Rejuvenator Obtained by Pyrolysis of Waste Tires for Use in Asphalt Mixtures with Added Reclaimed Asphalt

Although in recent years, big progress has been made in the field of recovering waste tires, they still represent an unwanted waste and their production is constantly increasing. We can use waste tires as a raw material for a new product. In our study, multiple liquid products were produced by pyrolysis of waste tires. After extensive testing of their properties, we selected the most suitable pyrolytic product for the purpose of rejuvenation. Rejuvenators are designed to soften the old, brittle and stiff aged bitumen in reclaimed asphalt. Bitumen with its viscoelastic characteristics is the most important component of asphalt and dictates its behaviour. Commonly bitumen, after adding rejuvenator, becomes less viscous, more ductile and its coating properties are restored. By using a pyrolytic rejuvenator, the proportion of reclaimed asphalt added to the asphalt mixture was increased. The reuse of reclaimed asphalt and waste tires means a reduction in waste material and is therefore important for the preservation of the environment and sustainable development.

Single-Use Disposable Waste Upcycling via Thermochemical Conversion Pathway

Herein, the pyrolysis of two types of single-use disposable waste (single-use food containers and corrugated fiberboard) was investigated as an approach to cleanly dispose of municipal solid waste, including plastic waste. For the pyrolysis of single-use food containers or corrugated fiberboard, an increase in temperature tended to increase the yield of pyrolytic gas (i.e., non-condensable gases) and decrease the yield of pyrolytic liquid (i.e., a mixture of condensable compounds) and solid residue. The single-use food container-derived pyrolytic product was largely composed of hydrocarbons with a wide range of carbon numbers from C1 to C32, while the corrugated fiberboard-derived pyrolytic product was composed of a variety of chemical groups such as phenolic compounds, polycyclic aromatic compounds, and oxygenates involving alcohols, acids, aldehydes, ketones, acetates, and esters. Changes in the pyrolysis temperature from 500 °C to 900 °C had no significant effect on the selectivity toward each chemical group found in the pyrolytic liquid derived from either the single-use food containers or corrugated fiberboard. The co-pyrolysis of the single-use food containers and corrugated fiberboard led to 6 times higher hydrogen (H2) selectivity than the pyrolysis of the single-use food containers only. Furthermore, the co-pyrolysis did not form phenolic compounds or polycyclic aromatic compounds that are hazardous environmental pollutants (0% selectivity), indicating that the co-pyrolysis process is an eco-friendly method to treat single-use disposable waste.

Naphthalene and Alkyl Naphthalene from Catalytic Fast Pyrolysis of Biomass Over ZSM-5 Aggregates

Seed-induced synthesis of ZSM-5 aggregates was carried out without organic templates. The prepared ZSM-5 aggregates were used upgrading polar sawdust-derived pyrolytic vapors for the selective production of naphthalene and alkyl naphthalene. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments were conducted to analyze the pyrolytic product distribution and evaluate the catalyst performance. Due to the mesopores and proper acidities of ZSM-5 aggregates, the yield of naphthalene and methylnaphthalene over ZSM-5 aggregates were 36.0 and 123.7 mg/g, which were 2.7 and 2.6 times of those respectively over the commercial ZSM-5. The total selectivities of naphthalene and alkyl naphthalene could reach 61.56%.

Analytical Fast Pyrolysis of Glucose, Cellubiose and Cellulose: Comparison of the Pyrolytic Product Distribution

Analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was employed for the fast pyrolysis of glucose, cellubiose and cellulose in this study. The pyrolytic products from the three glucose-based materials were determined and compared to reveal the distribution differences. The results indicated that fast pyrolysis of the three materials obtained similar pyrolytic products, including the anhydrosugars, furans, linear carbonyls and cyclopentanones, but the distribution of the pyrolytic products differed from each other. The cellulose formed more anhydrosugars, but less carbonyls and furans than the glucose and cellubiose. The glycosidic bond of the cellubiose and cellulose would favor the pyrolytic depolymerization reactions to form various anhydrosugars, while inhibit the pyrolytic fragmentation reactions to produce linear carbonyls.