。
文摘To promote the application of bio-materials and provide a direction for their further researches,this paper comprehensively summarizes the research progress of biomaterials in recent years.The review results show that bio-oil is a mixture obtained from different biomasses through pyrolysis,alcoholysis,acidolysis,high liquefaction,etc.,and those biomasses mainly include wood fiber type,waste oil type and animal manure type.Biobinder refers to the product of bio-oil processed by distillation,extraction oxidation and polymer modification,and it can be served as a modifier,diluent or substitute material of asphalt;the main chemical components of bio-oil include ethers,esters,aldehydes,ketones,phenols,organic acids,alcohols and sugars.Bio-asphalt is obtained by adding biobinder into the petroleum asphalt for modification or blending,and the shear temperature and shear rate of bio-asphalt derived from wood fiber type and waste oil type are usually higher than that of bio-asphalt derived from swine manure.Compared with petroleum asphalt,bio-asphalt binder usually shows lower high-temperature performance as well as higher low-temperature performance and aging resistance.Also,bio-asphalt mixture generally exhibits lower high-temperature stability,higher low-temperature crack resistance and water stability than petroleum asphalt mixture.Future studies should be conducted combining with the source,composition,preparation,properties and oil production rate of bio-oil.First,how to raise the bio-binder content in bio-asphalt as much as possible while ensuring the sufficient performance becomes the focus of future researches.Second,the micro reaction mechanism between bio-binder and petroleum asphalt should be illustrated in depth.Moreover,developing a complete and unifying technical standard and application specification of bio-asphalt technology is necessary for future researches.Furthermore,determining the optimum bio-binder potentially used as the substitute of petroleum asphalt is also an interesting topic.
文摘Nowadays,sustainability and circular economy are two principles to be pursued in all fields.In road pavement engineering,they can be put into practice through the partial substitution of bitumen with industrial residues and by-products deriving from renewable materials.Within this framework,this paper presents an extensive investigation of the chemical,morphological and rheological properties of bio-binders obtained by mixing a conventional 50/70 bitumen with different percentages by weight(0,5%,10%and 15%)of a renewable bio-oil,generated as a residue in the processing of wood into pulp and paper.Results show that overall the bio-oil provides a softening effect,which,in terms of performance,leads to an improvement of the low-temperature behaviour and fatigue resistance with respect to the control bitumen,in spite of an increased tendency to permanent deformation.Although no chemical reaction appears to occur after blending,the peculiarities of the bio-oil affect the chemistry of the resulting bio-binders,whereas no phase separation is observed from the microscopic analysis.In addition,a Newtonian behaviour,an unchanged temperature susceptibility and a good fitting of 1 S2 P1 D model to the rheological data are found,regardless of the bio-oil percentage considered.These promising outcomes suggest that such bio-binders can be favourably employed for several applications in road pavements.
文摘The use of alternative renewable sources to totally or partially replace bitumen is one of the most current challenges in the road pavement sector.The growing energy cost and environmental concerns lead to the necessity to find alternative solutions,by supporting at the same time sustainability and circular economy principles.Within this framework,this paper presents the application of a powder lignin,a natural bio-polymer deriving from byproducts of wood pulp and paper industry,to replace part of bitumen.The bituminous blend consisting in 70%of bitumen and 30%of powder lignin(by weight)was made in laboratory through the use of a high shear stirring mixer,and a reference plain bitumen characterized by a similar consistency(i.e.,same penetration grade)was used as comparison.Then,an extensive investigation on chemical and rheological properties of the bio-binder is presented.Fourier transform infrared spectroscopy(FTIR),saturates,aromatics,resins and asphaltenes(SARA),bending beam rheometer(BBR),frequency sweep tests and multiple stress creep recovery tests(MSCR)with a dynamic shear rheometer(DSR)were performed.Moreover,unaged,short-and long-term aging conditions were considered.Results indicated that powder lignin dominates the rheological behavior of the bio-binder and,from chemical analysis,it seems that it partially acts as a filler and partially as a binder.This would result in improved performances at both low and high temperatures,leading to a wider temperature range of performance grade(PG).Moreover,despite a stiffening effect is recognized,lignin also offers an antioxidant potentiality,reducing the aging susceptibility of the investigated bio-binder.
