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Lignocellulose biomass was converted to jet fuel range naphthenic fuel by “cyclopentanone-vanillin” strategy using hemi/cellulose-derived cyclopentanones and lignin-derived vanillin as platform compounds.

The “dragonfruit” structured catalyst with ultra-small Fe3O4nanoparticles evenly dispersed inside an acidic and slightly mesoporous Al-ZSM-5, exhibits high selectivity in the direct conversion of syngas into aromatics and also presents excellent sintering resistance.

The purpose of this clinical trial was to evaluate the preventive effects of different doses of atorvastatin on CI-AKI in patients after CT perfusions. 688 patients undergoing CT perfusions were administered doses of atorvastatin (20 mg/day, n = 164), atorvastatin (40 mg/day, n = 178), atorvastatin (60 mg/day, n = 176) and placebo (40 mg/day, n = 170). Several factors, urinary neutrophil gelatinase-associated lipocalin (NGAL) levels, protein kinase C (PKC), nuclear factor erythroid-2 related factor 2 (Nrf2), nicotinamide adenine dinucleotide phosphate (NADPH) responsible for contrast-induced acute kidney necrosis were recorded in this study. Postoperative administration of atorvastatin decreased the risk of CI-AKI and improved renal function. 60 mg/day of atorvastatin showed best preventive effect on CI-AKI in three groups determined by Charlson Cormobidity Index (CCI) and risk, injury, failure, loss, end-stage renal disease (RIFLE). 60 mg/day of atorvastatin significantly decreased the inflammatory cytokines interleukin (IL)-1β, transforming growth factor (TGF)-β, and tumor necrosis factor (TNF)-α compared to 20 mg/day and 40 mg/day of atorvastatin in patients after multiple CT perfusions. NADPH oxidase 4 (NOX4) and p22phox expression was reduced by atorvastatin treatment. In conclusion, these outcomes indicate that 60 mg/day of atorvastatin treatment reduces the risk of CI-AKI in patients after multiple CT perfusions.

Highly effective production of 5-hydroxymethylfurfural (HMF) from biobased sugar is one of the vital steps for the synthesis of a fuel precursor. In this work, a slow-release effect of proton from a heterogeneous catalyst induced by 1-butyl-3-methylimidazole chloride ([Bmim]Cl) ionic liquids was found and employed to effectively convert biobased fructose to HMF. Under mild conditions of 100 °C and 60 min, a promising HMF yield of 94.6% with a fructose conversion of 99.1% could be achieved in a tetrahydrofuran solvent over the synergy of Amberlyst-15 with [Bmim]Cl, owing to the slow-release effect. Based on extensive control experiments and characterizations, a mechanism of slow release of proton induced by [Bmim]Cl was proposed to better understand the catalytic performance, mainly involving that proton in the −SO3H group of Amberlyst-15 was gradually replaced by the [Bmim]+of the [Bmim]Cl additive. Additionally, the effect of various parameters (e.g., different ionic liquids and solvents, the loading of the ionic liquid and catalyst, and reaction temperature and time) was systematically investigated. Meanwhile, the stability of Amberlyst-15 and [Bmim]Cl was tested; both could be reused four times. This work provides a novel and highly effective strategy for conversion of biomass-based feedstock toward fuel precursors.

Efficient and one-pot conversion of biomass-derived carbohydrate into highly value-added 5-hydroxymethylfurfural (HMF) is a crucial reaction step for the valorization of biomass resources toward bio-based chemicals and fuels. In this work, a series of Sn/SAPO-34 catalysts were prepared through impregnation and evaluated in glucose conversion to HMF. The physicochemical properties of Sn/SAPO-34 catalysts were systematically characterized by SEM, XRD, N2physisorption, XPS, solid-state 119Sn, 29Si, and 31P NMR, XRF, UV–vis, NH3-TPD, and pyridine-FTIR techniques. It was demonstrated that controlling the Sn loading amount could facilely adjust the acid strength and acid amount of the SAPO-34 zeolite. The incorporation of Sn species could induce the formation of a tetrahedrally coordinated Sn4+site and Sn-OH site to improve the amounts of Brønsted and Lewis acid sites of the catalyst. However, modification with sufficiently high Sn loading could decrease the acid strength and performance of the catalyst owing to its structure damage. The 5%Sn/SAPO-34 catalyst (i.e., Sn loading calculated based on the mass ratio of SnCl4·5H2O as a precursor to the parent SAPO-34) was found to exhibit the superior catalytic performance under mild conditions and could afford an HMF yield of 64.4% at 98.5% glucose conversion in a biphasic 35 wt % NaCl-H2O/tetrahydrofuran (THF) system at 150 °C within 1.5 h. Additionally, a catalytic reaction pathway was proposed, involving the adsorption of glucose molecules by the −Cl group on the catalyst via a hydrogen bond, followed by glucose isomerization to fructose over the Lewis acid Sn4+and Al3+sites and, finally, fructose dehydration to HMF catalyzed by the Brønsted acid Sn-OH and Si-OH-Al sites. The activity of the catalyst decreased due to the leaching of the active site Sn after several consecutive cycles. This work provides insights into the improvement in the Sn-containing zeolite catalyst for tandem conversion of glucose to HMF.

Furfural (FAL), a promising renewable platform compound from biomass, can be totally hydrogenated to an industrially important platform chemical, tetrahydrofurfuryl alcohol (THFA). In this work, a high yield of THFA was obtained by one-pot hydrogenation of FAL over a PtNi catalyst under mild reaction conditions. Small PtNi alloy particles were well distributed on active carbon. The catalysts were characterized by several physical–chemical technologies (transmission electron microscopy, X-ray diffraction, energy-dispersive spectroscopy, and inductively coupled plasma spectroscopy). Temperature-programmed reduction with hydrogen and in situ X-ray photoelectron spectroscopy demonstrate the presence of PtNi alloy. The electron-rich metal Pt could facilitate the heterolytic dissociation of hydrogen and promote the hydrogenation of FAL. Pt sites on the surface facilitate the adsorption at aldehyde (C═O) groups, and the furan ring strongly adsorbs on the Ni surface. Low reaction temperature is advantageous to reduce side reactions. Various metal concentrations were employed in this reaction; Pt(3)Ni(3)/C catalyst exhibits the best performance, achieving 99% FAL conversion and 93% THFA yield at 35 °C and under 2 MPa H2.

In this work, manganese well-dispersed on Fe3O4microsphere (Mn–Fe3O4) catalyst was synthesized. It exhibited excellent catalytic performance for the direct conversion of carbon dioxide (CO2) into light olefins. A CO2conversion of 44.7% with high selectivity of light olefin (46.2%, yield of 18.7%), high O/P ratio (6.5), and low selectivity of CO (9.4%) was obtained over the 10Mn–Fe3O4catalyst. The Mn–Fe3O4catalyst was studied by XRD, SEM, (HR)TEM, STEM–EDS, H2-TPR, and CO2-TPD. The result indicated that the manganese promoter could facilitate the adsorption of CO2and the activation of C═O bonds as well as inhibit the secondary hydrogenation. This work offered a novel Fe-based catalyst system to the utilization of CO2and an understanding in promoting C═O bond activation in the first step of CO2hydrogenation to hydrocarbon reaction.

By using small-sized metal particles homogeneously dispersed on a support, the performance of a catalyst can be improved and high-cost metal can be saved. Preparing homogeneously dispersed Ag0/g-C3N4as a N2photofixation catalyst is a challenge. In the past, for its preparation as a photocatalyst, surfactants have to be used, and the preparation process is time consuming and high cost. Herein, a one-pot method is used to prepare homogeneously dispersed Ag0/g-C3N4as an efficient N2photofixation catalyst by the reduction–deposition method at ultra-low temperature (−60 °C). The characterizations and N2photofixation results show that small-sized Ag particles promote N2adsorption and generate more photo-generated electrons–holes. Meanwhile, they improve the electron/hole separation efficiency. The N2photocatalytic activity of the catalyst is 1.4 and 15 times higher than that of larger-sized Ag/C3N4and pristine C3N4, respectively. The advantages of the catalyst are saving Ag, quantum size effects, and improving metal–support interactions. The process can be used to prepare state-of-the-art photocatalysts for N2photofixation.

Herein, we reported in situ synthesis of biomass-derived Ni/C catalyst by self-reduction with pomelo peel. Compared with the conventional method, which includes carbonization, activation, impregnation and reduction, the entire preparation process was simplified to two steps, which was more straightforward. This synthesis method was green as Ni/C can be prepared without any additional chemical and the self-reduction process was realized in N2, which can avoid using H2thus averting some problems such as storage, transportation and safety of H2. Meanwhile, the size and dispersion of Ni particles can be controlled by changing carbonization temperature. The synthesis mechanism of Ni/C catalyst with self-reduction was investigated, which was mainly attributed to the carbon and reducing gas produced during the carbonization process. For the catalytic performance of GVL synthesis, a high yield (94.5%) can be obtained and it exhibited good stability up to 5 cycles without obvious loss of catalytic activity.

Mapping and understanding humin coking during carbohydrate conversion is crucial for improving solid catalyst systems. However, models for coke mapping are still in need of development. In this study, a lattice Boltzmann method-based back-propagation artificial neural network reduced-order model (ROM) is developed to map the humin distribution during the conversion process. The ROM reveals three configurations of intraparticle coking distribution (surface focus, middle-layer focus, and central focus coking). The experimental feature of surface-focus configuration is the timely decreasing trend in the macroscopic coke accumulation rate, especially under extreme conditions (surface humins/central humins >10). Catalyst load, pellet size, substrate concentration (LSC), and temperature collectively influence the coking configurations. As the temperature increases (100–160 °C), the configuration with the highest occupancy in the LSC coordinate space changes from central to middle-layer and finally to surface configuration. Increasing the catalyst loading, reducing the particle size, and lowering the substrate concentration under a threshold number (φLSC) in LSC space helps prevent the catalyst from working under the extreme surface coking configuration status.

Hydrodeoxygenation of vegetable oils and fats is an effective method for the production of high-quality hydrocarbon fuels. Herein, a series of metallic oxides supported on SAPO-11 were developed for the hydrodeoxygenation of methyl palmitate or palm oil to hydrocarbon fuels under mild conditions. The nitrogen-functionalized bimetallic oxide catalyst (NiO–MoO3@N/SAPO-11) exhibited the highest catalytic activity, obtaining methyl palmitate and palm oil conversion close to 100% and aviation fuel selectivity of 93.14% at 280 °C. In the hydroprocessing of methyl palmitate, the metal Ni and oxygen vacancies produced in situ by partial reduction play an indispensable role in the activation of hydrogen and the adsorption of oxygen-containing functional groups. Moreover, pyridinic-N was introduced to the NiO–MoO3@N/SAPO-11 catalyst, producing a high selectivity for the decarboxylation in the hydroprocessing of methyl palmitate.

CH4is a clean fuel due to the highest H/C atom ratio among the other hydrocarbon fuels, showing less carbon emission during combustion. The traditional CH4production by fermentation presents the obvious disadvantages of low CH4yield (50–75%) and high CO2emission (25–50%). Herein, an efficient direct conversion of cellulose to CH4was investigated by using several hydrogenation catalysts. The Ru/C catalyst showed the excellent catalytic performance among all the studied catalysts. The optimized reaction parameters including temperature, time, pressure, and catalyst dosage were further investigated by using Ru/C catalyst, and the maximum CH4yield of 88.1% was obtained at mild reaction conditions (220 °C and 1 MPa initial H2). This value obtained is the highest yield for the production of CH4from cellulose to date. The reaction network suggests that the hydrolysis, hydrogenation, decarbonylation, retro-aldol reaction, and aqueous-phase-reforming are probably taking place, in which cellulose hydrolysis was proven to be the rate-determined step. This work provided an efficient approach to produce biomass derived CH4with extreme CO2emission (below 5%) and a better understanding of the cellulose hydrogenolysis process.

Sorbitol, as a C6 sugar related compound derived from cellulose, is regarded as a promising biomass‐derived substrate and has characteristically higher oxygen content than in fossil‐based resources. In this work, ruthenium–molybdenum carbon catalysts prepared by different impregnation processes were employed and extensively studied in a trickle‐bed reactor for sorbitol hydrodeoxygenation (HDO). Interestingly, these catalysts afforded remarkably different HDO performance. Ruthenium–molybdenum catalysts prepared by ultrasonic treatment and calcination obtained high HDO performance in sorbitol conversion with 79.8 % carbon yield of C5/C6 alkanes (pentane and hexane), almost twice that of ruthenium–molybdenum catalysts prepared without using a calcination processes. Therefore, a series of characterization studies (N2‐adsorption, XRD, HRTEM, XPS, H2‐TPR, CO‐TPD, NH3‐TPD, Py‐IR spectra, etc.) were performed over relevant catalysts to study the catalytic mechanism. The results suggest that prior calcination offers a better chance for the proximity between Ru and Mo precursors to produce the bimetallic catalytic structure Ru–MoOx, which produces high HDO performance. Sweet catalysis: Ru–MoOx/C catalysts from different impregnation processes were carefully studied and extensively employed for sorbitol conversion to C5/C6 alkanes in trickle‐bed reactor. The results suggest that prior calcination offers a better chance for the proximity between Ru and Mo precursors to produce the bimetallic catalytic structure Ru–MoOx, which produces high HDO performance towards biofuels synthesis.

Pharmaceutical synthesis keeps close ties with the development of heterogeneous catalysts; in this work, we report a facile way to prepare cobalt nanoparticles encapsulated by a graphene-shelled matrix, whose catalytic activity for a wide range of primary amines is proved to be broadly effective. As determined by its structural features, such a graphene-shelled matrix is characterized by surface defects such that inner metallic atoms are individually pulled outside by the divacancy sites; as a result, the delivery of metallic sites facilitates the easy substitution of the –NH2moiety toward functionalized and structurally diverse molecules by directly activating the C=O or C–N bonds in varied substrates, providing cost-effective access to numerous amines and other precursors for more complex drug products. In addition, the performance of this catalyst in a continuous test can reach at least 180 h without any loss of efficiency, which can be mainly ascribed to the protection of graphene-shelled structures.

One-pot achievement of ethyl levulinate from cassava was conducted in ethanol–water system over several simple sulfate salt catalysts. Al2(SO4)3catalyst had the best performance in synthesizing ethyl levulinate comparing with those of a series of sulfate salts. The highest yields of ethyl levulinate was up to 39.27% as well as 7.78% levulinate acid when cassava was catalyzed in ethanol medium by adding 10wt% water. 13C and 1H NMR spectroscopic investigations confirmed that isomerization of glucose to fructose over Al2(SO4)3catalyst is an important step in producing ethyl levulinate and levulinate acid. Due to aggregations of Al3+under hydrothermal conditions, tiny amount of Al3+were detected in filtrate at the percentage of 0.32% even if in absolute water. Brønsted and Lewis acids could improve the yield of ethyl levulinate and levulinate acid by synergistic effect. All results suggested that Al2(SO4)3was a simple and efficient catalyst for ethyl levulinate and levulinate acid production.

Metal–oxide interaction was widely observed in supported metal catalysts, playing a significant role in tuning the catalytic performance. Here, we reported that the interaction of Ru and MnOxwas able to facilitate the hydrodeoxygenation of levulinic acid (LA) to 2-butanol with a high turnover frequency (1.99 × 106h–1), turnover number (4411), and yield (98.8%). Moreover, this catalyst was capable of removing the hydroxymethyl group of lactones and diol with high yields of products. The high activity of the Ru–MnOxcatalyst was due to the strong Ru–MnOxinteraction, which facilitated reduction of Ru oxide to Ru0and Mn oxide to Mn2+. The increased fractions of Ru0and Mn2+provided metal and Lewis acid sites, respectively, and therefore facilitated LA hydrodeoxygenation. A linear correlation between the hydrodeoxygenation activity of the Ru–MnOxcatalyst and [Mn2+]ln([Ru0]) was observed.

Fe-based MOFs (Fe-MOFs) are deemed promising Fenton-like catalysts due to their well-developed pores and accessible active sites. However, their inferior catalytic activity, iron leaching, and low H2O2utilization always hinder their application as Fe-based MOF catalysts. In this work, we manipulated the structure of Fe-oxo nodes in MIL-88B(Fe) via a CuIspecies substitution method, affording a mixed-valence (Cu-incorporated Fe-MOFs) with highly improved Fenton-like performance. It is found that the CuIserves as a shuttle to promote transfer between FeII/FeIII, inducing the formation of a larger amount of stable FeIIsites, which was proven by experimental and DFT calculation results. A linear relationship was observed for the Fenton-like performance and the amount of CuIspecies for the catalysts. The corresponding value of the •OH formation is 2.17 eV for Cu-incorporated MIL-88B(Fe), which is significantly lower than that of MIL-88B(Fe) (2.69 eV). Meanwhile, the enriched CuIspecies suppress Fe species leaching during the catalytic reaction. The Fe-ion leakage of 0.4Cu@MIL-88B is very tiny (0.01–0.03 mg/L), significantly less than that of MIL-88B (2.00–3.02 mg/L). At the same time, H2O2utilization for 0.4Cu@ MIL-88B(Fe) is 88%, which is almost 4.4 times that of pure MIL-88B(Fe). This work provides insights into the rational design of Fe-MOFs as promising Fenton-like catalysts for wastewater treatment.

Direct CO2hydrogenation to value-added chemicals not only decreases carbon emissions but also provides an alternative way for fossil fuels. Even though some outstanding results were obtained, the high productivity of the target product is still hard to achieve. In this work, we fabricated a bifunctional catalyst comprising a Cu-modified Fe-based catalyst and ZSM-5 for selective CO2hydrogenation to aromatics with the help of XRD, H2-TPR, CO2-TPD, SEM, TEM and N2adsorption and desorption techniques for the catalytic mechanism of the prepared catalysts. The results show that the Cu promoter can improve the carbon-chain growth, suppress methane formation over the Fe-based catalyst, and then increase the aromatic selectivity over the bifunctional catalyst, suggesting that heavy olefin-based intermediates are more prone to aromatization than light intermediates. By lengthening the straight channel length of zeolites in the direction of the b-axis, a STYtolueneof 14.8 gCH2·kgcat–1·h–1is obtained. The relevant mechanism may be attributed to the increase in the b-axis length, which restricts the diffusion of products on the straight channel, forcing the product to diffuse from the sinusoidal channel in the ZSM-5 zeolite. This work provides insights for designing a bifunctional catalyst that achieves high productivity of high value-added aromatics.

In situ formed Ni catalyst combined with added solid acids is highly active for the hydrodeoxygenation of lignin-derived phenolic compounds. In the heterogeneous catalysts, in situ formed Ni acts as the hydrogenation and hydrogenolysis catalyst and solid acid acts as the dehydration catalyst.