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Schematic drawing of Ni 12 P 5 and Ni formation on SiO 2 , ZSM-5 and Al 2 O 3 supports. [Display omitted] • Ni 12 P 5 crystal could effectively inhibit the coke formation on the catalysts. • High activity (95.4% conversion at 300 °C) was obtained on Ni 12 P 5 /SiO 2 catalyst. • Proper acidic sites and particle size of Ni 12 P 5 were responsible for high activity. Though nickel phosphides had been used widely to transform biomass into bio-fuel, the impact of support on the crystal formation was not clear. Herein, nickel and phosphides loaded on SiO 2 , ZSM-5 and γ-Al 2 O 3 were synthesized and the interaction between Ni/P and the supports was studied. Pure Ni 12 P 5 and pure Ni formed on SiO 2 and γ-Al 2 O 3 , respectively, whereas the mixture of Ni 12 P 5 and Ni formed on ZSM-5. The formation of AlPO 4 species was the main factor for the absence of Ni 12 P 5 on Ni/γ-Al 2 O 3 catalyst. Furthermore, the support also had a significant impact on the active phase with different particle size and dispersion, and further affected the performance. The highest fuel yield of 67.3 wt.% was obtained on Ni 12 P 5 /SiO 2 catalyst, which might be attributed to the appropriate acid sites and proper Ni 12 P 5 size. In addition, the catalysts with Ni 12 P 5 crystal phase displayed good resistance to coke deposition. The findings are important for clarification of the role of support in nickel phosphide active phase formation and coke deposition. [ABSTRACT FROM AUTHOR]

The hydrodeoxygenation (HDO) of renewable fats or fatty acids into alkanes is a powerful measure to address energy and environmental crises. Molybdenum carbide-based catalysts are promising due to their platinum-like noble metal electronic properties. In this paper, Mo2C catalysts were prepared by one-step carbonization of amine molybdenum oxide (AMO) precursors using diamines with different carbon chain lengths as ligands. The physical and chemical properties and the HDO catalytic activity of the catalysts were investigated. The results indicate that as the carbon chain of diamines in the precursor increases, the carbon content of the catalysts in the surface and bulk phase increases. The Mo2C-12 catalyst exhibited excellent catalytic performance, with a palmitic acid conversion rate of 100% and an alkane selectivity of 96.6%, which are attributed to the smallest particle size, largest pore size, and synergistic effect of carbon. This work provides a simple and safe method for regulating the surface properties of Mo2C catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • The coke resistance of Ni-based catalysts is improved profoundly by adding Er. • 99.3 % deoxygenation ratio and 64.7 % yield of biofuels is achieved on Ni-Er/50S-Al. • Er promotes the evenly distribution of Ni with smaller particle size. • More surface oxygen vacancies are critical for deoxygenating JO when REEs added. • The strong acidity leads to more coke form with Y added. Herein, three kinds of rare earth elements (Ce, Er and Y) were added to Ni-based catalysts to regulate the deoxygenation ability and coke resistance towards jatropha oil (JO) conversion. Among them, the catalysts with lanthanide metals (Ce and Er) added exhibit positive effects. Conversely, the addition of Y is counterproductive. The one with Er added displays the best catalytic performance, achieving the highest deoxygenation ratio (99.3 %) and product yield (64.7 %), and the resultant biofuel has the highest calorific value (46.02 MJ/kg). The stability of the Ni-Er/50S-Al catalyst is significantly improved due to the enhanced coke resistance compared with the one without Er added. Smaller Ni particle sizes with better dispersion, higher amount of surface Ni0 and surface oxygen vacancies are accomplished by adding Er, which contributes to the enhanced catalytic performance. The addition of Y weakens coke resistance, caused by strong acidity and big Ni particles. This study provides an effective idea for rationally designing catalysts with improved coke resistance and converting vegetable oils into biofuels. [ABSTRACT FROM AUTHOR]

[Display omitted] • The coke resistance of Ni-based catalysts is improved profoundly by adding Er. • 99.3 % deoxygenation ratio and 64.7 % yield of biofuels is achieved on Ni-Er/50S-Al. • Er promotes the evenly distribution of Ni with smaller particle size. • More surface oxygen vacancies are critical for deoxygenating JO when REEs added. • The strong acidity leads to more coke form with Y added. Herein, three kinds of rare earth elements (Ce, Er and Y) were added to Ni-based catalysts to regulate the deoxygenation ability and coke resistance towards jatropha oil (JO) conversion. Among them, the catalysts with lanthanide metals (Ce and Er) added exhibit positive effects. Conversely, the addition of Y is counterproductive. The one with Er added displays the best catalytic performance, achieving the highest deoxygenation ratio (99.3 %) and product yield (64.7 %), and the resultant biofuel has the highest calorific value (46.02 MJ/kg). The stability of the Ni-Er/50S-Al catalyst is significantly improved due to the enhanced coke resistance compared with the one without Er added. Smaller Ni particle sizes with better dispersion, higher amount of surface Ni0 and surface oxygen vacancies are accomplished by adding Er, which contributes to the enhanced catalytic performance. The addition of Y weakens coke resistance, caused by strong acidity and big Ni particles. This study provides an effective idea for rationally designing catalysts with improved coke resistance and converting vegetable oils into biofuels. [ABSTRACT FROM AUTHOR]

• The surface properties of NiCo/MCM-41 can be effectively tuned by pretreatment gas. • The largest amount of Lewis acid on NiCo/MCM-41-H promoted the HDO pathway. • NiCo/MCM-41-H can effectively convert jatropha oil into green biofuel. NiCo bimetallic catalyst was one of potential candidates used toward the hydrodeoxygenation of vegetable oils. However, there is still lack for digging out the relationship between micro-structure pretreated by various atmosphere and its catalytic performance. To hunting the relationship, NiCo/MCM-41 precursor was synthesized via the conventional co-impregnation method, and further pretreated by different atmospheres, including NH 3 , CH 4 /H 2 and H 2 in order to tune the particle size, active component dispersion, and acid properties of the catalysts. NiCo/MCM-41-H pretreated by H 2 exhibits superior catalytic performance (65.8 wt% biofuel yield and 98.2% C 12 -C 18 alkanes selectivity) on converting jatropha oil than that by NH 3 and by CH 4 /H 2. For comparison, the NiCo/MCM-41-H shows the smallest NiCo alloy grains, the smallest amount of strong acid, the lowest Brønsted acid/Lewis acid ratio, and the most uniform dispersion of Ni and Co. All the distinct surface properties of NiCo/MCM-41-H reasonably account for high efficiency in hydrodeoxygenation of jatropha oil. The work reveals the relationship between NiCo bimetallic catalyst structure and its hydrodeoxygenation performance, and provides a robust pretreatment method for tuning the surface properties to improve its catalytic performance for converting biomass oils into green biofuel. [ABSTRACT FROM AUTHOR]

[Display omitted] • A high bio-aviation fuel yield (63.5%) was obtained on 2%Pt/50%SAPO-11-50%γ-Al 2 O 3. • The obtained bio-aviation fuel had similar properties to commercial jet fuel. • The composite carrier catalyst exhibited better coke resistance compared to single ones. • The composite carrier was conducive to the generation of Pt with small particle size. Carbon deposition seriously affects the stability of catalyst, which restricts the industrialization of the one-step process for refining bio-aviation fuel. Pt supported on 50%SAPO-11-50%γ-Al 2 O 3 composite carrier was designed and synthesized, which presented enhanced coke resistance. The bio-aviation fuel with similar properties to the commercial jet fuel was obtained with a high yield of 63.5%. A series of characterization methods (including TG, XRD, H 2 -TPR, NH 3 -TPD, Py-IR, XPS, TEM and CO-pulse chemisorption) were utilized to reveal the structure characteristics of catalysts. TEM and CO-pulse chemisorption analysis indicates that the composite carrier is favorable for the dispersion of Pt with small active particles generated. The results from XPS, XRD and H 2 -TPR shows that the different ratios of Pt0/Pt4+ are generated due to the different interaction between Pt species and carriers. Py-IR results display that the composite carrier provides proper amount of Brønsted acid and Lewis acid sites correlated with the high bio-aviation fuel yield and enhanced coke resistance. The metallic platinum (Pt0) promotes the formation of Brønsted acid sites on catalysts, where excesses Brønsted acid sites causing the olefin polymerization, and inducing the formation of carbon deposition. The study offers an effective strategy to design the catalyst with excellent coke resistance by composite carrier effect toward refining bio-aviation fuel. [ABSTRACT FROM AUTHOR]

Tungsten carbide-based materials have good deoxygenation activity in the conversion of biomass. In this paper, catalysts with different nickel–tungsten carbide species were prepared by tuning the reduction temperature and Ni loading, and the effects of these different tungsten carbide species in the conversion of jatropha oil were studied. XRD, XPS, TEM, HRTEM, Raman, H2-TPR, ICP-AES were used to characterize the catalysts. The results suggested that metallic W was gradually carburized to W2C species, and W2C species was further carburized to WC species with the increase in reduction temperature and Ni loading. The obtained 10Ni10W/AC-700 catalyst exhibited outstanding catalytic performance with 99.7% deoxygenation rate and 94.5% C15-18 selectivity, which were attributed to the smallest particle size, the best dispersion, the most exposed active sites, and the synergistic effect of Ni, W2C and WC species. [ABSTRACT FROM AUTHOR]

The synthesis of new types of furan-based compounds other than 5-hydroxymethylfurfural from glucose is a very attractive yet underexploited strategy. We report here a catalytic conversion of glucose with acetylacetone (acac) to furan-centered chemicals, 2-methyl-3-acetylfuran (MAF) and 1-(5-(1,2-dihydroxyethyl)-2-methylfuran-3-yl)ethan-1-one (DMAF), which are potential building blocks for the synthesis of fine chemicals. The experimentally supported reaction mechanism is cascade-type, including glycolaldehyde (GA) formation by H2MoO4-catalysed retro-aldol condensation (C2 + C4) of glucose and immediate capture of transient C2 and C4 intermediates by acac to yield MAF and DMAF. To the best of our knowledge, this is the first report on the straightforward synthesis of MAF and DMAF from glucose, providing a new but generic synthesis strategy for GA-based C2 and erythrose-based C4 chemistry in biorefining. [ABSTRACT FROM AUTHOR]

xNi/HTASAO5 catalysts (x = 2.5, 3.3, 4.4, 5.8, 8.2) were prepared for CO 2 reforming of methane. No crystalline nickel species formed on the catalysts with lower nickel content (≤4.4%), and large Ni0 crystallite formed on 5.8% (10 nm) and 8.2 wt%Ni/HTASAO5 (17 nm), whereas the surface concentration of Ce3+ decreased with Ni loading. The initial conversion of CH 4 increased from 29.5% to 46.9% with Ni loading. The xNi/HTASAO5 (x ≤ 4.4%) performed stably in the reaction due to the presence of dispersed Ni species and high surface Ce3+ content without coke formation, however, 5.8% and 8.2 wt%Ni/HTASAO5 exhibited decreased activity with time on stream, because of the formation of large Ni particles with lower surface Ce3+, leading to carbon accumulation. Thus, CH 4 conversion stabilized at about 43% and no carbon formed on 4.4 wt%Ni/HTASAO5 with optimum Ni loading. 4.4 wt%Ni/HTASAO5 exhibited high activity and stability in DRM reaction with no coke formation. [Display omitted] • CH 4 conversion stabilized at 43% on 4.4 wt%Ni/HTASAO5 in DRM reaction at 600 °C. • No carbon deposited on the spent catalysts with no crystallite of Ni0. • Ce3+ concentration and adsorbed oxygen increases with decreasing Ni loading. • Reverse water gas shift reaction and carbon removal promoted by surface Ce3+. • The content of medium - strength basic sites increases with decreasing Ni loading. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni-Mo 2 N catalyst can be effectively convert jatropha oil into high-quality biofuel. • The HDO performance of Ni-Mo 2 N is significantly improved than that of Mo 2 N. • The synergy of Ni and Mo 2 N assists in high biofuel yield and deoxygenation ability. • The interaction between metal and support would affect the deoxygenation pathway. Mo 2 N catalyst can effectively remove oxygen from biomass oil under harsh reaction conditions. Herein, the innovative Ni-Mo 2 N/γ-Al 2 O 3 catalyst was synthesized through conventional impregnation method and NH 3 or N 2 /H 2 pretreatment. The hydrodeoxygenation performance of Ni-Mo 2 N/γ-Al 2 O 3 catalyst is significantly improved in comparison with Mo 2 N. At 320 °C and 3 MPa, the oxygen of jatropha oil is completely removed and high-quality biofuel with high selectivity of C 15 -C 18 hydrocarbons are obtained over the Ni-Mo 2 N/γ-Al 2 O 3 catalyst. This good reactivity for Ni-Mo 2 N/γ-Al 2 O 3 catalyst are ascribed to the synergistic effect of Ni and Mo 2 N, the most uniform Ni dispersion and the excellent coke resistance ability. Ni, as an auxiliary, is conductive to the cleavage of H–H bonds, while Mo 2 N are beneficial to the cleavage of C–O bonds. In addition, the metal-support interaction would affect the deoxygenation pathway of jatropha oil. This research proposes an efficient strategy for enhancing the hydrodeoxygenation performance of Mo 2 N catalysts for the jatropha oil conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • 10Ni-ZrO 2 exhibits high activity for the deoxygenation of methyl laurate. • 100% yield of alkanes and 87.6% selectivity to C 11 are obtained. • The Ni loading directs the formation of SOV and exposed lattice planes of t-ZrO 2. • The content of Ni0, SOV and Ni-O-Zr interfaces contribute to catalytic performance. • The exposed lattice planes of t-ZrO 2 play an important role in product distribution. A series of Ni-ZrO 2 catalysts with different Ni loading were prepared and evaluated for methyl laurate conversion. Characterizations show that the 10Ni-ZrO 2 bears the smallest Ni crystal size; the highest atomic content of surface Ni0, surface oxygen vacancy and Ni-O-Zr interfaces; then exhibits the highest activity and stability towards methyl laurate conversion with nearly 100% yield of alkanes and 87.6% selectivity to undecane at 280 °C, 2 MPa H 2. The t-ZrO 2 (1 1 2) lattice plane can motivate the deoxygenation while the t-ZrO 2 (0 0 2) promotes cracking reactions, resulting in low selectivity to undecane. Moreover, 10Ni-ZrO 2 performs wide applicability for transforming crude oils into alkanes. [ABSTRACT FROM AUTHOR]

• This work offers a comprehensive overview of the latest developments and future prospects in CCTUS technologies. • This work investigates the challenges and opportunities associated with the future adoption and advancement of CCTUS technologies. • This work serves as an invaluable resource for researchers and industry professionals seeking to CCTUS technologies. Carbon capture, transport, utilization, and storage (CCTUS) technologies are widely regarded as crucial solutions for mitigating the impacts of climate change. This review paper offers a comprehensive overview of the latest developments and future prospects in CCTUS technologies. The paper delves into the principles and applications of various CCTUS technologies. The advantages and disadvantages of each technology are explored, along with studies highlighting successful integration of CCTUS technologies. Additionally, the paper investigates the challenges and opportunities associated with the future adoption and advancement of CCTUS technologies. This review serves as an invaluable resource for researchers and industry professionals seeking to comprehend the present state and potential future of CCTUS technologies. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Nickel phosphides were known to be promising substitute for noble metal used in various catalysts. The traditional method of controlling the growth of nickel phosphide species, including Ni 2 P, Ni 3 P, and Ni 12 P 5 , was either modulating Ni/P molar ratio or changing support. Here, we report a new method to control the growth of nickel phosphide species by tuning the types of surface oxygenated group types on activated carbon. The pretreatment of activated carbon with HNO 3 remarkably increased the content of O C O groups. In the preparation process of activated carbon supported nickel phosphide catalyst, the O C O groups might interact with P to form P O C O groups. The formed P O C O inhibited the reduction of P species at low temperature, and thus inhibited the formation of the nickel phosphides; whereas at 873 K reduction, the formation of pure Ni 2 P on activated carbon was enhanced. However, the content of -OH groups content increased on activated carbon treated by NH 3 ∙H 2 O, which might be favorable for the simultaneous formation of Ni 2 P and Ni 12 P 5 with 1/1 ratio, and the thus formed catalyst displayed excellent catalytic hydrodeoxygenation activity for palmitic acid. Our results demonstrated how simple base and acid pretreatment could be used to tune the interfacial group distribution, hereby providing a strategy to rationally design transition metal phosphide supported catalysts. [ABSTRACT FROM AUTHOR]

• The dual effects of ABS on NH 3 -SCR performance of Fe 2 O 3 -WO 3 /MCM-41 is observed and illustrated for the first time. • The formation of surface metal sulfates sustainably promotes the catalytic performance. • Nearly 90% of sulfates in ABS are immobilized after NH 4 + consumption. • Both the acidity and redox properties of catalyst are greatly improved after metal sulfates formation. Ammonium bisulfate (ABS) has long been considered as a main poisoning material in the selective catalytic reduction by NH 3 (NH 3 -SCR) due to the inevitable coverage of sticky ABS on catalytic active sites in sulfur-containing atmospheres, which severely hinders the achievement of stable and highly active NH 3 -SCR catalysts. In the present study, we report a novel observation of the dual effects of ABS on the NH 3 -SCR reaction. That is, ABS inhibits the NH 3 -SCR performance of Fe 2 O 3 -WO 3 /MCM-41 catalyst at low temperatures (50–200 °C) but shows apparent and sustainable reaction promotion when the temperature surpasses 250 °C. X-ray photoelectron spectroscopy (XPS) and NO probing adsorption confirmed that when ABS is deposited on the catalyst surface, a partial interaction between ABS and the Fe 2 O 3 -WO 3 component occurs, resulting in blocking of the active sites and an obvious loss of catalytic activity. With increasing reaction temperature, the ammonium in ABS can be facilely consumed by NO/O 2 , thus inducing the disintegration of poisoning species. The sulfate group transforms into metal sulfate and survives at high temperatures. Importantly, owing to the strong inductive effect of sulfate species, both the acidity and redox properties of the catalyst are greatly improved, which contributes to the enhanced activity. The results of the present study expand our knowledge of the role of ABS in the NH 3 -SCR reaction and will be useful for designing high-performing NH 3 -SCR catalysts. [ABSTRACT FROM AUTHOR]

Pure Ni12P5/SiO2 and pure Ni2P/SiO2 catalysts were obtained by adjusting the Ni and P molar ratios, while Ni/SiO2 catalyst was prepared as a reference against which the deoxygenation pathways of palmitic acid were investigated. The catalysts were characterized by N2 adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission election microscopy (TEM), infrared spectroscopy of pyridine adsorption (Py-IR), H2-adsorption and temperature-programmed desorption of hydrogen (H2-TPD). The crystallographic planes of Ni(111), Ni12P5(400), Ni2P(111) were found mainly exposed on the above three catalysts, respectively. It was found that the deoxygenation pathway of palmitic acid mainly proceeded via direct decarboxylation (DCO2) to form C15 on Ni/SiO2. In contrast, on the Ni12P5/SiO2 catalyst, there were two main competitive pathways producing C15 and C16, one of which mainly proceeded via the decarbonylation (DCO) to form C15 accompanying water formation, and the other pathway produced C16 via the dehydration of hexadecanol intermediate, and the yield of C15 was approximately twofold that of C16. Over the Ni2P/SiO2 catalyst, two main deoxygenation pathways formed C15, one of which was mainly the DCO pathway and the other was dehydration accompanying the hexadecanal intermediate and then direct decarbonylation without water formation. The turn over frequency (TOF) followed the order: Ni12P5/SiO2 > Ni/SiO2 > Ni2P/SiO2. [ABSTRACT FROM AUTHOR]