ORALS

SESSION: EnergyThuPM2-R11	6th Intl. Symp. on Sustainable Energy Production: Fossil; Renewables; Nuclear; Waste handling , processing, and storage for all energy production technologies; Energy conservation
Thu Oct, 24 2019 / Room: Coralino
Session Chairs: Puzhen Gao; Sonja Stefanov; Session Monitor: TBA

16:20: [EnergyThuPM210]
Hydrogen Production via the Glycerol Steam Reforming using Ce-La-xCu Catalysts pt.2
Ayesha Alkhoori¹ ; Kyriaki Polychronopoulou¹ ; ¹Khalifa University, Abu Dhabi, United Arab Emirates;
Paper Id: 505 [Abstract]

An unintended consequence of the drive towards replacing petro-based sources in the transport sector and the subsequent growth of the biodiesel industry is the co-production of large amounts of crude glycerol (C₃H₈O₃) which constitutes the main by-product of the transesterification process [1-3]. A promising solution is its steam reforming since every mol of C₃H₈O₃ can theoretically produce 7 mol of H₂. Thus, research efforts are directed towards the discovery of cheap (i.e., transition metal based), highly active and stable catalysts. In the work presented herein, a series of Ce-La-xCu, (x=3, 5, 7, 10, 20 at.%) catalysts were evaluated for the glycerol steam reforming reaction in the 400-750^oC temperature range. Stability tests were conducted at 650^oC for 12h. The catalysts were prepared by coupling microwave radiation with the sol-gel method and BET, XRD, Raman, NH₃-TPD, CO₂-TPD, H₂-TPR, SEM, HAADF-STEM and XPS. These were used in order to derive information regarding their textural, morphological and physic-chemical properties to elucidate their effect on catalytic performance. The results obtained show that C₃H₈O₃ conversion of over 85% can be achieved with values for H₂ selectivity and approaches the yield of the thermodynamically predicted ones. The liquid effluents produced contained differing amounts of acetol, acetone, acetic acid, acrolein, allyl alcohol and acetaldehyde depending on the reaction temperature. Time-on-stream results, which were undertaken at more severe conditions, showed that all catalysts maintain quite a stable performance.

References:
[1] Papageridis, K.N.; Charisiou, N.D.; Siakavelas, G.; Avraam, D.G.; Tzounis, L.; Kousi, K.; Goula, M.A. Comparative study of Ni, Co, Cu supported on gamma-alumina catalysts for hydrogen production via the glycerol steam reforming reaction. Fuel Process. Technol. 2016, 152, 156-175.\n[2] Bepari, S.; Pradhan, N.C.; Dalai, A.K. Selective production of hydrogen by steam reforming of glycerol over Ni/Fly ash catalyst. Catal. Today 2017, 291, 36-46.\n[3] Goula, M.A.; Charisiou, N.D.; Pandis, P.K.; Stathopoulos, V.N. Ni/apatite-type lanthanum silicate supported catalyst for the glycerol steam reforming reaction. RSC Adv. 2016, 6, 78954-78958.

SESSION: EnergyThuPM2-R11	6th Intl. Symp. on Sustainable Energy Production: Fossil; Renewables; Nuclear; Waste handling , processing, and storage for all energy production technologies; Energy conservation
Thu Oct, 24 2019 / Room: Coralino
Session Chairs: Puzhen Gao; Sonja Stefanov; Session Monitor: TBA

16:45: [EnergyThuPM211]
Roles of Ni, Co and Cu Monometallic Catalysts Supported on ZrO2 for Green Diesel Production via the Palm Oil Hydrodeoxygenation
Nikolaos Charisiou¹ ; Steven J. Hinder² ; Mark A. Baker² ; Kyriaki Polychronopoulou³ ; Maria A. Goula¹ ; ¹Laboratory of Alternative Fuels and Environmental Catalysis, Department of Chemical Engineering, University of Western Macedonia, Kozani, Greece, Kozani, Greece; ²The Surface Analysis Laboratory, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, UK, Guildford, United Kingdom; ³Khalifa University, Abu Dhabi, United Arab Emirates;
Paper Id: 249 [Abstract]

Energy demand in the world is expected to increase by 59% by the year 2035 [1]. In addition, liquid transportation fuels from renewable resources are urgently needed due to the depletion of fossil resources. During the last 10 years intensive research efforts on biofuels, among them only green diesel, which can be synthesized either via catalytic hydrodeoxygenation or deoxygenation of triglycerides and fats, exhibits the same fuel properties as conventional diesel, since it has a similar composition. On the other hand, ethanol and butanol exhibit lower heating values and can suffer from incomplete burning thus forming oxygenated, harmful, gaseous by-products [2]. Moreover, biodiesel consisting of fatty acid methyl esters (FAMEs) has low oxidative stability, high viscosity and poor cold weather performance and is incompatible for large-scale use in conjunction with fossil fuels [3]. In the present work, we prepared ZrO₂-supported Ni, Co and Cu monometallic catalysts for the production of green diesel via hydrodeoxygenation of palm oil. The catalysts were prepared by the wet impregnation method and had the same metal loading (8 wt.%). The physical and chemical properties were determined by applying several characterization techniques including BET, XRD, NH3/CO2-TPD, TPR, XPS and TEM. Catalytic deoxygenation experiments were carried out in a fixed bed reactor (Autoclave Engineers BTRS) equipped with an HPLC pump. The SDO experiments were conducted using different operating parameters for the Ni/Zr catalyst, as follows: T=250-375°C, P=20-30 bar, LHSV=1.2-2.4 h^-1 and H₂/oil=250-2000 cm³/cm³, while for the Cu/Zr and Co/Zr samples the following operating parameters were used: T=300-400^oC, P=30 bar, LHSV=1.2 h^-1 and H₂/oil=1000 cm³/cm³. The results shows that the recommended conditions for the Ni/Zr were: I�=300 I�C, P = 30 bar, LHSV = 1.2 h^-1, H₂/oil ratio = 1000 cm³/cm³. Specifically, Palm oil was totally converted at 300 &#o176;C and the main reaction products were C₁₅ and C₁₇, with yields of 16 and 49 mol%, respectively, while C₁₅-C₁₈ n-alkane's yield was equal to 88 mol%. By comparing the three catalysts the deoxygenation activity decreased in the order of C₁₅-C₁₈ n-alkane's yield Ni > Cu > Co when compared at the same reaction temperatures. Also, to understand the roles of the three catalysts on the activity and selectivity in the deoxygenation reaction, the contributions of HDO and deCOx were estimated based on the mole balance corresponding to fatty acids in the oil feed. The Ni and Cu catalysts were favorable to the deCOx routes, whereas HDO was dominant over the Co catalyst.

References:
[1] X. Li, X. Luo, Y. Jin, J. Li, H. Zhang, A. Zhang, J. Xie, Renew. Sustain. Energy Rev. 82 (2018) 3762-3797.
[2] S. Douvartzides, N.D. Charisiou, K. N. Papageridis, M.A. Goula, Energies 12(5), 809 (2019).
[3] N.D. Charisiou, K. Polychronopoulou, A. Asif, M.A. Goula, Surf. Coatings Technol. (2018).

SESSION: AdvancedMaterialsFriPM1-R2	5th Intl. Symp. on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development
Fri Oct, 25 2019 / Room: Leda (99/Mezz. F)
Session Chairs: Lev Rapoport; Teofilo Rojo; Session Monitor: TBA

15:15: [AdvancedMaterialsFriPM108]
Coupling of Mechanochemical Synthesis with Enhanced Microwave Chemistry towards Biogas Dry Reforming Catalysts
Kyriaki Polychronopoulou¹ ; Sara Alkhoori¹ ; Aseel Hussien² ; ¹Khalifa University, Abu Dhabi, United Arab Emirates; ²Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates;
Paper Id: 252 [Abstract]

In the present study, enhanced microwave (EMW) synthesis, where microwave radiation is coupled with reflux conditions, was used to prepare CeO₂, CeO₂-La₂O₃, and CeO₂-La₂O₃-10% Cu catalysts. Ceria has become a promising material that features high redox properties, high population of oxygen vacancies [Ovac], that are crucial for hydrocarbon catalytic reactions such as CO₂ reformation of methane (dry reforming of biogas) [1-3]. This is crucial in the sense that they contribute to coke reduction. Post synthetically, the catalyst CeO₂-La₂O₃-10% Cu was ball milled under both, wet and dry conditions. The ball milling technique is expected to further improve the oxygen vacancies and give higher efficiency for uniform multi-component mixed oxides in consideration of time and energy usage. The prepared catalysts were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Remarkably, the EMW synthesis conditions affect the crystallinity of the catalysts (XRD) and the crystal growth, generating particles with crystallite size in the ranges of ~11-19 nm. The ball-milled catalysts exhibited a smaller crystallite size ~9.5 nm (XRD), which corresponds to larger surface area (m²/g). This, in fact, enhances oxygen mobility in the ceria support lattice and yields to the formation of more O vacancies.

References:
[1] ND Charisiou, G Siakavelas, L Tzounis, V Sebastian, A Monzon, MA Baker, SJ Hinder,
K Polychronopoulou, IV Yentekakis, MA Goula, International Journal of Hydrogen Energy
43 (41), 18955-18976
[2] ND Charisiou, K Polychronopoulou, A Asif, MA Goula Surface and Coatings Technology 352, 92-111
[3] ND Charisiou, A Iordanidis, K Polychronopoulou, IV Yentekakis, MA Goula
Materials Today: Proceedings 5 (14), 27607-27616

SESSION: AdvancedMaterialsSatPM3-R2	5th Intl. Symp. on New and Advanced Materials and Technologies for Energy, Environment and Sustainable Development
Sat Oct, 26 2019 / Room: Leda (99/Mezz. F)
Session Chairs: Natia Jalagonia; Roba Saab; Session Monitor: TBA

18:15: [AdvancedMaterialsSatPM314]
Hierarchical Porous Materials towards a Novel Hydrocracking Catalyst
Roba Saab¹ ; Kyriaki Polychronopoulou¹ ; Andreas Schiffer¹ ; ¹Khalifa University, Abu Dhabi, United Arab Emirates;
Paper Id: 246 [Abstract]

The use of heavy oils as fuel is becoming less favorable due to the environmental concerns associated with them, and thus, it is highly recommended to convert them into lighter high-value products. An important process in the conversion of such fuels is hydro-cracking, a process by which heavy chemicals are converted into lighter and added value products [1]. The development of zeolites as catalysts in hydrocracking has caused a major breakthrough due to their superior activity, stability, and gasoline selectivity as compared to amorphous silica-alumina catalysts [2]. Y-type zeolites with uniform crystal pore sizes and strong Brønsted acidity arising from the bridging OH groups are widely used as catalysts in industrial processes such as, hydrocracking, isomerization, and alkylation [3]. Nonetheless, carbon-zeolite composites seem to be interesting catalysts for hydrocracking in which the zeolite serves as a support for metal nanoparticles and provides an acidic cracking function. Meanwhile, the CNTs and graphene provide high thermal stability and conductivity, as well as a large specific surface area. To further increase the performance of existing hydrocracking catalysts, we demonstrate a novel approach for the synthesis of hybrid catalysts composed of Y-type zeolite, nickel nanoparticles and nano-carbon material (CNTs, Graphene). The zeolites, having a SiO₂/Al₂O₃ ratio of 30, were loaded with Ni, in 5 wt. %, using the wet impregnation method, and were hyberdized with CNTs. Despite their unique properties of high surface area and thermal conductivity, CNTs shall also add mesoporosity to the microporous zeolites, forming a hierarchical porous material. The synthesized catalyst was later tested for heptane hydrocracking at two different temperatures, 350°C and 400°C for 20 hours of time-on-stream.

References:
[1] H. B. Park, K. D. Kim, and Y. K. Lee, “Promoting asphaltene conversion by tetralin for hydrocracking of petroleum pitch,” Fuel, vol. 222, no. February, pp. 105-113, 2018.
[2] C. L. Hemler and L. F. Smith, “UOP fluid catalytic cracking Process,” in Hand book of Petroleum refining Processes, Third., McGraw-Hill, 2004.
[3] G. Busca, “Acidity and basicity of zeolites: A fundamental approach,” Microporous Mesoporous Mater., vol. 254, no. June 2016, pp. 3-16, 2017.

SESSION: NanomaterialsSatPM3-R8	6th Intl. Symp. on Synthesis and Properties of Nanomaterials for Future Energy Demands
Sat Oct, 26 2019 / Room: Ambrosia B (77/RF)
Session Chairs: Elizabeth Oliveira; Ayesha Alkhoori; Session Monitor: TBA

17:50: [NanomaterialsSatPM313]
Hydrogen Production via the Glycerol Steam Reforming using Ce-La-xCu Catalysts
Ayesha Alkhoori¹ ; Kyriaki Polychronopoulou¹ ; ¹Khalifa University, Abu Dhabi, United Arab Emirates;
Paper Id: 231 [Abstract]

An unintended consequence of the drive towards replacing petro-based sources in the transport sector and the subsequent growth of the biodiesel industry is the co-production of large amounts of crude glycerol (C₃H₈O₃) which constitutes the main by-product of the transesterification process [1-3]. A promising solution is its steam reforming since every mol of C₃H₈O₃ can theoretically produce 7 mol of H₂. Thus, research efforts are directed towards the discovery of cheap (i.e., transition metal based), highly active and stable catalysts. In the work presented herein, a series of Ce-La-xCu, (x=3, 5, 7, 10, 20 at.%) catalysts were evaluated for the glycerol steam reforming reaction in the 400-750^oC temperature range. Stability tests were conducted at 650^oC for 12h. The catalysts were prepared by coupling microwave radiation with the sol-gel method and BET, XRD, Raman, NH₃-TPD, CO₂-TPD, H₂-TPR, SEM, HAADF-STEM and XPS. These were used in order to derive information regarding their textural, morphological and physic-chemical properties to elucidate their effect on catalytic performance. The results obtained show that C₃H₈O₃ conversion of over 85% can be achieved with values for H₂ selectivity and approaches the yield of the thermodynamically predicted ones. The liquid effluents produced contained differing amounts of acetol, acetone, acetic acid, acrolein, allyl alcohol and acetaldehyde depending on the reaction temperature. Time-on-stream results, which were undertaken at more severe conditions, showed that all catalysts maintain quite a stable performance.

References:
[1] Papageridis, K.N.; Charisiou, N.D.; Siakavelas, G.; Avraam, D.G.; Tzounis, L.; Kousi, K.; Goula, M.A. Comparative study of Ni, Co, Cu supported on gamma-alumina catalysts for hydrogen production via the glycerol steam reforming reaction. Fuel Process. Technol. 2016, 152, 156-175.\n[2] Bepari, S.; Pradhan, N.C.; Dalai, A.K. Selective production of hydrogen by steam reforming of glycerol over Ni/Fly ash catalyst. Catal. Today 2017, 291, 36-46.\n[3] Goula, M.A.; Charisiou, N.D.; Pandis, P.K.; Stathopoulos, V.N. Ni/apatite-type lanthanum silicate supported catalyst for the glycerol steam reforming reaction. RSC Adv. 2016, 6, 78954-78958.