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As vehicles are on the rise globally, so is tire disposal when out of service. One potential recycling process is turning the waste tire into a useful composite by incorporating it with thermoplastic materials. In the present work, composite based on waste tire rubber (WTR) and polypropylene (PP) were developed using a single screw filament extruder for various concentrations of WTR (20, 40, 60, and 80% wt.). Physical and morphological characterization of WTR (425 µm) and WTR-PP composite was performed; furthermore, mechanical characterization of WTR-PP composites was also carried out under the tensile load. Morphological observation reveals that WTR-PP with low WTR content shows comparatively better distribution, maintaining the necessary strength and thermoplasticity of the composite compared to the higher WTR content in the composite. The tensile study shows that incorporating WTR with polypropylene decreased tensile strength but improved elongation at break. The macrofractography is carried out to study the failure origin and crack propagation in the WTR-PP composite. [ABSTRACT FROM AUTHOR]

The technological evolution of electronic equipment in the field of computers and household appliances, along with shorter life of most items, is creating a great concern for managing this waste stream. The main aim of the present investigation was to convert waste keyboard keys into high-quality pyrolysis oil using a microwave catalytic pyrolysis process. Iron (Fe), Nickel (Ni), were doped in different ratios on Biochar (BC) by wet impregnation method, and it was used as a green catalyst for clean fuel production. Initially, a non-catalytic pyrolysis process was conducted and found a maximum pyrolysis oil yield of 49.6 wt.%. Further, microwave catalytic pyrolysis was conducted with variable amount of metal loading and found that highest oil yield of 61.33 wt.% was achieved using 15%Fe-5%Ni/BC catalyst due to the presence of a higher quantity of iron. The produced pyrolysis oil at this condition consists of 45.07% single-ring compounds and reduced the undesirable polycyclic aromatic hydrocarbons (PAHs) in the pyrolysis oil. This work provides a pathway for preparing green catalysts and safe disposal of electrical and electronic plastic waste with better resource recovery. [ABSTRACT FROM AUTHOR]

Within the scope of end-of-life tires (ELTs) management, recovery of tires considering circular economy approach is becoming increasingly important. This study aims to examine the sorptive behavior of methylene blue (MB) and Rhodamine B (RB) dyes from synthetic textile industry discharge with a carbon-based sorbent (CBM) recycled from ELTs as a novel patented method and used for the first time for organic dye removal in the literature. The CBM was characterized by using fourier transform infrared (FTIR) and scanning electron microscopy (SEM) for structural and morphological properties. XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy) analysis were used for phase composition and surface chemistry of CBM. The maximum adsorption capacity of MB and RB on CBM is 681.14 and 85.26 mg/g, respectively. For the reusability of the CBM, the regeneration experiment was carried out and MB and RB removal performance of CBM gradually decreased with increasing adsorption cycles. The results show that it is possible to utilize CBM which in terms of ensuring the reuse of wastes within the scope of industrial symbiosis, as an effective adsorbent in dye removal. This study reduces environmental pollution by converting the end-of-life tires into carbon-based material for water/wastewater treatment provides a "win-win" solution to improve waste management. [ABSTRACT FROM AUTHOR]

The two-stage technology of porous carbonaceous material obtained via pyrolysis in inert medium with subsequent activation by steam is well known. While steam could be a suitable substance for pyrolysis as well, single-staged technology for waste tire recycling is yet to be developed. A comparative analysis of the characteristics of the carbonaceous materials obtained by the single-staged steam pyrolysis of waste tires was carried out, which could provide a theoretical background for the development of such technology. The steam pyrolysis was performed in a tubular reactor in an overheated steam medium (500°C with 5 kg/h mass flow rate). The technical characteristics of the obtained samples were evaluated in the context of their potential for further application as absorbent and raw material for rubber production according to Chemical Abstracts Service No. 1333–86-4. The composition and physico-chemical properties of the obtained samples were studied using BET and thermogravimetric analysis, atomic emission, transmission and scanning electron microscopies, Raman, X-ray diffraction, and photoelectron spectroscopies. The results revealed that the structure and properties of all obtained carbonaceous material samples were similar. The samples consisted of amorphous carbon (with a disordered graphite lattice) and contained a significant amount of metal oxides. According to experimental data, zinc was present in the form of ZnO with a binding energy of 1022.4 eV, while sulfur was observed in the form of sulfide and oxysulfide with binding energies of 161.8 and 163.2 eV, respectively. According to electron microscopy, the morphology of samples was represented by a set of spherical agglomerates comprising nanosized particles. According to the BET analysis of the samples, the specific surface area varied in the range between 52.0 and 66.0 m2/g and the pore volume values were within a range of 0.53–0.87 cm3/g, while the average pore size varied from 412 to 527 Å. Implications: Our paper presents original research in the field of characterization of solid material obtained by single-staged steam gasification of waste tires, which were produced and exploited in conditions of Russia. Modern technology allows thermal utilization of waste tires by obtaining powders of carbonaceous material, which could be used as fuel, adsorbent, etc., but this process usually consists of two stages – pyrolysis in inert medium and activation in steam or carbon dioxide. One of the most promising directions of technological development is simplifying this process into single step, ensuring that the obtained material could be used as carbon black or adsorbent for gas steam cleansing. No data on suitability of carbonaceous material obtained by single-step steam pyrolysis of all-season waste tires to be adsorbent and/or carbon black is present in the literature. In order to evaluate the suitability of the obtained material to be adsorbent, the high specific surface area should be determined, while CAS technical standards specify many chemical and physical properties of industrial carbon black. The aim of the current article is to study the properties of carbonaceous material obtained during single-staged steam gasification of four different all-season tires (due to their widespread application worldwide) and evaluate its fitness as industrial-scale carbon black or adsorbent. The additional problem addressed was the evaluation of the variation in characteristics of carbonaceous material obtained due to different origins of tires. Experiments were conducted in a tubular lab reactor in order to simplify the experimental procedure while ensuring the applicability of the obtained results to practical conditions. The obtained results could be used for the development of the technology for closed-cycle tire processing (because black carbon is used for tire production) and adsorbent production. The characteristics of the materials obtained allow us to choose optimal parameters for such treatment and develop special policies and programs, which will integrate and regulate waste tire utilization via steam gasification. [ABSTRACT FROM AUTHOR]

Nowadays sustainability is a key topic and waste should be considered a resource. For this reason, a large body of literature is being developed on the management of the large quantity of post-consumer tires with sustainable approaches. The ongoing research activity on tires is focused on providing eco-sustainable solutions aimed, on one hand, at reducing the amount of waste and, on the other hand, at optimizing and improving the technologies and methodologies to obtain 'green' products to be recycled on large scale. This review examines the solutions for the reuse of waste from post-consumer tires proposed in the literature during the last five years (2015–2019) with a focus on advantages, drawbacks and future research developments of each end-of-life tires (ELTs) recovery technology. The final aim is to provide a comparison of different fields of application for the recovery of post- consumer tires, particularly for those researchers who want to start an activity in this field. The results show that the most investigated field of application is the civil engineering area. However, it could be environmentally and socially useful to further investigate solutions suitable for recovery in sanitary applications such as water purification. Porous carbon, obtained from ELTs by pyrolysis and subsequent activation, can be successfully used as adsorbent to remove contaminants that could be harmful to the environment and human health. The latter application seems to be particularly advisable in less economically developed areas as it would represent a possible solution to the problem of environmental reclamation of water resources. [ABSTRACT FROM AUTHOR]

The cyclic utilization of waste tires has been a major problem that plagued the industry. In this paper, we explore a novel method of resource integration and application to solve this problem by using waste tires as the electrode materials. The waste tires were carbonized and coated with sucrose to prepare nano sulfur-carbon (NSC) and carbon-coated nano sulfur-carbon (NSC/C) materials. The results of the microstructures and morphologies showed that the NSC was composed of hexagonal ZnS nanoparticles and amorphous carbon. Electrochemical tests showed that the uncoated NSC composite had a high capacity of 426.6 mAh g-1, but it also presented a low initial efficiency with poor rate and cycling performance. After coating, the NSC/C exhibited an acceptable specific capacity of 374 mAh g-1 with lower capacity fading and superior cycling performance than NSC. Materials obtained from carbonized waste tires have great potential for use as anode materials in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Waste tires (WTs) are becoming a significant environmental, economic, and technological challenge due to their high contents of combustible composition and potential for valuable materials and energy resources. Few studies in developing and even developed countries have been carried out to assess the challenges regarding waste tire management and to suggest the best alternative solutions for managing this waste stream. Although developed countries made progress in waste tire management needs by implementing more efficient innovative recovery and recycling methods, and restrictive regulations regarding the management of used tires, in many developing countries, the management of waste tires has not received adequate interest, and the processing, treatment, and disposal of waste tire is still nascent. In recent years, worldwide, several methods for managing used tires, including other principal alternatives for managing end-of-life tires defined in the 4Rs: reduction, reuse, recovery, and recycling, have been adopted and applied to minimize serious threats to both the natural environment and humans. This paper attempted to establish stakeholders' action that has the responsibility in waste tire management in Botswana. This study also analyzed important aspects on waste tire management in Botswana. A synthesis of approaches was employed in the present investigation to determine the factors influencing effective performance of waste tire management practice in Botswana. Data for the present study were obtained using relevant published literature, scientific journals, other third-sector sources, academic sources, and research derived from governments and other agencies and field observations. Group discussions with the participants and semistructured interviews with professionals were carried out. The outcomes of this investigation are a wide-ranging outline concerning the participants that are important in waste tire management, and a set of aspects affecting the management of waste tires. The information provided by this study is very critical for reviewing and updating the methods and tools to update waste tire data and trends to improve waste tire management efficiency, suggesting innovative methods of recovering and recycling this waste stream in Botswana. Implications: Waste tire management in Botswana demonstrates challenges that epitomize many developing and transitioning countries due to inadequate knowledge to implement integrated programs that incorporate environmental sustainability, stockpiling of whole tires at landfills, lack of consistent and systemic approaches to tire regulation, lack of methods and tools to update tire data and trends, limited application of technology to process and treat WTs, and lack of societal acceptance. To improve WT management efficiency in Botswana, it is critical to implement efficient and well-functioning approaches, including the circular economy; encourage the harmonization of policies; implement recovery and recycling methods of waste tires; prohibit stockpiling of WTs at landfilling and unofficial dumpsites; and promote economic instruments such as the tax system and the extended producer responsibility. [ABSTRACT FROM AUTHOR]