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An effective process to remove nitrogen-based compounds from fossil fuels without harming the process of sulfur removal is an actual gap in refineries. A success combination of desulfurization and denitrogenation processes capable of completely removing the most environmental contaminates in diesel under sustainable conditions was achieved in this work, applying polyoxometalates as catalysts, hydrogen peroxide as oxidant, and an immiscible ionic liquid as an extraction solvent. The developed process based in simultaneous oxidative desulfurization (ODS) and oxidative denitrogenation (ODN) involved initial extraction of sulfur and nitrogen compounds followed by catalytic oxidation. Keggin-type polyoxomolybdates revealed much higher reusing capacity than the related polyoxotungstate. Effectively, the first catalysts practically allowed complete sulfur and nitrogen removal only in 1 h of reaction and for ten consecutive cycles, maintaining the original catalyst and ionic liquid samples.
Dinis Silva; Alexandre Viana; Fátima Mirante; Baltazar de Castro; Luís Cunha-Silva; Salete Balula. Removing Simultaneously Sulfur and Nitrogen from Fuel under a Sustainable Oxidative Catalytic System. Sustainable Chemistry 2021, 2, 382 -391.
AMA StyleDinis Silva, Alexandre Viana, Fátima Mirante, Baltazar de Castro, Luís Cunha-Silva, Salete Balula. Removing Simultaneously Sulfur and Nitrogen from Fuel under a Sustainable Oxidative Catalytic System. Sustainable Chemistry. 2021; 2 (2):382-391.
Chicago/Turabian StyleDinis Silva; Alexandre Viana; Fátima Mirante; Baltazar de Castro; Luís Cunha-Silva; Salete Balula. 2021. "Removing Simultaneously Sulfur and Nitrogen from Fuel under a Sustainable Oxidative Catalytic System." Sustainable Chemistry 2, no. 2: 382-391.
High catalytic activity is found to be due to the combination of a chromium catalyst with large pores (MIL-101(Cr)) with aprotic solvents (γ-valerolactone−10% H2O).
Marta Lara-Serrano; Silvia Morales-Delarosa; Jose M. Campos-Martin; Víctor K. Abdelkader-Fernández; Luís Cunha-Silva; Salete S. Balula. Isomerization of glucose to fructose catalyzed by metal–organic frameworks. Sustainable Energy & Fuels 2021, 5, 3847 -3857.
AMA StyleMarta Lara-Serrano, Silvia Morales-Delarosa, Jose M. Campos-Martin, Víctor K. Abdelkader-Fernández, Luís Cunha-Silva, Salete S. Balula. Isomerization of glucose to fructose catalyzed by metal–organic frameworks. Sustainable Energy & Fuels. 2021; 5 (15):3847-3857.
Chicago/Turabian StyleMarta Lara-Serrano; Silvia Morales-Delarosa; Jose M. Campos-Martin; Víctor K. Abdelkader-Fernández; Luís Cunha-Silva; Salete S. Balula. 2021. "Isomerization of glucose to fructose catalyzed by metal–organic frameworks." Sustainable Energy & Fuels 5, no. 15: 3847-3857.
The application of a catalytic membrane in the oxidative desulfurization of a multicomponent model diesel formed by most refractory sulfur compounds present in fuel is reported here for the first time. The catalytic membrane was prepared by the impregnation of the active lamellar [Gd(H4nmp)(H2O)2]Cl·2H2O (UAV-59) coordination polymer (CP) into a polymethyl methacrylate (PMMA, acrylic glass) supporting membrane. The use of the catalytic membrane in the liquid–liquid system instead of a powder catalyst arises as an enormous advantage associated with the facility of catalyst handling while avoiding catalyst mass loss. The optimization of various parameters allowed to achieve a near complete desulfurization after 3 h under sustainable conditions, i.e., using an aqueous H2O2 as oxidant and an ionic liquid as extraction solvent ([BMIM]PF6, 1:0.5 ratio diesel:[BMIM]PF6). The performance of the catalytic membrane and of the powdered UAV-59 catalyst was comparable, with the advantage that the former could be recycled successfully for a higher number of desulfurization cycles without the need of washing and drying procedures between reaction cycles, turning the catalytic membrane process more cost-efficient and suitable for future industrial application.
Fátima Mirante; Ricardo Mendes; Rui Faria; Luís Cunha-Silva; Filipe Paz; Salete Balula. Membrane-Supported Layered Coordination Polymer as an Advanced Sustainable Catalyst for Desulfurization. Molecules 2021, 26, 2404 .
AMA StyleFátima Mirante, Ricardo Mendes, Rui Faria, Luís Cunha-Silva, Filipe Paz, Salete Balula. Membrane-Supported Layered Coordination Polymer as an Advanced Sustainable Catalyst for Desulfurization. Molecules. 2021; 26 (9):2404.
Chicago/Turabian StyleFátima Mirante; Ricardo Mendes; Rui Faria; Luís Cunha-Silva; Filipe Paz; Salete Balula. 2021. "Membrane-Supported Layered Coordination Polymer as an Advanced Sustainable Catalyst for Desulfurization." Molecules 26, no. 9: 2404.
The creation of more sustainable and high efficient desulfurization system, capable to operate under cost-effective conditions, led to the application of peroxopolyoxometalates as active oxidative catalysts. These compounds present active peroxo groups in their structure that promote easily the oxidation of sulfur compounds in the presence of low amounts of oxidant (H2O2/S = 4). The sustainability of the desulfurization of a multicomponent model diesel (2000 ppm S) was increased by the optimization of various parameters, such as nature and volume of extraction solvent, oxidant and catalyst. The Venturello peroxotungstate ((Bu4N)3PW4) showed to be a catalyst able to complete desulfurize a model diesel (after only 40 min), under lower amounts of solvent, oxidant and catalyst, than the analogues peroxomolybdate ((Bu4N)3PMo4) compound. Furthermore, the (Bu4N)3PW4/[BMIM]PF6 system was able to be reused for six consecutive desulfurization cycles maintaining its efficiency. The oxidized sulfur compounds were removed from [BMIM]PF6 phase in the end of each catalytic cycle. This simple procedure guarantees the cost-efficiency of the process, promoting the reuse of the catalyst and the solvent for various consecutive cycles, without the need of heterogenization techniques.
Yan Gao; Diana Julião; Dinis F. Silva; Baltazar de Castro; Jianshe Zhao; Salete S. Balula. A simple desulfurization process to achieve high efficiency, sustainability and cost-effectivity via peroxotungstate catalyst. Molecular Catalysis 2021, 505, 111515 .
AMA StyleYan Gao, Diana Julião, Dinis F. Silva, Baltazar de Castro, Jianshe Zhao, Salete S. Balula. A simple desulfurization process to achieve high efficiency, sustainability and cost-effectivity via peroxotungstate catalyst. Molecular Catalysis. 2021; 505 ():111515.
Chicago/Turabian StyleYan Gao; Diana Julião; Dinis F. Silva; Baltazar de Castro; Jianshe Zhao; Salete S. Balula. 2021. "A simple desulfurization process to achieve high efficiency, sustainability and cost-effectivity via peroxotungstate catalyst." Molecular Catalysis 505, no. : 111515.
In the current research, an advanced and innovative composite based in zeolitic imidazolate framework-8 (ZIF-8) incorporating magnetic and effective oxidative catalytic properties was successfully used to prepare ultra-low sulfur model and real fuels by oxidative desulfurization (ODS) process. To this purpose, the surface of ZIF-8 was decorated by TiO2 and Fe3O4 nanoparticles (NPs) to prepare the composite catalyst (Fe₃O₄/ZIF-8/TiO₂). Structural characterization was performed by XRD, FT-IR, SEM, EDS, TEM, N2 adsorption-desorption isotherm and VSM. TEM images showed that the semi-spherical TiO2 and Fe3O4 NPs are fairly doped. The effect of TiO2 and Fe3O4 NPs incorporated in ZIF-8 support allowed an efficient catalytic oxidative desulfurization of model fuel (500 ppm of dibenzothiophene, DBT) and real fuels (gasoline, diesel, among others) using tert-Butyl hydroperoxide (TBHP) as oxidant under a solvent-free system. Optimization studies were performed and complete desulfurization of model fuel was found after 6 h using O/S = 3 at 80 °C, instead of the 33% of desulfurization obtained with the pristine ZIF-8. Under optimized conditions, sulfone was the only product observed. The stability and the recycle capacity of the Fe₃O₄/ZIF-8/TiO₂ composite catalyst was confirmed and after ten consecutive ODS cycles only a slight decrease of desulfurization efficiency was detected (around 10%). Therefore, the results here presented confirm that the magnetic catalyst conciliates efficiency, stability and easy recovery, that are essential properties for future industrial application.
Hossein Kargar; Mahboube Ghahramaninezhad; Mahdi Niknam Shahrak; Salete S. Balula. An Effective Magnetic Catalyst for Oxidative Desulfurization of Model and Real Fuels: Fe3O4/ZIF-8/TiO₂. Microporous and Mesoporous Materials 2021, 317, 110992 .
AMA StyleHossein Kargar, Mahboube Ghahramaninezhad, Mahdi Niknam Shahrak, Salete S. Balula. An Effective Magnetic Catalyst for Oxidative Desulfurization of Model and Real Fuels: Fe3O4/ZIF-8/TiO₂. Microporous and Mesoporous Materials. 2021; 317 ():110992.
Chicago/Turabian StyleHossein Kargar; Mahboube Ghahramaninezhad; Mahdi Niknam Shahrak; Salete S. Balula. 2021. "An Effective Magnetic Catalyst for Oxidative Desulfurization of Model and Real Fuels: Fe3O4/ZIF-8/TiO₂." Microporous and Mesoporous Materials 317, no. : 110992.
A series of porous metal–organic frameworks (MOFs) of the UiO-66 family, namely UiO-66(Zr), UiO-66(Hf) and UiO-66(Hf)-NH2, prepared by solvothermal procedures were characterized, and their catalytic efficiency for oxidative denitrification (ODN) was investigated for the first time. Sustainable denitrogenation systems combining adsorption and oxidative catalytic capacity were designed using a model diesel containing two distinct nitrogen compounds (NCs) in a solvent-free medium and using an environment-friendly oxidant (H2O2). An efficient adsorptive denitrogenation process was only achieved after long reaction times (24 h): using the Hf-based MOFs, the adsorptive denitrogenation increased from 19% to 79% at 5 to 24 h, while the UiO-66(Zr) reached 76% after 24 h, although the absence of adsorption capacity after 5 h. UiO-66(Hf) and UiO-66(Hf)-NH2 also revealed superior oxidative catalytic denitrogenation than UiO-66(Zr), attaining 97% of efficiency instead of 80%. ODN processes demonstrated to be more effective than the adsorptive denitrogenation, mainly during the first hours of the process. In addition, the metal center in the MOF structure had a larger influence than the presence of the amine-functional groups. Hf-based compounds revealed higher denitrogenation efficiency than the UiO-66(Zr) for a shorter reaction time (5 h).
Rui G. Faria; Diana Julião; Salete S. Balula; Luís Cunha-Silva. Hf-Based UiO-66 as Adsorptive Compound and Oxidative Catalyst for Denitrogenation Processes. Compounds 2021, 1, 3 -14.
AMA StyleRui G. Faria, Diana Julião, Salete S. Balula, Luís Cunha-Silva. Hf-Based UiO-66 as Adsorptive Compound and Oxidative Catalyst for Denitrogenation Processes. Compounds. 2021; 1 (1):3-14.
Chicago/Turabian StyleRui G. Faria; Diana Julião; Salete S. Balula; Luís Cunha-Silva. 2021. "Hf-Based UiO-66 as Adsorptive Compound and Oxidative Catalyst for Denitrogenation Processes." Compounds 1, no. 1: 3-14.
A peroxotungstate composite comprising the chromium terephthalate metal–organic framework MIL-101(Cr) and the Venturello peroxotungstate [PO4{WO(O2)2}4]3− (PW4) has been prepared by the impregnation method. The [email protected](Cr) composite presents high catalytic efficiency for oxidative desulfurization of a multicomponent model diesel containing the most refractory sulfur compounds present in real fuels (2000 ppm of total S). The catalytic performance of this heterogeneous catalyst is similar to the corresponding homogeneous PW4 active center. Desulfurization efficiency of 99.7% was achieved after only 40 min at 70 °C using H2O2 as an oxidant and an ionic liquid as an extraction solvent ([BMIM]PF6, 2:1 model diesel/[BMIM]PF6). High recycling and reusing capacity was also found for [email protected](Cr), maintaining its activity for consecutive oxidative desulfurization cycles. A comparison of the catalytic performance of this peroxotungstate composite with others previously reported [email protected](Cr) catalysts indicates that the presence of active oxygen atoms from the peroxo groups promotes a higher oxidative catalytic efficiency in a shorter reaction time.
Yan Gao; Fátima Mirante; Baltazar De Castro; Jianshe Zhao; Luís Cunha-Silva; Salete S. Balula. An Effective Hybrid Heterogeneous Catalyst to Desulfurize Diesel: [email protected]–Organic Framework. Molecules 2020, 25, 5494 .
AMA StyleYan Gao, Fátima Mirante, Baltazar De Castro, Jianshe Zhao, Luís Cunha-Silva, Salete S. Balula. An Effective Hybrid Heterogeneous Catalyst to Desulfurize Diesel: [email protected]–Organic Framework. Molecules. 2020; 25 (23):5494.
Chicago/Turabian StyleYan Gao; Fátima Mirante; Baltazar De Castro; Jianshe Zhao; Luís Cunha-Silva; Salete S. Balula. 2020. "An Effective Hybrid Heterogeneous Catalyst to Desulfurize Diesel: [email protected]–Organic Framework." Molecules 25, no. 23: 5494.
Two quaternary ammonium catalysts based on the monovacant polyoxotungstate ([PW11O39]7−, abbreviated as PW11) were prepared and characterized. The desulfurization performances of the PW11-based hybrids (of tetrabutylammonium and trimethyloctadecylammonium, abbreviated as TBA[PW11] and ODA[PW11], respectively), the corresponding potassium salt (K7PW11O39, abbreviated as KPW11) and the peroxo-compound (TBA-PO4[WO(O2)2], abbreviated as TBA[PW4]) were compared as catalysts for the oxidative desulfurization of a multicomponent model diesel (2000 ppm S). The oxidative desulfurization studies (ODS) were performed using solvent-free systems and aqueous H2O2 as oxidant. The nature of the cation in the PW11 catalyst showed to have an important influence on the catalytic performance. In fact, the PW11-hybrid catalysts showed higher catalytic efficiency than the peroxo-compound TBA[PW4], known as Venturello compound. TBA[PW11] revealed a remarkable desulfurization performance with 96.5% of sulfur compounds removed in the first 130 min. The reusability and stability of the catalyst were also investigated for ten consecutive ODS cycles without loss of activity. A treated clean diesel could be recovered without sulfur compounds by performing a final liquid/liquid extraction diesel/EtOH:H2O mixture (1:1) after the catalytic oxidative step.
Fátima Mirante; Baltazar De Castro; Carlos M. Granadeiro; Salete S. Balula. Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst. Molecules 2020, 25, 4961 .
AMA StyleFátima Mirante, Baltazar De Castro, Carlos M. Granadeiro, Salete S. Balula. Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst. Molecules. 2020; 25 (21):4961.
Chicago/Turabian StyleFátima Mirante; Baltazar De Castro; Carlos M. Granadeiro; Salete S. Balula. 2020. "Solvent-Free Desulfurization System to Produce Low-Sulfur Diesel Using Hybrid Monovacant Keggin-Type Catalyst." Molecules 25, no. 21: 4961.
An ionic lamellar coordination polymer based on a flexible triphosphonic acid linker, [Gd(H4nmp)(H2O)2]Cl2 H2O (1) (H6nmp stands for nitrilo(trimethylphosphonic) acid), presents high efficiency to remove sulfur and nitrogen pollutant compounds from model diesel. Its oxidative catalytic performance was investigated using single sulfur (1-BT, DBT, 4-MDBT and 4,6-DMDBT, 2350 ppm of S) and nitrogen (indole and quinolone, 400 ppm of N) model diesels and further, using multicomponent S/N model diesel. Different methodologies of preparation followed (microwave, one-pot, hydrothermal) originated small morphological differences that did not influenced the catalytic performance of catalyst. Complete desulfurization and denitrogenation were achieved after 2 h using single model diesels, an ionic liquid as extraction solvent ([BMIM]PF6) and H2O2 as oxidant. Simultaneous desulfurization and denitrogenation processes revealed that the nitrogen compounds are more easily removed from the diesel phase to the [BMIM]PF6 phase and consequently, faster oxidized than the sulfur compounds. The lamellar catalyst showed a high recycle capacity for desulfurization. The reusability of the diesel/H2O2/[BMIM]PF6 system catalyzed by lamellar catalyst was more efficient for denitrogenation than for desulfurization process using a multicomponent model diesel. This behavior is not associated with the catalyst performance but it is mainly due to the saturation of S/N compounds in the extraction phase.
Fátima Mirante; Ricardo F. Mendes; Filipe A. Almeida Paz; Salete S. Balula. High Catalytic Efficiency of a Layered Coordination Polymer to Remove Simultaneous Sulfur and Nitrogen Compounds from Fuels. Catalysts 2020, 10, 731 .
AMA StyleFátima Mirante, Ricardo F. Mendes, Filipe A. Almeida Paz, Salete S. Balula. High Catalytic Efficiency of a Layered Coordination Polymer to Remove Simultaneous Sulfur and Nitrogen Compounds from Fuels. Catalysts. 2020; 10 (7):731.
Chicago/Turabian StyleFátima Mirante; Ricardo F. Mendes; Filipe A. Almeida Paz; Salete S. Balula. 2020. "High Catalytic Efficiency of a Layered Coordination Polymer to Remove Simultaneous Sulfur and Nitrogen Compounds from Fuels." Catalysts 10, no. 7: 731.
Increasing the POM loadings in [email protected] nanocomposites prepared in situ results in extremely modified framework electrocatalysts with highly enhanced OER performances.
Víctor K. Abdelkader-Fernández; Diana M. Fernandes; Salete S. Balula; Luís Cunha-Silva; Cristina Freire. Advanced framework-modified [email protected] nanocomposites as enhanced oxygen evolution reaction electrocatalysts. Journal of Materials Chemistry A 2020, 8, 13509 -13521.
AMA StyleVíctor K. Abdelkader-Fernández, Diana M. Fernandes, Salete S. Balula, Luís Cunha-Silva, Cristina Freire. Advanced framework-modified [email protected] nanocomposites as enhanced oxygen evolution reaction electrocatalysts. Journal of Materials Chemistry A. 2020; 8 (27):13509-13521.
Chicago/Turabian StyleVíctor K. Abdelkader-Fernández; Diana M. Fernandes; Salete S. Balula; Luís Cunha-Silva; Cristina Freire. 2020. "Advanced framework-modified [email protected] nanocomposites as enhanced oxygen evolution reaction electrocatalysts." Journal of Materials Chemistry A 8, no. 27: 13509-13521.
High efficiency was found for desulfurization and denitrogenation processes to treat diesel using either the hybrid material {[MoO3(2,2′‐bipy)][MoO3(H2O)]}n or the octanuclear complex [Mo8O22(OH)4(di‐t Bu‐bipy)4] (2,2′‐bipy = 2,2′‐bipyridine, di‐t Bu‐bipy = 4,4′‐di‐tert ‐butyl‐2,2′‐bipyridine)) as catalysts. These processes were employed in a single procedure to simultaneously remove the sulfur (dibenzothiophene, 4‐methyldibenzothiophene and 4,6‐dimethyldibenzothiophene) and nitrogen (indole and quinoline) compounds from diesel. A reaction time of 2 h was sufficient to achieve at least 99.9% S removal and 97% N removal. Furthermore, the catalytic systems presented a high capacity to be reused/recycled for consecutive desulfurization/denitrogenation cycles.
Diana Julião; Ana C. Gomes; Martyn Pillinger; Isabel S. Gonçalves; Salete S. Balula. Desulfurization and Denitrogenation Processes to Treat Diesel Using Mo(VI)‐Bipyridine Catalysts. Chemical Engineering & Technology 2020, 43, 1 .
AMA StyleDiana Julião, Ana C. Gomes, Martyn Pillinger, Isabel S. Gonçalves, Salete S. Balula. Desulfurization and Denitrogenation Processes to Treat Diesel Using Mo(VI)‐Bipyridine Catalysts. Chemical Engineering & Technology. 2020; 43 (9):1.
Chicago/Turabian StyleDiana Julião; Ana C. Gomes; Martyn Pillinger; Isabel S. Gonçalves; Salete S. Balula. 2020. "Desulfurization and Denitrogenation Processes to Treat Diesel Using Mo(VI)‐Bipyridine Catalysts." Chemical Engineering & Technology 43, no. 9: 1.
An unprecedented and straightforward strategy towards the activation of metal-organic frameworks UiO-66(Zr) and UiO-66(Hf) in oxidative desulfurization reactions was developed. Post-synthetic treatment of poor-defect pristine UiO-66 materials with chloride-based salts (for example TiCl4) leaded to the preparation of more active and recyclable heterogeneous catalysts for oxidative desulfurization processes. The pristine UiO-66(Hf) showed to be an inactive catalyst; however, after activation treatment 80% of total desulfurization was achieved after 1 h. Also, UiO-66 (Zr) increased appreciably its activity after treatment with chloride-based salts (from 62% from 97% after treatment with TiCl4). The insertion of chloride in UiO-66 framework did not retained the counter-cation Ti(IV). The possible interaction of chloride with UiO-66 framework enhances catalytic activity without structural degradation of catalyst, even after consecutive reaction cycles. Chloride activation method opened a new route to activate efficiently catalytic UiO-66 MOFs. This is a cost-effective method capable to be feasible to other MOFs structures, promoting their catalytic capacities and enlarging their catalytic application.
Alexandre Viana; Diana Julião; Fátima Mirante; Rui G. Faria; Baltazar de Castro; Salete S. Balula; Luís Cunha-Silva. Straightforward activation of metal-organic framework UiO-66 for oxidative desulfurization processes. Catalysis Today 2020, 362, 28 -34.
AMA StyleAlexandre Viana, Diana Julião, Fátima Mirante, Rui G. Faria, Baltazar de Castro, Salete S. Balula, Luís Cunha-Silva. Straightforward activation of metal-organic framework UiO-66 for oxidative desulfurization processes. Catalysis Today. 2020; 362 ():28-34.
Chicago/Turabian StyleAlexandre Viana; Diana Julião; Fátima Mirante; Rui G. Faria; Baltazar de Castro; Salete S. Balula; Luís Cunha-Silva. 2020. "Straightforward activation of metal-organic framework UiO-66 for oxidative desulfurization processes." Catalysis Today 362, no. : 28-34.
Novel material catalysts based in the active zinc-substituted polyoxotungstate ([PW11Zn(H2O)39]5-, abbreviated as PW11Zn) were efficiently used in the oxidative desulfurization of real and model diesels. These active catalytic center was strategically immobilized in a less hydrophilic periodic mesoporous organosilicas (PMOs), containing ethane-bridge (PMOE) and benzene-bridge (PMOB) walls, functionalized with (3-aminopropyl)triethoxysilane (aptes). The efficiency of the novel catalytic composites (PW11[email protected] and PW11[email protected]) was studied under oxidative desulfurization system (CODS) without the presence of an extraction solvent and also using a biphasic (diesel/extraction solvent) oxidative desulfurization system (ECODS). Both composites presented higher desulfurization efficiency under the solvent-free system, reaching ultra-low levels of sulfur compounds after only 1 h and using low ratio of H2O2/S = 4. The catalysts could be recycled without loss of activity for ten consecutive cycles. However, after the first desulfurization cycle complete desulfurization was achieved within only 30 min using PW11[email protected] composite. Also, the structure of PW11[email protected] demonstrated to be more stable than PW11[email protected], probably due to the occurrence of some PW11Zn leaching from the PMOB surface, probably caused by the lower interaction of PW11Zn with the benzene-bridge PMOB wall. The most robust catalyst PW11[email protected] was used to desulfurize a real diesel achieving 75.9% of desulfurization after 2 h. The catalyst was further recycled with success to treat real diesel.
Susana O. Ribeiro; Pedro L. Almeida; João Pires; Baltazar de Castro; Salete S. Balula. [email protected] mesoporous organosilicas as active materials for oxidative desulfurization of diesels. Microporous and Mesoporous Materials 2020, 302, 110193 .
AMA StyleSusana O. Ribeiro, Pedro L. Almeida, João Pires, Baltazar de Castro, Salete S. Balula. [email protected] mesoporous organosilicas as active materials for oxidative desulfurization of diesels. Microporous and Mesoporous Materials. 2020; 302 ():110193.
Chicago/Turabian StyleSusana O. Ribeiro; Pedro L. Almeida; João Pires; Baltazar de Castro; Salete S. Balula. 2020. "[email protected] mesoporous organosilicas as active materials for oxidative desulfurization of diesels." Microporous and Mesoporous Materials 302, no. : 110193.
Oxidative desulfurization (ODS) is a method of removing sulfur from diesel fuel that has the potential to complement or even replace conventional hydrodesulfurization processes in oil refineries. One of the most promising variants of ODS is extractive and catalytic ODS (ECODS) in which the organic sulfur compounds in the liquid fuel are oxidized and extracted in situ from the oil phase into an extractant phase. In this study, the desulfurization of model and real diesel fuel has been performed in ECODS systems employing two different types of deep eutectic solvents (DESs), prepared by combining polyethylene glycol (PEG) as hydrogen bond donor with tetrabutylammonium chloride (TBACl) or choline chloride (ChCl) as hydrogen bond acceptor. The ECODS systems were evaluated with the complexes [MoO2Cl2(DMB)2] (1) and [MoO2Cl2(DEO)] (2) (DMB = N,N-dimethylbenzamide, DEO = N,N′-diethyloxamide) as catalysts and 30 wt% H2O2 as oxidant. The effects of different reaction conditions, such as the amount of catalyst, H2O2 and DES, and reaction temperature, were investigated. The combination of complex 1 with the DES ChCl/PEG showed the best performance for the removal of dibenzothiophene, 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene from a high‑sulfur (3000 ppm) model diesel, allowing a desulfurization efficiency of 99.6% to be attained at 70 °C within 2 h. By applying the optimized model diesel ECODS systems to the treatment of a commercial untreated diesel with a sulfur content of 2300 ppm, 82% of sulfur compounds could be eliminated. These promising results indicate that DESs are a viable alternative to ionic liquids as extraction solvents in ECODS processes.
Diana Julião; Ana C. Gomes; Martyn Pillinger; André D. Lopes; Rita Valença; Jorge C. Ribeiro; Isabel S. Gonçalves; Salete S. Balula. Desulfurization of diesel by extraction coupled with Mo-catalyzed sulfoxidation in polyethylene glycol-based deep eutectic solvents. Journal of Molecular Liquids 2020, 309, 113093 .
AMA StyleDiana Julião, Ana C. Gomes, Martyn Pillinger, André D. Lopes, Rita Valença, Jorge C. Ribeiro, Isabel S. Gonçalves, Salete S. Balula. Desulfurization of diesel by extraction coupled with Mo-catalyzed sulfoxidation in polyethylene glycol-based deep eutectic solvents. Journal of Molecular Liquids. 2020; 309 ():113093.
Chicago/Turabian StyleDiana Julião; Ana C. Gomes; Martyn Pillinger; André D. Lopes; Rita Valença; Jorge C. Ribeiro; Isabel S. Gonçalves; Salete S. Balula. 2020. "Desulfurization of diesel by extraction coupled with Mo-catalyzed sulfoxidation in polyethylene glycol-based deep eutectic solvents." Journal of Molecular Liquids 309, no. : 113093.
A bidirectional synergy involving Co-based polyoxometalates (POMs) incorporated in the Co-containing zeolitic imidazolate framework, ZIF-67, that promoted a notable improvement in the oxygen evolution reaction (OER) performance was unveiled for the first time. Two [email protected] nanocomposite materials—[email protected] and [email protected]—were successfully prepared via a room temperature ‘in situ’ approach, by the immobilization of POM anions [SiW9Co3(H2O)3O37]10− (SiW9Co3) in the cages of two isostructural ZIFs: ZIF-8 and ZIF-67, formed with Zn2+ and Co2+, respectively. Despite both [email protected] and [email protected] revealed similar and low occupancy degrees (ca. 6 POM units per 100 ZIF-cages), an intense synergy has been detected in the ZIF-67 based nanocomposite, while no synergistic interaction was found for POMs and ZIF-8. Due to this synergetic effect, the OER activity of [email protected] is significantly enhanced in comparison with that of ZIF-67: ~110 mV decreased overpotential and double current density. Additionally, this nanocomposite exhibits excellent stability in the alkaline electrolyte. Insights into the nature and magnitude of the SiW9Co3–ZIF-67 synergy have shown up its interesting ZIF ↔ POM bidirectional nature that involves activation of the Co-based active sites in POM clusters as a consequence of a ZIF-67 → SiW9Co3 electron transfer, along with POM-induced generation of more active unsaturated Co-nodes in the ZIF-67 frameworks. These findings represent a promising ‘proof of concept’ for the development of more efficient [email protected] electrocatalysts in the future.
Víctor Karim Abdelkader Fernández; Diana Mesquita Fernandes; Salete Balula; Luís Cunha-Silva; Cristina Freire. Oxygen Evolution Reaction Electrocatalytic Improvement in [email protected] Nanocomposites: A Bidirectional Synergistic Effect. ACS Applied Energy Materials 2020, 3, 2925 -2934.
AMA StyleVíctor Karim Abdelkader Fernández, Diana Mesquita Fernandes, Salete Balula, Luís Cunha-Silva, Cristina Freire. Oxygen Evolution Reaction Electrocatalytic Improvement in [email protected] Nanocomposites: A Bidirectional Synergistic Effect. ACS Applied Energy Materials. 2020; 3 (3):2925-2934.
Chicago/Turabian StyleVíctor Karim Abdelkader Fernández; Diana Mesquita Fernandes; Salete Balula; Luís Cunha-Silva; Cristina Freire. 2020. "Oxygen Evolution Reaction Electrocatalytic Improvement in [email protected] Nanocomposites: A Bidirectional Synergistic Effect." ACS Applied Energy Materials 3, no. 3: 2925-2934.
Regulations on the permissible levels of sulfur in transportation fuels are becoming ever more strict, with a global shift towards “zero sulfur” fuels, and the revamp of existing hydrodesulfurization (HDS) facilities to meet these lower caps is cost‐prohibitive. Metal‐catalyzed sulfoxidation chemistry is viewed as an economically viable desulfurization strategy that could complement conventional HDS technology. In the present work, the complex [η5‐IndMo(CO)3Me] (1) (Ind = indenyl) was employed in the catalytic oxidative desulfurization (CODS) of model and real liquid fuels, using aqueous hydrogen peroxide (H2O2) as oxidant. After optimization of the CODS reaction parameters (diesel/H2O2 ratio, catalyst amount, temperature), a high‐sulfur (2000 ppm) model diesel containing benzothiophene, dibenzothiophene, 4‐methyldibenzothiophene and 4,6‐dimethyldibenzothiophene could be completely desulfurized within 2 hr under solvent‐free conditions or in the presence of the ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([BMIM]PF6) as extraction solvent. The catalyst formed under solvent‐free conditions could be recycled without a significant decrease in desulfurization activity. The high performance of the CODS system was verified in the sulfur removal from a commercial untreated diesel fuel with a sulfur content of 2300 ppm, and a jet fuel with a sulfur content of 1100 ppm. Solvent‐free CODS in combination with initial/final extraction gave desulfurization efficiencies of 70% for the diesel fuel and 55% for the jet fuel. CODS with [BMIM]PF6 in combination with initial/final extraction led to a sulfur removal of 95.9% for the diesel fuel, which is one of the best results yet reported for ODS of commercial diesels.
Diana Julião; Ana C. Gomes; Martyn Pillinger; Rita Valença; Jorge C. Ribeiro; Isabel S. Gonçalves; Salete S. Balula. Desulfurization of model and real fuels by extraction and oxidation processes using an indenylmolybdenum tricarbonyl pre‐catalyst. Applied Organometallic Chemistry 2020, 34, 1 .
AMA StyleDiana Julião, Ana C. Gomes, Martyn Pillinger, Rita Valença, Jorge C. Ribeiro, Isabel S. Gonçalves, Salete S. Balula. Desulfurization of model and real fuels by extraction and oxidation processes using an indenylmolybdenum tricarbonyl pre‐catalyst. Applied Organometallic Chemistry. 2020; 34 (4):1.
Chicago/Turabian StyleDiana Julião; Ana C. Gomes; Martyn Pillinger; Rita Valença; Jorge C. Ribeiro; Isabel S. Gonçalves; Salete S. Balula. 2020. "Desulfurization of model and real fuels by extraction and oxidation processes using an indenylmolybdenum tricarbonyl pre‐catalyst." Applied Organometallic Chemistry 34, no. 4: 1.
The monolacunary Keggin-type [PW11O39]7− (PW11) heteropolyanion was immobilized on porous framework of mesoporous silicas, namely SBA-15 and an ethylene-bridged periodic mesoporous organosilica (PMOE). The supports were functionalized with a cationic group (N-trimethoxysilypropyl-N, N, N-trimethylammonium, TMA) for the successful anchoring of the anionic polyoxometalate. The [email protected] and [email protected] composites were evaluated as heterogeneous catalysts in the oxidative desulfurization of a model diesel. The [email protected] catalyst showed a remarkable desulfurization performance by reaching ultra-low sulfur levels (<10 ppm) after only 60 min using either a biphasic extractive and catalytic oxidative desulfurization (ECODS) system (1:1 MeCN/diesel) or a solvent-free catalytic oxidative desulfurization (CODS) system. Furthermore, the mesoporous silica composite was able to be recycled for six consecutive cycles without any apparent loss of activity. The promising results have led to the application of the catalyst in the desulfurization of an untreated real diesel supplied by CEPSA (1,335 ppm S) using the biphasic system. The system has proved to be a highly efficient process by reaching desulfurization values higher than 90% for real diesel during three consecutive cycles.
Susana O. Ribeiro; Carlos Granadeiro; Marta Corvo; João Pires; Jose M. Campos-Martin; Baltazar de Castro; Salete S. Balula. Mesoporous Silica vs. Organosilica Composites to Desulfurize Diesel. Frontiers in Chemistry 2019, 7, 1 .
AMA StyleSusana O. Ribeiro, Carlos Granadeiro, Marta Corvo, João Pires, Jose M. Campos-Martin, Baltazar de Castro, Salete S. Balula. Mesoporous Silica vs. Organosilica Composites to Desulfurize Diesel. Frontiers in Chemistry. 2019; 7 ():1.
Chicago/Turabian StyleSusana O. Ribeiro; Carlos Granadeiro; Marta Corvo; João Pires; Jose M. Campos-Martin; Baltazar de Castro; Salete S. Balula. 2019. "Mesoporous Silica vs. Organosilica Composites to Desulfurize Diesel." Frontiers in Chemistry 7, no. : 1.
A novel composite has been prepared through the immobilization of the Keggin sandwich-type [Sm(PMo11O39)2]11− anion (SmPOM) on large-pore silica spheres previously functionalized with trimethylammonium groups (TMA). The resulting [email protected] material has been evaluated as heterogeneous catalyst in a biphasic desulfurization 1:1 diesel/extraction solvent system using H2O2 as oxidant. Preliminary experiments were conducted with different extraction solvents, acetonitrile and [BMIM]PF6 ionic liquid. The optimized extractive and catalytic oxidative desulfurization system (ECODS) with [BMIM]PF6 was able to reach complete sulfur removal from a model diesel containing 2100 ppm S in just 60 min (10 min of initial extraction + 50 min of catalytic step). The reutilization of catalyst and extraction phase has been successfully performed without loss of desulfurization efficiency in consecutive cycles, turning the process more sustainable and cost-effective. The remarkable results with simulated diesel have motivated the application of the catalyst in the desulfurization of untreated real diesel and 74% of efficiency was achieved after only 2 h for three consecutive cycles.
Fátima Mirante; Ana C. Alves; Diana Julião; Pedro Marques de Almeida; Sandra Gago; Rita Valençad; Jorge C. Ribeiro; Baltazar de Castro; Carlos M. Granadeiro; Salete S. Balula. Large-pore silica spheres as support for samarium-coordinated undecamolybdophosphate: Oxidative desulfurization of diesels. Fuel 2019, 259, 116213 .
AMA StyleFátima Mirante, Ana C. Alves, Diana Julião, Pedro Marques de Almeida, Sandra Gago, Rita Valençad, Jorge C. Ribeiro, Baltazar de Castro, Carlos M. Granadeiro, Salete S. Balula. Large-pore silica spheres as support for samarium-coordinated undecamolybdophosphate: Oxidative desulfurization of diesels. Fuel. 2019; 259 ():116213.
Chicago/Turabian StyleFátima Mirante; Ana C. Alves; Diana Julião; Pedro Marques de Almeida; Sandra Gago; Rita Valençad; Jorge C. Ribeiro; Baltazar de Castro; Carlos M. Granadeiro; Salete S. Balula. 2019. "Large-pore silica spheres as support for samarium-coordinated undecamolybdophosphate: Oxidative desulfurization of diesels." Fuel 259, no. : 116213.
Porous metal-organic framework (MOF) materials UiO-66(Zr) obtained by solvothermal and microwave advanced synthesis (MWAS) procedures were characterized, and their catalytic efficiency was investigated for oxidative desulfurization (ODS) processes using a multicomponent model diesel containing benzothiophene and dibenzothiophene derivatives. The preparation parameters as the cooling time after oven use in the solvothermal procedure, and also the reaction time in the MWAS method seemed to play an important role in the catalytic performance of the UiO-66(Zr) material, as well as in its recycle capacity. The material prepared by the solvothermal procedure with a fast cooling time showed the best catalytic performance (desulfurization efficiency of 99.5% after 3 h). However, the application of the UiO-66(Zr) material prepared by the MWAS method (desulfurization efficiency of 96% after 3 h) conciliated a higher number of advantages, such as shorter reaction time preparation (15 min) and high catalytic activity for a higher number of reaction cycles. The UiO-66(Zr) prepared by the MWAS method was used for the first time in an oxidative desulfurization process, and according to the catalytic results obtained (high recycle capacity and stability) and shorter reaction time preparation, seems to be a promising material for industrial application.
Alexandre Viana; Susana O. Ribeiro; Baltazar De Castro; Salete S. Balula; Luís Cunha-Silva. Influence of UiO-66(Zr) Preparation Strategies in Its Catalytic Efficiency for Desulfurization Process. Materials 2019, 12, 3009 .
AMA StyleAlexandre Viana, Susana O. Ribeiro, Baltazar De Castro, Salete S. Balula, Luís Cunha-Silva. Influence of UiO-66(Zr) Preparation Strategies in Its Catalytic Efficiency for Desulfurization Process. Materials. 2019; 12 (18):3009.
Chicago/Turabian StyleAlexandre Viana; Susana O. Ribeiro; Baltazar De Castro; Salete S. Balula; Luís Cunha-Silva. 2019. "Influence of UiO-66(Zr) Preparation Strategies in Its Catalytic Efficiency for Desulfurization Process." Materials 12, no. 18: 3009.
The Keggin phosphotungstate (PW12) and its zinc derivative (PW11Zn) were tested as oxidative catalysts for desulfurization processes using simulated and real diesels. These compounds were used as homogeneous while the corresponding SBA-15 composites as heterogeneous catalysts. The comparison of their catalytic performance demonstrated that the zinc-substituted POM is more efficient than the plenary PW12 structure. Additionally, using the heterogeneous PW11[email protected], the sustainability and the catalytic efficiency was largely improved, allowing the total sulfur removal from model diesel after 1 h using a small amount of oxidant (H2O2/S = 4) under an oxidative solvent-free system. The desulfurization of real diesels was performed under similar conditions, achieving 87.8% of efficiency using PW11[email protected] catalyst. Furthermore, the catalyst maintained its activity over consecutive desulfurization cycles. The cost-effective operational conditions achieved with PW11[email protected], turn this a promising material to be used in an industrial scale to treat diesel.
Susana O. Ribeiro; Carlos M. Granadeiro; Pedro L. Almeida; João Pires; Rita Valença; Jose Miguel Campos-Martin; Jorge C. Ribeiro; Baltazar de Castro; Salete Silva Balula. Effective Zinc-Substituted Keggin Composite To Catalyze the Removal of Sulfur from Real Diesels under a Solvent-Free System. Industrial & Engineering Chemistry Research 2019, 58, 18540 -18549.
AMA StyleSusana O. Ribeiro, Carlos M. Granadeiro, Pedro L. Almeida, João Pires, Rita Valença, Jose Miguel Campos-Martin, Jorge C. Ribeiro, Baltazar de Castro, Salete Silva Balula. Effective Zinc-Substituted Keggin Composite To Catalyze the Removal of Sulfur from Real Diesels under a Solvent-Free System. Industrial & Engineering Chemistry Research. 2019; 58 (40):18540-18549.
Chicago/Turabian StyleSusana O. Ribeiro; Carlos M. Granadeiro; Pedro L. Almeida; João Pires; Rita Valença; Jose Miguel Campos-Martin; Jorge C. Ribeiro; Baltazar de Castro; Salete Silva Balula. 2019. "Effective Zinc-Substituted Keggin Composite To Catalyze the Removal of Sulfur from Real Diesels under a Solvent-Free System." Industrial & Engineering Chemistry Research 58, no. 40: 18540-18549.