Hexadecane hydrocracking for production of jet fuels from renewable diesel over proton and metal modified H-Beta zeolites

Production of Sustainable Aviation Fuel by Hydrocracking of n-Heptadecane Using Pt-Supported Y-Zeolite-Al2O3 Composite Catalysts

Hydrocracking of fat or Fischer-Tropsch (FT) wax from biomass to produce the jet fuel of sustainable aviation fuel has been one of the key reactions. n-Heptadecane, which is one of the model diesel fractions produced from fat or FT wax, has hardly been used for hydrocracking of hydrocarbon for jet fuel production, while n-hexadecane has often been used as one of the model compounds for this reaction. In the present study, a HY-zeolite (50 wt %, SiO2/Al2O3 = 100)-Al2O3 (50 wt %) composite-supported Pt (0.5 wt %) catalyst [0.5Pt/Y(100)35A] was tested for hydrocracking of n-heptadecane using a fixed-bed flow reactor at a H2 pressure of 0.5 MPa, H2 flow rate of 300 mL/min, WHSV of 2.3 h-1, and a catalyst weight of 2 g. Fine-tuning of the temperature to 295 °C achieved the highest selectivity of 74% for the jet fuel fraction C8-C15 with the high conversion of 99%. The jet fuel yield reached 73%, which was almost an ideal maximum yield of 75%. Similar hydrocracking of n-hexadecane has just reported the maximum yield of 51% for jet fuel fraction. Further, 0.5Pt/Z(110)35A, which has a composition similar to that of 0.5Pt/Y(100)35A except for the type of zeolite, could not give as high yield of jet fuel as 0.5Pt/Y(100)35A because the rapid conversion to lighter fractions than the jet fuel occurred by the slight increase in the reaction temperature even at a lower temperature range.

Hydrocracking of crude palm oil to a biofuel using zirconium nitride and zirconium phosphide-modified bentonite

In this study, bentonite modified by zirconium nitride (ZrN) and zirconium phosphide (ZrP) catalysts was studied in the hydrocracking of crude palm oil to biofuels. The study demonstrated that bentonite was propitiously modified by ZrN and ZrP, as assessed by XRD, FTIR spectroscopy, and SEM-EDX analysis. The acidity of the bentonite catalyst was remarkably enhanced by ZrN and ZrP, and it showed an increased intensity in the Lewis acid and Brønsted acid sites, as presented by pyridine FTIR. In the hydrocracking application, the highest conversion was achieved by bentonite-ZrN at 8 mEq g⁻¹ catalyst loading of 87.93%, whereas bentonite-ZrP at 10 mEq g⁻¹ showed 86.04% conversion, which suggested that there was a strong positive correlation between the catalyst acidity and the conversion under a particular condition. The biofuel distribution fraction showed that both the catalysts produced a high bio-kerosene fraction, followed by bio-gasoline and oil fuel fractions. The reusability study revealed that both the catalysts had sufficient conversion stability of CPO through the hydrocracking reaction up to four consecutive runs with a low decrease in the catalyst activity. Overall, bentonite-ZrN dominantly favored the hydrocracking of CPO than bentonite-ZrP.

In this study, bentonite modified by zirconium nitride (ZrN) and zirconium phosphide (ZrP) catalysts was studied in the hydrocracking of crude palm oil to biofuels.

Catalytic Activation of Polyethylene Model Compounds Over Metal-Exchanged Beta Zeolites

Decomposition of polymers by heterogeneous catalysts presents a promising approach for reuse of waste plastics. We demonstrated non-hydrogenative decomposition of model polyolefins over proton-form and metal (Cu, Ni) ion-exchanged beta (BEA) zeolites at moderate temperatures (around 300 °C). Near complete polyolefin decomposition was observed in batch reactions monitored by thermogravimetric analysis, while decomposition at partial conversion was studied in flow reactions. Ni-exchanged zeolites produced H₂ at substantially higher rates (>10x) than other catalysts while also uniquely resisting deactivation over time. Application of the delplot formalism offered insights into the reaction network for polyolefin decomposition over Ni/BEA most notably that H₂ is solely a primary product. We deduce that H₂ production is catalyzed by activation of C-H bonds at ionic Ni sites, and H₂ prevents buildup of polyaromatic coke species in Ni-exchanged zeolites that deactivate Cu-exchanged and protonic zeolites.

A critical review on metal-based catalysts used in the pyrolysis of lignocellulosic biomass materials

This review discusses the technical aspects of improving the efficiency of the pyrolysis of lignocellulosic materials to increase the yield of the main products, which are bio-oil, biochar, and syngas. The latest aspects of catalyst development in the biomass pyrolysis process are presented focusing on the various catalyst structures, the physical and chemical performance of the catalysts, and the mode of the catalytic reaction. In bio-oil upgrading, atmospheric catalytic cracking is shown to be more economical than catalytic hydrotreating. Catalysts help in the upgrading process by facilitating several reaction pathways such as polymerization, aromatization, and alkyl condensation. However, the grade of bio-oil must be similar to that of diesel fuel. Hence, the properties of the pyrolysis liquid such as viscosity, kinematic viscosity, density, and boiling point are important and have been highlighted. Switching between types of catalysts has a significant influence on the final product yields and exhibits different levels of durability. Various catalysts have been shown to enhance gas yield at the expense of the yields of bio-oil and biochar that shift the overall purpose of pyrolysis. Therefore, the catalytic activity as a function of temperature, pressure, and catalyst biomass ratio is discussed in detail. These operational parameters are crucial because they determine the overall yield as well as the ratio of the oil, char, and gas products. Although significant progress has been made in catalytic pyrolysis, the economic feasibility of the process and the catalyst cost remain the major obstacles. This review concludes that the catalytic process would be feasible when the fuel selling price is reduced to less than US $ 4 per gallon of gasoline-equivalent, and when the selectivity of catalysts is further enhanced.

Techniques for analysing and monitoring during continuous bio-hydrogenation of kerosene from palm oils

In this research work, analytical, experimental methods and monitoring techniques of bio-hydrogenated kerosene (BHK) production in continuous mode were presented. Two kinds of raw materials obtained from palm processing plant named as refined bleached deodorised palm oil (RPO) and palm kernel oil (PKO) were converted into BHK via hydrocracking reaction catalysed by Pd/Al₂O₃ catalyst in pilot scale. Firstly, both of RPO and PKO were pretreated by thermal technique. Subsequently, fatty acid compositions of palm oils were analysed by Gas Chromatography (GC). Then, hydrocracking reaction of RPO and PKO were separately conducted in continuous high pressure packed bed reactor (HPPBR). After reaction, crude-biofuel was refined into BHK via fractional distillation. In addition, some properties of BHK obtained from RPO/PKO such as were C, H, O elements, freezing point, flash points, total acid number and carbon distribution were analysed following the ASTM and UOP 915 standards.•

Thermal pretreatment of refined bleached deoderised palm oil (RPO) and palm kernel oil (PKO).

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Continuous hydrocracking reaction of palm oil was conducted in pilot scale.

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Characterisation of bio-hydrogenated kerosene obtained from palm oil.