Near-Infrared Spectroscopy as a Tool for Simultaneous Determination of Diesel Fuel Improvers.

Diesel and biodiesel blends requires additives to improve fuel quality properties and engine performance. Diesel improvers are added before, during and/or after the fuel is blended. However, no accurate rapid and non-destructive analytical method is used during the fuel production that could determine the exact concentration of various types of improvers in diesel fuel. Thus, the aim of this study was to determine the concentration of several improvers in diesel matrices at the same time. Three types of diesel improvers, i.e., a cold-flow improver (CFI), a conductivity-lubricity improver (CLI), and a cetane number improver (CNI), were simultaneously determined by near-infrared (NIR) spectroscopy combined with multivariate statistical analysis and the partial least squares algorithm. The prediction models yielded high correlation coefficients (R 2) >0.99 and satisfactory values of the root mean square error of calibration as follows: CLI 4.2 (mg·kg-1), CFI 4.6 (mg·kg-1), and CNI 5.3 (mg·kg-1). The residual standard deviation of the repeatability was calculated to be around 8%. These results highlight the potential of NIR spectroscopy for use as a fast, low-cost, and efficient tool to determine the concentrations of diesel improvers. Moreover, this technique is suitable for application during refinery production, especially for the purpose of online monitoring to prevent overdoses of additives and save financial expenses.

Direct Polypropylene and Polyethylene Liquefaction in CO2 and N2 Atmospheres Using MgO Light and CaO as Catalysts.

The polyolefin to lighter molecules reaction reduces the waste-plastic residues to produce fuels and valuable chemicals. Commercial MgO light and CaO were used as catalysts for the direct polyethylene and polypropylene liquefaction in N2 or CO2 atmospheres. The products were analyzed (ATR-FTIR, GC-FID/TCD, GC-FID, density, refractive index). The use of MgO light and CaO improved the conversion of propylene and ethylene to liquid products. In addition, low gaseous and solid products yields were obtained. A good production of organic liquids in the gasoline, diesel and kerosene boiling range was obtained. The use of CO2, in some cases, led to a higher conversion into liquids compared with the reactions performed in the N2 atmosphere. In addition, the use of the CO2 atmosphere led to a higher content of products with a boiling range in the diesel and kerosene ranges.

Phonolite Material as Catalyst Support for the Hydrotreatment of Gas Oil and Vegetable Oil Type Feedstocks.

Phonolite material has shown to be promising catalyst support for the deoxygenation of triglycerides. In this work, we continue with our previous research by synthesising and testing three acid-treated phonolite-supported Co-Mo, Ni-Mo and Ni-W catalysts for the hydrotreating of atmospheric gas oil and co-processing with rapeseed oil at industrial operating conditions (350-370 °C, WHSV 1-2 h-1, 5.5 MPa) in the continuous regime for more than 270 h. The phonolite-supported catalysts showed hydrotreating activity comparable with commercial catalysts, together with a complete conversion of triglycerides into n-alkanes. During co-processing, the Ni-promoted catalyst showed strong stability, with similar activity previous to the rapeseed oil addition. Our results enable us to evaluate the suitability of phonolite as catalyst support for the development of plausible alternatives to conventional hydrotreating catalysts for the co-processing of middle distillates with vegetable oils.

Hydrocracking of Heavy Fischer-Tropsch Wax Distillation Residues and Its Blends with Vacuum Gas Oil Using Phonolite-Based Catalysts.

The Fischer-Tropsch heavy fraction is a potential feedstock for transport-fuels production through co-processing with fossil fuel fraction. However, there is still the need of developing new and green catalytic materials able to process this feedstock into valuable outputs. The present work studies the co-hydrocracking of the Fisher-Tropsch heavy fraction (FT-res.) with vacuum gas oil (VGO) at different ratios (FT-res. 9:1 VGO, FT-res. 7:3 VGO, and FT-res. 5:5 VGO) using phonolite-based catalysts (5Ni10W/Ph, 5Ni10Mo/Ph, and 5Co10Mo/Ph), paying attention to the overall conversion, yield, and selectivity of the products and properties. The co-processing experiments were carried out in an autoclave reactor at 450 °C, under 50 bars for 1 and 2 h. The phonolite-based catalysts were active in the hydrocracking of FT-res.:VGO mixtures, presenting different yields to gasoline, diesel, and jet fuel fractions, depending on the time of reaction and type of catalyst. Our results enable us to define the most suitable metal transition composition for the phonolite-based support as a hydrocracking catalyst.

Oxalic Acid as a Hydrogen Donor for the Hydrodesulfurization of Gas Oil and Deoxygenation of Rapeseed Oil Using Phonolite-Based Catalysts.

The use of renewable local raw materials to produce fuels is an important step toward optimal environmentally friendly energy consumption. In addition, the use of these sources together with fossil fuels paves the way to an easier transition from fossil to renewable fuels. The use of simple organic acids as hydrogen donors is another alternative way to produce fuel. The present work reports the use of oxalic acid as a hydrogen donor for the catalytic hydrodesulfurization of atmospheric gas oil and the deoxygenation of rapeseed oil at 350 °C. For this process, one commercial NiW/SiO2-Al2O3 solid and two NiW/modified phonolite catalysts were used, namely Ni (5%) W (10%)/phonolite treated with HCl, and Ni (5%) W (10%)/phonolite treated with oxalic acid. The fresh phonolite catalysts were characterized by Hg porosimetry and N2 physisorption, ammonia temperature programmed desorption (NH3-TPD), X-ray diffraction (XRD), and X-ray fluorescence (XRF). The sulfided metal phonolite catalysts were characterized by XRD and XRF. Hydrodesulfurization led to a decrease in sulfur content from 1 to 0.5 wt% for the phonolite catalysts and to 0.8 wt% when the commercial catalyst was used. Deoxygenation led to the production of 15 and 65 wt% paraffin for phonolite and commercial solids, respectively. The results demonstrate the potential of using oxalic acid as a hydrogen donor in hydrotreating reactions.

Synthesis and biological activity of new derivatives with the preserved carane system.

Terpenoid derivatives, which contain a preserved carane system in their structure, exhibit a broad spectrum of biological activities. Among them, we can distinguish insecticides, structures with pharmacological application etc. In the presented paper, the substrate - (-)-cis-caran-trans-4-ol was transformed using the reactions of typical organic synthesis to obtain novel derivatives. Most importantly, bromolactone ((-)-(1R,4R,6S)-2'-(bromomethyl)-4,7,7-trimethylspiro[bicyclo[4.1.0]heptan-3,3'-furan]-5'(4'H)-one) with the preserved carane system was synthesized. This bromolactone was tested for antifeedant activity against the lesser mealworm, Alphitobius diaperinus Panzer, and peach potato aphid (Myzus persicae). In addition, its moderate antibacterial activity was observed against the Bacillus subtilis strain (with Minimal Inhibitory Concentration of 200 µg/mL).