This study explores the potential of oil sludge, a hazardous by-product of the oil industry, as a sustainable rejuvenator for restoring the physicochemical and rheological properties of aged bitumen. Aged binder samples were modified with different concentrations of oil sludge (1%, 3%, and 5%) and analyzed using dynamic shear rheometry (DSR), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The incorporation of 5% oil sludge increased penetration from 60 to 71 mm and the softening point from 55 °C to 72 °C, indicating enhanced flexibility. DSR measurements showed a ~10% decrease in complex modulus (G*) and a slight increase in phase angle, confirming partial rheological recovery. FTIR spectra revealed partial restoration of aliphatic and aromatic functional groups, with a decrease in sulfoxide absorption bands, while SEM analysis indicated improved homogeneity and reduced microcracking. TGA confirmed enhanced thermal behavior and a reduction in residual mass. The novelty of this work lies in the first-time application of regionally sourced oil sludge as a rejuvenator, evaluated through a multiscale analytical framework. These findings demonstrate the dual benefits of performance recovery and hazardous waste valorization, contributing to sustainable road maintenance within a circular economy approach.

Recycling reclaimed asphalt pavement fulfills an important function in achieving a sustainable and environmentally friendly road construction industry. Using reclaimed asphalt pavement (RAP) it is possible to produce new asphalt with a small amount of virgin raw materials. This will reduce the amount of energy required to extract and process virgin asphalt pavement materials, along with the amount of waste generated during road reconstruction. Despite these advantages, road agencies have been reluctant to use high proportions of RAP materials in new asphalt production because the presence of large amounts of oxidized bitumen from RAP in new mixtures makes them less workable and less compactable than mixtures with virgin bitumen alone. One should also be aware of the high stiffness of RAP mixtures, which will make them difficult to use. Various methods can be used to overcome this problem, one of the most effective is the addition of rejuvenating agents. This article describes research into the production of asphalt mixtures from recycled asphalt pavement (RAP) material. This work aims to study the effectiveness of various rejuvenators for restoring the basic performance characteristics of asphalt pavements. The most effective rejuvenators and their classification are reviewed. The hypothesized mechanism of rejuvenation of asphalt pavements by the introduction of rejuvenators is presented. The methods of introducing various rejuvenators into RAP are described.

One of the problems of the paper industry is the search for raw materials. Due to the depletion of non-renewable resources, the role of recycling waste paper, which makes up about 7% of solid municipal waste and contains valuable cellulose, is growing. In developed countries, millions of tons of paper packaging are produced annually, creating large volumes of waste paper [1].Paper recycling plays a significant role in reducing environmental impacts, reducing waste volumes and minimizing the use of primary resources. However, despite advances in paper recycling, the problem of cleaning up contaminants such as chemicals, paints and pigments remains relevant. These contaminants reduce the quality of recycled material and increase the complexity of the production process. This article reviews modern paper cleaning methods such as the use of surfactants, chemical reagents and combined approaches to improve recycling efficiency. In this study, a set of chemical reagents including sodium dodecyl sulfate (SDS) and sodium hypochlorite were selected to evaluate their impact on paper cleaning. To evaluate the efficiency of waste paper cleaning, physicochemical methods including UV spectroscopy, IR spectroscopy, thermogravimetric analysis and differential thermal analysis were used, which provided comprehensive information on the composition and changes in the material during processing.