Study on the Low-Temperature Pre-Desulfurization of Crumb Rubber-Modified Asphalt

Abstract

Waste tires can be ground as crumb rubber (CR) and incorporated into asphalt pavement for efficient resource utilization. However, due to its thermodynamic incompatibility with asphalt, CR cannot be uniformly dispersed in the asphalt mix. In order to address this issue, pretreating the CR with desulfurization is a common way to restore some of the properties of natural rubber. The main technique of desulfurization and degradation is dynamic desulfurization, requiring a high temperature that may lead to asphalt fires, aging, and the volatilization of light substances, generating toxic gases and resulting in environmental pollution. Therefore, a green and low-temperature controlled desulfurization technology is proposed in this study to exploit the maximum potential of CR desulfurization and obtain high-solubility “liquid waste rubber” (LWR) close to the ultimate regeneration level. In this work, LWR-modified asphalt (LRMA) with superior low-temperature performance and processability, stable storage, and less susceptibility to segregation was developed. Nevertheless, its rutting and deformation resistance deteriorated at high temperatures. The results showed that the proposed CR-desulfurization technology could produce LWR with 76.9% solubility at a low temperature of 160 °C, which is close to or even better than the finished products produced at the preparation temperature of TB technology, i.e., 220–280 °C.

Study on the Physical and Rheological Characterisation of Low-Density Polyethylene (LDPE)/Recycled Crumb Rubber (RCR) on Asphalt Binders

“…As shown in Figure 1a, the penetration value of RCRMA is the largest, indicating that CR damages the hardness of the asphalt after pre-treatment, while the added naphthenic oil softens it [20]. The penetration of L-RCRMA showed a decrease compared with that of RCRMA, and with increasing LDPE doping, the penetration of L-RCRMA decreased.…”

“…The asphalt used in the test was 70# A grade matrix asphalt produced by Yunnan Petrochemical (Kunming, China), and all the indices are in accordance with the Technical Specification for Highway Asphalt Pavement Construction JTG F40-2011 the specific properties are shown in Table 4. The DZ catalyst was a mixture of 2,2′-diben zoylaminodiphenyl disulphide (DBD) and zinc oxide (ZnO), which was derived from the group's previous research to be effective in assisting desulphurisation at the ratio deter mined for the test [20].…”

Durability of Polymer-Modified Asphalt Mixture with Wasted Tire Powder and Epoxy Resin under Tropical Climate Curing Conditions

“…Asphalt concrete is a widely used material in road construction due to its excellent properties such as durability, flexibility, and resistance to weathering [1,2]. However, the pavement quality in tropical climate conditions is adversely affected by the frequent cycles of wet and dry conditions during the rainy season, coupled with overloading issues from heavy trucks and traffic congestion [3].…”

Feasibility of Sustainable Asphalt Concrete Materials Utilizing Waste Plastic Aggregate, Epoxy Resin, and Magnesium-Based Additive

“…Among the critical components of infrastructure construction, asphalt concrete plays a pivotal role in providing durable and resilient road surfaces [ 2 ]. Traditional asphalt mixtures primarily consist of aggregates, asphalt binders, and mineral fillers [ 3 ]. However, the environmental impact associated with the extraction of natural aggregates and the disposal of waste materials has prompted researchers to explore innovative approaches for developing sustainable asphalt concrete materials [ 4 ].…”