Gasoline like fuel from plastic waste pyrolysis and hydrotreatment

Recycling of plastic waste is desirable to lower environmental pollution and fulfil the requirements of circular economy. Energetic utilization is another possibility, however, municipal solid waste containing plastics is usually combusted to generate heat and electricity. An attractive way of dealing with plastic waste is pyrolysis, which has the potential of producing liquid hydrocarbons suitable as a transportation fuel. The pyrolysis results of three plastics produced in the largest amount globally, namely polyethylene, polypropylene and polystyrene as well as their mixtures are presented. The experiments were performed in a laboratory scale batch reactor. The pyrolysis oils were further processed by distillation to provide gasoline and diesel like (distillation cuts at 210 and 350 °C) hydrocarbons. The gasoline fractions were analysed by GC-MS and the composition was compared with the EU gasoline standard. It was found that the oils from PE, PP and PS contain compounds present in standard gasoline. Mixing PS with PE and PP before the pyrolysis, or the oils afterward produces much closer results to standard requirements as PS pyrolysis generates mostly aromatic content. As standard maximizes the olefin content of gasoline to 18 Vol%, hydrogenation was also performed using Pd based catalyst. The hydrogenation process significantly reduced the number of double bonds resulting in low olefin content. Results show that the pyrolysis of plastic waste mixtures containing PE, PP and PS is a viable method to produce pyrolysis oil suitable for gasoline-like fuel extraction and further hydrogenation of the product can provide gasoline fuels with low olefin content.

Reduced ice number concentrations in contrails from low-aromatic biofuel blends

Sustainable aviation fuels can reduce contrail ice numbers and radiative forcing by contrail cirrus. We measured apparent ice emission indices for fuels with varying aromatic content at altitude ranges of 9.1–9.8 and 11.4–11.6 km. Measurement data were collected during the ECLIF II/NDMAX flight experiment in January 2018. The fuels varied in both aromatic quantity and type. Between a sustainable aviation fuel blend and a reference fuel Jet A-1, a maximum reduction in apparent ice emission indices of 40 % was found. We show vertical ice number and extinction distributions for three different fuels and calculate representative contrail optical depths. Optical depths of contrails (0.5–3 min in age) were reduced by 40 % to 52 % for a sustainable aviation fuel compared to the reference fuel. Our measurements suggest that sustainable aviation fuels result in reduced ice particle numbers, extinction coefficients, optical depth and climate impact from contrails.

Comparison of Empirical Models to Predict Viscosity of Secondary Vacuum Gas Oils

This work presents characterization data and viscosity of 34 secondary vacuum gas oils (H-Oil gas oils, visbreaker gas oils, and fluid catalytic cracking slurry oils) with aromatic content reaching up to 100 wt.%. Inter-criteria analysis was employed to define the secondary VGO characteristic parameters which have an effect on viscosity. Seven published empirical models to predict viscosity of the secondary vacuum gas oils were examined for their prediction ability. The empirical model of Aboul-Seud and Moharam was found to have the lowest error of prediction. A modification of Aboul-Seoud and Moharam model by separating the power terms accounting for the effects of specific gravity and average boiling point improves the accuracy of viscosity prediction. It was discovered that the relation of slope of viscosity decrease with temperature enhancement for the secondary vacuum gas oil is not a constant. This slope increases with the average boiling point and the specific gravity augmentation, a fact that has not been discussed before.

Reduced ice number concentrations in contrails from low aromatic biofuel blends

Sustainable aviation fuels can reduce contrail ice numbers and radiative forcing by contrail cirrus. We measured apparent ice emission indices for fuels with varying aromatic content at altitude ranges of 9.1–9.8 km and 11.4–11.6 km. Measurement data were collected during the ECLIF II/NDMAX flight experiment in January 2018. The fuels varied in both aromatic quantity and type. Between a sustainable aviation fuel blend and a reference fuel Jet A-1, a maximum reduction in apparent ice emission indices of 40 % was found. We show vertical ice number and extinction distributions for three different fuels and calculate representative contrail optical depths. Optical depths of contrails (0.5–3 minutes in age) were reduced by 40 to 52 % for a sustainable aviation fuel compared to the reference fuel. Our measurements suggest that sustainable aviation fuels result in reduced ice particle numbers, extinction coefficients, optical depth and climate impact from contrails.

Determination of Essential Oil Composition of Naturally Growing Heracleum platytaenium L. Plant in Bolu Ecological Conditions

Heracleum platytaenium Boiss. (Öğrekotu) is a plant depend on the Apiaceae family, with intense aromatic content and known for its use in traditional medicine. This plant, which is one of the endemic plants of Turkey, is perennial and monocarpic. In this study, the essential oil of the Heracleum platytaenium Boiss., which grows naturally in the northern parts of Bolu province, was obtained by the hidro-distillation method in the Clevenger device and the essential oil components were investigated in the GC-MS device. As a result of the study, the essential oil ratio was determined as 1.4%. Octyl hexanoate (8.76%), 5-Octen-1-ol (7.04%), n-Octyl Caprylate (5.42%), and Beta-Eudesmol (5.01%) were determined as the main components. In this study, a total of 36 components (81.69%) were detected in the GC-MS device.