Pyrolysis Of Scrap Tires Research Articles

Carbons prepared by microwave co-pyrolysis of waste scrap tyres and corn cob: Effect of cation size and charge on xylene adsorption

Carbons prepared by pyrolysis of waste corn cobs or scrap tyres using different microwave power (200, 400, 600 W) are compared with carbons prepared by co-pyrolysis of corn:tyre mixtures in various mass ratios without/with activator (KOH, ZnCl2, K2CO3, NaOH in solid or liquid phase). Activation and co-pyrolysis of corn:tyre mixture was proved to be advantageous, prepared activated carbons showed enhanced xylene adsorption compared to non-activated. Activated carbons prepared from corn:tyre mixture at mass ratio of 4:1 and using ZnCl2 in liquid and ZnCl2 and K2CO3 in solid phase showed the highest adsorption capacities (∼171, 139 and 104 mgxylene·g−1, respectively) despite the opposite trend in their microporosity. Molecular modeling proved a preferential interaction of xylene with activated carbons porous structure through Zn2+, K+ and Na+ ions. The smallest cation with the highest positive charge, Zn2+, interacts the most strongly with xylene. The strength of cation-xylene interaction decreases as follows: Zn2+ > Na+ > K+. As the strongest were proved xylene interactions with Pore (5.2 Å)_Zn2+ > Pore (8.5 Å)_Zn2+ > Surface_Zn2+ > Pore (5.2 Å)_Na+ ∼ Pore (5.2 Å)_K+, which explains the highest adsorption capacities of ZnCl2-activated carbons despite of their lower microporosity compared to carbon activated by using K2CO3(s).

Technoeconomic analysis: the potential and opportunities of transforming Saudi Arabian scrap tires into synthetic fuel via vacuum pyrolysis

Environmental hazards linked with scrap tires have been a great concern for the Saudi government. The Kingdom of Saudi Arabia has a Vision 2030 project with an aim to produce 50% of its energy through renewable energy resources. The tire market in the country reached 22.2 million units in 2022 and is expected to increase up to 24.9 million in 2028 with a growth rate of 2.11%. This study used a vacuum pyrolyzer for transforming scrap tires into tire-derived oil (TDO), along with other products such as synthesis gas (syngas) and carbon black. It provides a feasible way of transforming scrap tires into synthetic fuel via vacuum pyrolysis (a thermochemical approach). Vacuum pyrolysis of scrap tires at temperature 350–400oC yields 45%–55% derived oil, 10%–15% steel wires, 30%–35% carbon black, and 10%–15% non-condensable gases. The heating value of the obtained tire-derived oil is 32–37 MJ/kg, which is somehow less than that of diesel, which has an energy value of 44–46 MJ/kg. Such products are expected to be obtained after the successful adaptation of advanced techniques such as thermochemical approaches and can successfully be used as an alternative to fossil fuels. Based on the scrap tire produced in the country, if Saudi Arabia can process 22.2 million units of tires (trucks and passenger cars) annually through vacuum pyrolysis, it can earn approximately $47.40 million annually (or $2.14 per tire) through tire pyrolysis. Utilization of carbon black (recovered from scrap tire pyrolysis) in manufacturing tires can save approximately 2.5 tons of CO2 production compared to per ton production of new (virgin) carbon black. This study suggested pyrolysis to be a viable recycling and waste tire management technique, and it can be an independent profitable operation in Saudi Arabia and helps in meeting the Saudi Vision 2030.

Sustainable utilization of value-added products from the catalytic and non-catalytic pyrolysis of motor car scrap tire: Suitability of produced char for energy generation and sugar mill wastewater treatment

Clean fuel and sustainable energy utilization are essential requirements to address the impacts of global warming and climate change. In this study, the pyrolysis of motor car scrap tire was investigated in a fabricated cylindrical stainless steel reactor, operated at 450, 500, and 550 °C for 50 min with or without the addition of a catalyst. The catalytic condition yielded maximum char of 59% w/w obtained at 450 °C. The addition of the catalyst also enhanced oil yield up to 33% w/w at 500 °C while the maximum gas fraction of 44% w/w was obtained under the non-catalytic condition, at 550 °C. The TGA/DSC analysis showed that the pyrolysis char had a specific heat capacity (Cp) of 35 J/g.K, relating to its high thermal stability for applications in furnaces, reactors, and heat construction materials. The char, after chemical activation, with the XRD analysis, showed that the produced activated carbon (AC) has a good crystalline structure (with high interplanar distances). The BET analysis revealed that the AC has a high surface area of 1065 m2/g (average pore diameter of 3.36 nm) which enhanced the adsorption capacity of the AC to about 90 % efficiency for the removal of the heavy metal, cadmium, from sugar mill wastewater.

Boron, oxygen co-doped porous carbon derived from waste tires with enhanced hydrophilic interface as sustainably high-performance material for supercapacitors

The number of scrap tires has been increasing in recent years and pyrolytic carbon black (CBp) is an important product of scrap tire pyrolysis. However, due to the poor surface activity and the high contents of ash and carbonaceous deposits, the untreated CBp can only be used for low-end rubber products with poor economic efficiency. Herein, we propose a new Boron, Oxygen co-doped porous carbon (AB-CBp) through a facile KOH activation and boric acid modificating CBp. The modification of boron and oxygen heteroatoms has dramatically increased its specific surface area (SSA), hydrophilicity and conductivity, leading to the enhanced specific capacitance and rate performance. The assembled zinc-ion hybrid super-capacitor (ZIHC) devices have a maximum capacity of 83.2 mAh g−1 at 0.1 A g−1. Moreover, this device demonstrates an impressive cycling life with a high capacitance retention rate of 92.3 % at 10 A g−1 after 30,000 cycles. The work not only paves a new way for the efficient utilization of CBp from waste tires, but also demonstrates the employments of inexpensive and sustainable material for the further development of energy storage.

Microporous carbon prepared by microwave pyrolysis of scrap tyres and the effect of K+ in its structure on xylene adsorption

This work brings novel information about microwave-assisted pyrolysis of scrap tyres, the industrial realization of which is still an engineering challenge due to both missing fundamental processing issues as well as how to enhance the engineering quality of pyrolytic products, mainly of solid carbon black. One-step microwave pyrolysis of scrap tyres for 50 min at power of 440 W with KOH activation in the mass ratio of 1:3 (scrap tyres:KOH) is successfully applied for the first time to yield micropores-containing carbon black which application potential was verified for xylene adsorption from waste gas. Compared to conventional high-temperature pyrolysis, the microwave pyrolysis requires shorter time and thus significantly reduces input energy. Two-step microwave pyrolysis of scrap tyres at 440 W does not result in more organized graphene-based carbon, but turbostratic carbon is more perturbed. The higher microwave power of 950 W within one-step microwave pyrolysis does not enhance the graphitization of carbon black, but shorten the microwave pyrolysis time to 20 min. The two main physicochemical properties of the novel micro-macroporous carbon black determining its adsorption performance for xylene are the microporosity/large volume of micropores and K+ present in the carbon structure. Micropores <0.52 nm with/without K+ and cavities <0.82 nm with K+ within carbon structure are proved by molecular modeling to be the sites with the highest affinity for xylene adsorption. Higher adsorption capacity of activated carbon blacks compared to non-activated ones correlates with molecular modeling results. More perturbed carbon structure does not affect the xylene adsorption.

Characterization, performance assessment, techno-economic potential, and process optimization of scrap tire pyrolysis in Bangladesh

The objective of this study was to assess the effects of tire pyrolytic oil (TPO) blends on diesel engine performance, evaluate the techno-economic viability, and optimize the process variables using the response surface methodology (RSM) in order to increase the maximum product yield. To test engine performance and exhaust emission characteristics, the derived pyrolytic oil was employed in a four-stroke diesel engine with different diesel fuel blend ratios. It has been found that engine performance using a pyrolytic oil blend is much closer to the diesel fuel engine performance. This paper has briefly explored the economics of TPO production and the reliability improvements of the pyrolysis processes to make them viable for commercial applications. The techno-economic feasibility analysis has been conducted on a 10 tons'/day capacity pyrolytic plant. It has been found that the total cost and net revenue generation from one ton of scrap tires are $225.25 and $410.2, respectively. Additionally, the 8-year project's payback period is only 2.96 years, while the internal rate of return (IRR) was found to be 27.81%. The reduction in greenhouse gas (GHG) emissions was estimated at 1,658.62 tons per year. The RSM was used to optimize the process parameters for maximizing product yield. At the ideal conditions of 464.11 °C operating temperature, 59.53 min of running time, and 1.63 cm particle size, the projected maximum pyrolytic oil yield of 87.31 wt% and char yield of 7.63 wt % was reached. The reliability and applicability of the process were ensured through the developed regression model for pyrolytic oil and char with a high F-value and low P-value. The predicted results were validated, and it was found that the experimental data varied only by 1.21% from the predicted values. Therefore, this study provides investors with scientific guidance for pyrolysis-based energy generation projects in Bangladesh that are financially viable.

Production of transportation fuels via hydrotreating of scrap tires pyrolysis oil

The hydrotreating of scrap tires pyrolysis oil over commercial Ni-Mo/Al2O3 catalyst was researched for the best processing scheme allowing the production of high-quality alternative transportation fuels components of gasoline, jet, diesel, and marine fuel. Despite the initial high content of olefins, aromatics, sulfur, and nitrogen in pyrolysis oil, fuel components obtained by redistillation after the hydrotreating at 360 °C and 10 MPa met the majority of standard fuel specifications. Although the octane number of the naphtha fraction was lower, this fraction can be used as acomponent of the gasoline pool directly or after the catalytic reforming. Kerosene fraction can be utilized as jet fuel after the additional mild hydrotreatment or blending with hydroprocessed esters and fatty acids (HEFA) to decrease aromatics content. Diesel fraction can be blended with hydrotreated vegetable oils (HVO) to fulfill the density and cetane index specification. The bottom residue can be utilized as a low-sulfur fuel oil component in marine transportation.

An economic analysis of scrap tire pyrolysis, potential and new opportunities

Scrap tire recycling is a concern for local and national governments because of the associated environmental hazards. As motor vehicle use increases around the globe, fueled by booming demand in the emerging market, more governments are imposing stringent recycling rules for scrap tires. New and emerging technologies have been introduced to solve the recycling problem. Pyrolysis, which involves the decomposition of materials at elevated temperatures under inert conditions, converts scrap tires into gas and liquid fuels and these products can be used by other industries such as chemical, energy and transportation industries. The feasibility of pyrolysis depends on several factors, including the material content of the scrap tire and market value of the products. Current and past market conditions suggest that pyrolysis plants can be run profitably as independent operations. This study evaluated the economic potential of the pyrolysis industry based on evolving market conditions and forecasts the potential market size based on the volume of scrap tires expected to come into the market in the next 20 years. Separate models were used for market predictions for Europe and Turkey. The economic benefits of using scrap tire pyrolysis were discussed, including the potential monetary value of adopting such policies for Turkey.

Pyrolysis as an alternate to open burning of crop residue and scrap tires: Greenhouse emissions assessment and mechanical performance investigation in concrete

In this study, waste from agriculture and industrial sources was transformed into valuable biochar to reduce the environmental threats associated with the open burning of this waste and used as an additive in concrete for the first time to impart superior mechanical characteristics to conventional concrete. Carbonaceous inert particles were derived from the pyrolysis of wheat straw, cotton stalk, and scrap tires. The environmental impact assessment was carried out to gauge the impact of pyrolysis process on char production and the global warming potential for engineered concrete. Based on the analysis, pyrolysis of scrap tires manifested the lowest net global warming potential of −1.285 KgCO 2 -eq. Furthermore, the characterization of synthesized inert particles was carried out by using Laser granulometry, scanning electron microscopy, x-ray diffraction analysis, thermo-gravimetric analysis, and Raman spectroscopy. Thereafter, the mechanical performance of concrete incorporated with synthesized inert particles by 1% of cement weight was evaluated and compared with the reference formulation of concrete having no amount of synthesized inert particles. A significant improvement of 51.42% in terms of flexural resistance was achieved by using pyrolyzed cotton stalk. Fracture toughness index and fracture energy were also improved with the inclusion of these inert particles. To rationalize the improved performance of specimens engineered with synthesized inert particles, fracture path analysis was conducted. In comparison to the reference formulation, composites reinforced with pyrolyzed scrap tires rendered maximum improvement in compressive strength by 43.1%. From the analysis of the emissions to strength ratio of concrete, specimens containing pyrolyzed scrap tires ensued the maximum reduction of 31.31% relative to the reference formulation. • Agricultural residue and scrap tires waste were transfigured to biochar through pyrolysis. • Net negative global warming potential was attained by opting for pyrolysis. • Maximum gain of 51.4% in flexural resistance was obtained with pyrolyzed cotton stalk. • Concrete with 43.1% enhanced compressive strength was made with pyrolyzed scrap tires. • 45.58% increase in strength to emissions ratio was achieved with the addition of pyrolyzed scrap tires.

Optimization of Operating Parameters for Tyre Pyrolysis Oil Blended Single Cylinder Diesel Engine

Abstract: Increasing industrialization and motorization led to a significant rise in demand for petroleum products. As these are the non renewable resources, it is difficult to predict the availability of these resources in the future resulting in uncertainty in its supply and price and impacting growing economies like India, importing 80% of the total demand of the petroleum products. Many attempts have been made by different researchers to find out alternate fuels for Internal Combustion engines. Many alternate fuels like Biodiesel, LPG (Liquefied Petroleum Gas), CNG (Compressed Natural Gas) and Alcohols are being used nowadays by different vehicles. In this context pyrolysis of scrap tyres can be used effectively to produce oil, thereby solving the problem of waste tyre disposal. In the present study Experimental investigations were carried out to evaluate the performance and emission characteristics of a single cylinder diesel engine fuelled by TPO10, TPO15, and TPO20 keeping the blend quality by controlling density and viscosity of tyre pyrolysis oil within permissible limit of euro IV diesel requirement to study its replace ability. The investigation involves three parameters such as blend proportion, injection timing and injection pressure, a simultaneous optimization method called Taguchi was used in this work. This method requires fewer numbers of trials for fixing optimum levels. As per this method nine experiments were required to be conducted and the results were used for optimization. This is the primary advantage as well as disadvantage of this method. In order to eliminate this difficulty and improve the quality of the research work, twenty-seven experiments were conducted in this work and the results were used for optimization. In addition, an ANOVA was also performed for the parameters to evaluate its percentage contribution over the desired output. Using the optimum levels, a full range experiment was conducted to compare its performance and emission behaviour with standard diesel operation. Keywords: Operating parameters, Diesel Engine, Tyre Pyrolysis Oil (TPO), Performance, Emission

Microwave heating mechanism and Self-healing performance of scrap tire pyrolysis carbon black modified bitumen

Conventional asphalt mixture has poor microwave absorbing performance and microwave heating efficiency. Based on the characteristics of dielectric loss of scrap tire pyrolysis carbon black (PCB), it is proposed to improve the microwave absorbing performance and self-healing rate of bitumen. The phase composition and electromagnetic parameters of PCB were tested to reveal its microwave heating mechanism. The preparation parameters, heating characteristics and self-healing properties of PCB modified bitumen were studied through the dispersion uniformity test, microwave heating test and SCB test. The main phases of PCB are microwave absorbing carbon and silicon, indicating that PCB is a good electric loss microwave absorbing material. 40 min is the recommended mixing time of 15% PCB modified bitumen. PCB's dosage, microwave frequency and microwave heating time have significant effects on the microwave heating characteristics of PCB modified bitumen. PCB can improve high-temperature stability, thermal conductance, heat storage capacity and self-healing rate of bitumen.

The improved diesel-like fuel from upgraded tire pyrolytic oil

Tire pyrolytic oil (TPO) obtained from thermal pyrolysis of scrap tires is not a diesel equivalent fuel which can be used directly in vehicles due to its high density, viscosity, sulfur content, low flash point and low cetane index. It can only be used in a limited way by mixing with diesel fuel (DF) in amounts less than 30 %. In this study, the pyrolysis of scrap tires was carried out at a heating rates of 5 and 10?C min-1 in the range of 450?600?C, using a mixture of hierarchical zeolite (HZSM-5), mesoporous silica (MCM-41) and quicklime (CaO) as the catalyst. The obtained TPO and catalytic pyrolytic oil (CPO) were upgraded by pre-treatment, and distillation consisting of a mixture of Cu(I)-loaded mesoporous aluminosilicate (Cu(I)?MAS) and MCM-41, desulfurization and decolourization steps, respectively. To obtain diesel-like fuel, the upgraded catalytic pyrolytic oil (UCPO) and biodiesel (PBD) obtained from palm oil were blended in certain proportions. Density, viscosity, flash point and cetane index of the obtained diesel-like fuels were found within the limit values of diesel fuel.

Investigation on the Potential Production of Diesel from Waste Tires

An alternative fuel production was performed by catalytic-pyrolysis of waste tires under a nitrogen (N2) environment and with a zeolite catalyst. Pyrolysis of scrap tires has been pointed out as an alternative to the incorrect disposal of tire wastes. Pyrolysis processes can produce tire-derived oils that may be used as fuel or added to conventional fuels, producing fuel blends with improved properties and reduced cost. The pyrolysis process can contribute to removing tire residues from inadequate sites and it can be a sustainable process to produce alternative fuels. The project investigated the conversion of the waste tires into diesel as one way of waste management and also as a viable process which in turn helps to meet the fuel demand. Uses of the diesel and the by-products from the process were also outlined. Experiments were conducted on the pyrolysis process in order to find the optimum conditions for producing the diesel through pyrolysis; the temperature and residence time were optimized in order to get maximum output from the process. The optimum temperature of the reaction was found to be 520?C and the optimum residence time was 92.5 minutes. Quality tests of the product were then conducted on the obtained product and most of the properties were found to meet the required standard specifications. The most critical properties which are density, final boiling point, flash point and kinematic viscosity, were found to be 0.8495 g/cm3, 370?C, 50.5?C and 3.681 cSt, respectively, and they were within the required specifications. Quality analysis showed that a quality product that is suitable for automobiles could be obtained from the process. The process also produces useful by-products such as char, which can aid in the purification process of the diesel after conversion to activated carbon. The process is environmentally friendly if the appropriate pollution prevention methods like gas absorption are thoroughly implemented. Waste tires are an alternative source of diesel and hence the feasibility of implementing the project on a large scale.

Production of Transportation Fuels Via Hydrotreating of Scrap Tires Pyrolysis Oil

Production of Transportation Fuels Via Hydrotreating of Scrap Tires Pyrolysis Oil

Composite asphalt binder modification with waste Non-tire automotive rubber and pyrolytic oil

Ethylene-propylene-diene monomer (EPDM) rubber is a synthetic rubber having a share of about one-half of the total consumption of non-tire automotive rubber parts such as weather strips, window seals, hoses, etc. Pyrolysis is gaining attention as a thermochemical route for the effective and sustainable treatment of end-of-life tires. Tire pyrolytic oil (TPO) is one of the principal products generated from the pyrolysis of scrap tires. This study evaluated the use of TPO and EPDM waste rubber in composite asphalt binder modification through rheological characterization. In addition, the study also compared two processes (with and without pre-treatment/premixing of TPO and EPDM) for the preparation of the composite modified asphalt binders. The high temperature rheological characterization of binders was executed by the Superpave rutting criterion, failure temperatures, and multiple stress creep and recovery (MSCR) test. Frequency sweeps were conducted at multiple temperatures to study the changes in complex modulus and phase angle master curves. Also, the frequency sweep data was employed for analyzing the viscoelastic behavior of binders through storage and loss moduli crossover response. Furthermore, rheological tests including Superpave fatigue parameter, linear amplitude sweep (LAS), and binder yield energy test (BYET) were conducted at intermediate temperatures on the long-term aged binders. The observed results suggested an improvement in the asphalt binder performance with the composite modification in comparison to the single modification with EPDM and TPO alone. Pre-mixing of TPO and EPDM before adding to asphalt binder proved to be a better approach for preparing composite modified binder with EPDM rubber and TPO, and yielded better high- and intermediate-temperature performance.

Detailed nature of tire pyrolysis oil blended with light cycle oil and its hydroprocessed products using a NiW/HY catalyst

The pyrolysis of scrap tires is a very attractive strategy to valorize chemically these end-of-life wastes. The products of this step and any additional one, such as hydrotreating, are relatively complex in nature entangling the understanding and limiting the viability. In this work, we have investigated in detail the composition of a tire pyrolysis oil blended with light cycle oil (from a refinery) and its hydrotreated products using a bifunctional NiW/HY catalyst at 320–400 °C. We have applied a set of analytical techniques to assess the composition, namely simulated distillation, ICP, GC/FID-PFPD, GC × GC/MS, and APPI FT-ICR/MS. Our results show the strength of our analytical workflow to highlight the compositional similarities of this pyrolysis oil with the standard refinery streams. The main differences arise from the higher boiling point species (originated during the pyrolysis of tires) and relatively high concentration of oxygenates. These effects can be minimized by hydrotreating the feed which effectively removes heteroatomic compounds from the feed while boosting the quantity and quality of gasoline and diesel fractions.

Thermogravimetric Kinetics Study of Scrap Tires Pyrolysis Using Silica Embedded With NiO and/or MgO Nanocatalysts

Abstract In this study, a set of three new silica-based embedded with NiO and/or MgO nanocatalysts (SBNs) have been prepared and tested for the pyrolysis of scrap tires (STs). The intent is to identify and optimize the best nanocatalyst that decreases the operating temperature and speeds up the pyrolysis reaction rate. The influence of the three prepared SBNs nanocatalysts on STs was scrutinized using thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). The kinetic triplets were estimated utilizing the isoconversional method of the Ozawa–Flynn–Wall (OFW) corrected model. Experimental TGA and FT-IR results showed a thermal decomposition of all volatile organic additives alongside the polyvinyl compounds at a lower temperature in the presence of these SBNs. However, a competitive decomposition behavior appeared for each SBN nanocatalysts. The kinetic triplets’ findings showed different effective activation energy trends at two different conversion regions (low and high conversions), suggesting different reaction mechanisms confirmed by the reaction kinetic models. Interestingly, NiO-MgO-SBNs showed the highest reaction rate for this thermo-pyrolysis of STs, which could be because of synergetic interaction between NiO and MgO nanoparticles. Moreover, the results of the change in Gibbs free energy of activation (ΔG‡) indicated the promising catalytic activity for those SBNs by promoting the spontaneity of pyrolysis reaction. These proof-of-concept findings could promote the futuristic use of NiO-MgO-SBNs at the industrial level toward sustainable ST pyrolysis.

Pyrolysis of scrap tire by utilizing zeolite as catalyst

Pyrolysis of waste tyres has been taken along 2 stage bed reactor. Waste tyres has been 1rst pyrolysis under perfect bed reactor, letter included pyrolysis gases has been forwarded by secondary catalytic reactor involved along 2 kinds of zeolite catalysts, which has been ultras table HY type & ZSM-5 catalyst. The Temperature of catalytic has been calculated regards observing issues on yield of products through waste tyres pyrolysis catalyst. Under this paper outputs shows that along enhance temperature of catalytic yield of gas enhanced at increase of yield of oil. It was describing that there was dramatic enhancement under concentration regards single ring aromatic compounds under fraction regards catalysis of derived oils. A un-catalyst tire pyrolysis was carried out under this paper, under order to correlate the pyrolysis of idle tires along the HY Impetus & ZSM-5 Impetus. The pyrolysis temperature was changed through 450 to 600 OC the impulses were replaced along similarly sized Such like ignorance reached counts under fraction of light around 11.63 wt%, o-xylen 4.40 wt%, benzene 1.7 wt% & m/p-xylen 12.3 wt% along HY catalyst, at temperature of pyrolysis, temperature of catalysis & ration of catalyst tyre around 400, 500 & 0.5, Under which light fraction is around 70.8 wt% under derived oil. Waste tires Synergist pyrolysis uses catalyst of zeolite HY & ZSM-5 which was observed related to effect regards temperature of reactant under yield items. Results show that effect of ZSM5 & catalyst zeolite HY has been to prove diminish yield regards oil along confirming enhancement under yield of gas.

Production and characterization of diesel-like fuel by catalytic upgrading of scrap tire pyrolysis oil using basic catalyst derived from blood cockle shell (Anadara Granosa)

This paper investigates the catalytic upgrading process in overcoming the scrap tire pyrolysis oil (STPO) complexities using a calcium-based catalyst derived from blood cockle shell (Anadara granosa). The calcined blood cockle (CBC) shells were synthesized by varying the temperature of calcination to 800, 900 and 1000 °C. In order to investigate the physico-chemical properties, the STPO was subjected to test method according to ASTM D975. The final distilled oil obtained from catalytic upgrading underwent gas chromatography with mass spectroscopy (GC–MS) analysis, in order to identify its chemical composition. According to the results, CaO material gives the lowest sulphur content (0.08%), compared to Ca(OH)2 and Na2CO3 catalysts. Among the CBC materials, the highest distilled oil yield is the CBC-1000 catalyst, with a value of 37.7%. The GC–MS analysis of distilled oil obtained from catalytic upgrading using the CBC-1000 catalyst reveals that, predominantly, the hydrocarbon chain is between C8 to C10, which is similar to conventional diesel fuel. The results also infer that there is improvement in STPO in terms of sulphur content (%), yield, and chemical compositions via the catalytic upgrading process. In conclusion, the CBC catalyst derived from blood cockle shell revealed that it has potential in upgrading the STPO to diesel-like fuel.

Study of scrap tires pyrolysis – Products distribution and mechanism

Pyrolysis process is one of the potential technologies to convert scrap tires (STs) into high-value resources. Though many studies have been conducted, understanding of products characteristics and pyrolysis mechanism is still far from satisfactory to its application. This paper aims to give an in-depth view of STs pyrolysis, providing a uniform products distribution pattern, a fundamental comprehension of the mechanism. Herein, TG – FTIR/MS and Py – GC – TOF/MS were used to investigate the STs pyrolysis, thermal cracking features and pyrolysis paths. The process of STs decomposition contained three interacted parts, with four kinds of products in total, including gaseous, aliphatic hydrocarbons, aromatic hydrocarbons and some other kinds of compounds. Among aromatic hydrocarbons, ethylbenzene, paraxylenes, and mesitylenes were the components with higher content. d -limonene was the dominant composition of aliphatic hydrocarbons. Alkenes and cycloalkenes were initially formed during the pyrolysis process. Then, hydrogenation, substitution and cyclization reactions occurred afterwards. Finally, benzene, benzene derivatives and condensed benzene were generated after complex free radical reaction process. The research provides further insight into the products characteristics and mechanism of STs pyrolysis, which gives a theoretical basis for pyrolysis application of STs and other polymers mixture into high-value products. • Scrap tires pyrolysis process consists of three interacted parts of diverse rubbers. • Scrap tires pyrolysis products mainly concentrate in aromatic hydrocarbons. • Contents of aliphatic, aromatic hydrocarbons vary with temperature and reaction time. • Principle of scrap tires pyrolysis is dominated by free radical reaction mechanism.