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Sub-supercritical methanol and the phenol/quinone redox system were combined to promote the conversion of glucose to methyl glycolate.

The chemical transformation of carbon dioxide (CO2) not only reduces the amount of carbon dioxide emitted into the Earth’s atmosphere by humans, but also produces carbon compounds that can be used as precursors for chemical and fuel production. Herein, a selective catalytic conversion of carbon dioxide to methanol is achieved by a bifunctional molybdenum disulfide catalyst (MoS2) with magnesium oxide and nickel and potassium promoters. Molybdenum disulfide prepared by the supercritical ethanol method has a large specific surface area and presents good catalytic performance with high methanol selectivity when loaded with potassium (K) and nickel (Ni) promoters. In addition, the catalysts were evaluated and it was founded that the addition of the K-promoter improved methanol selectivity. This research provides a new strategy for improved product selectivity and space–time yield (STY) of methanol in CO2 hydrogenation.

In recent years, the application value of low-carbon alcohols (C1-C6 alcohols) in the fuel, chemical, environmental protection and other fields has become increasingly prominent. Catalytic conversion of synthesis gas to low-carbon alcohol is one of the important ways to realize the industrial production of low-carbon alcohol. Lack of high-performance catalysts is the main reason that restricts the industrial development of producing low-carbon alcohols from synthesis gas. The construction of a dual active-center catalyst with high activity and stability, and the study of its function and catalytic mechanism have become significantly important. In this paper, the characteristics of the reaction process of syngas to low-carbon alcohols, and the catalytic mechanism and preparation methods of different catalyst systems were reviewed, which provide the basis for further research on high performance catalysts.

Implementing coal to synthetic natural gas (SNG) is a key way to deal with the conflict between supply and demand of natural gas in China. For the coal to SNG process, gasification is a crucial unit, which determines the syngas composition and influences cost of coal to SNG system. In this current study, a coal to SNG system using ash agglomerating fluidized bed gasification is designed and modeled. According to the above results, the thermal performance and technoeconomic assessment of the coal to SNG system are performed. The research demonstrates that exergy efficiency and energy efficiency of the whole system are 55.37% and 61.50%, respectively. Additionally, the results of the economic evaluation show that the SNG production cost is 1.87 CNY/Nm3 with a coal price of 250 CNY/t and an electricity price of 0.65 CNY/kWh. Sensitivities to variables such as water price, electricity price, total equipment cost and coal price are performed. Coal price represents the most important sensitivity, but the sensitivity to water price is relatively small.

Most biomass derivatives were converted in the aqueous phase due to their high oxygen content, which, however, created a harsh environment for the catalytic reaction. In this work, Ru-based catalys...

Keto-alcohols, which are traditionally produced from fossil resources with multisteps, are considered as important intermediates for diversified high-value-added fine chemical synthesis due to thei...

Developing coal to hydrogen is a crucial way to alleviate the conflict between demand and supply of hydrogen. A coal to hydrogen process based on ash agglomerating fluidized bed (AFB) gasification is carried out and simulated in this paper. Life cycle primary fossil energy consumption (PFEC) and greenhouse gas (GHG) emissions analysis are carried out to provide theoretical guidance for the development of the coal to hydrogen process. Two scenarios, the coal to hydrogen process with CO2 capture and storage (CCS) and without CCS, are analyzed. The results show that the PFEC of the scenario with CCS is 2.32% higher than the corresponding value of the scenario without CCS, whereas the GHG emissions of the scenario with CCS are 81.72% lower than the corresponding value of the scenario without CCS. Additionally, the sensitivity analysis shows that life cycle PFEC and GHG emissions are sensitive to the hydrogen transport mode and hydrogen transport distance. Suggestions are also proposed for the development of the coal to hydrogen process based on AFB gasification.

Herein, a newly designed and synthesized fiber-supported polyquaterniums@Cu(I) served as efficient and recyclable polymer-supported copper complex catalysts for alkyne coupling and cycloaddition reactions, is reported. The fiber-supported copper complex catalyst was prepared systematically from commercially available polyacrylonitrile fiber, and characterized detailedly by elemental analysis, FTIR spectroscopy, mechanical properties, and SEM during both of the preparation and utilization processes. Moreover, the fiber-supported polyquaterniums@Cu(I) has been verified to possess high catalytic activities for the homocoupling of terminal alkyne in ethyl acetate (10 samples yields 83–99%, 10 cycles from 98% to 95%), A3 coupling of alkyne, aldehyde and amine in toluene (10 samples yields 81–94%, 10 cycles from 94% to 90%), and click chemistry of CuAAC reactions in water (10 samples yields 82–99%, 21 cycles from 97% to 96%). Furthermore, the newly developed fiber catalyst in spinning basket reactor displayed excellent stability and recyclability, and the concise and effective gram-scalable operation has extensive application prospect on chemical productions.

5-Hydroxymethylfurfural (HMF) which is derived from cellulosic biomass is an important platform for value added downstream chemicals and fuels via diversified processes. Nanoceria rods, cubes and octahedra were synthesized by a hydrothermal method and used as supports for preparing Au/CeO2 catalysts via deposition–precipitation. The morphology effect of CeO2 in the Au/CeO2 catalysts was investigated in selective oxidation of HMF to 2,5-furandicarboxylic acid (FDCA). The Au/CeO2-rod was more efficient for the oxidation of HMF and the TOF value of Au/CeO2-rod was 6.3 (min−1), which was 7 times as high as that of Au/CeO2-cube (0.9 min−1) and 32 times as high as that of Au/CeO2-oct (0.2 min−1). The experimental results and catalyst characterization implied that the oxygen vacancies on the Au–CeO2 interface determined the catalytic activity by affecting the size, and valence of Au and the interfacial acidic properties. The Au/CeO2-rod with the highest oxygen vacancies presented the higher proportion of cationic gold and more interfacial Lewis acidic sites between ceria and Au nanoparticles. Moreover, a synergistic effect between the interfacial Lewis acid, homogeneous base and neighboring Au particles promoted the oxidation reaction via efficiently activating the hydroxyl, aldehyde and molecular O2.

Using copper nitrate trihydrate as the copper source, TiO2@Cu-MOF nanocomposites were prepared by a one-step crystallization method, and the effect of the amount of TiO2 loaded on the adsorption of rhodamine B was studied. X-ray diffraction (XRD), scanning electron microscope (SEM), energy spectrometer (EDS), N2 adsorption-desorption (BET), and infrared spectroscopy (FTIR) were used to characterize the microstructure and surface properties of composite materials. The results show that the composite material not only has a good degradability for rhodamine B, the decolorization rate reaches 98.03% after 120 min, but it also maintains a good cycle performance. Fitting the first-order kinetic equation to the reaction process, under the optimal conditions, R2 = 0.98, indicating that the reaction process conforms to the first-order kinetic equation. Therefore, the catalyst has good catalytic degradation and cycle performance.

The bio-syngas formed from the catalytic cracking of bio-oil include two types of useful components which are light olefin and H 2 , CO. The integration of FTS and olefinic polymerization seems potential way for the production of hydrocarbon bio-fuels while fully utilizing the olefin-rich bio-syngas. This work aimed to develop an integrated process for the production of liquid hydrocarbons directly from the olefin-rich bio-syngas through a one-stage process, which included the synthesis of liquid hydrocarbons via the oligomerization of light olefin over HZSM-5 along with the FT (Fischer-Tropsch) synthesis of H 2 , CO over FeMn catalyst. A series of integration configuration composed of Fe-based catalyst (FeMn) and acidic zeolite (HZSM-5) were investigated, it was found that the undesired hydrogenation of lower olefin on the nearby metal active site seems greatly affected the yield of C5+ . More significantly, the proximity of the two active components plays a crucial role in suppressing the undesired hydrogenation reaction and contributing to the high selectivity of liquid hydrocarbons. The optimal catalytic performance yields a high selectivity to gasoline-range hydrocarbons (87.3%) with excellent low olefin hydrogenation selectivity (7.4%). Meanwhile, the obtained gasoline-range hydrocarbon showed high degree of isomerization. The integrated transformation process potentially provides an alternative way for the production of gasoline range isomerized hydrocarbon fuels using olefin-rich bio-syngas.

Herein, we report on a combined process that incorporates hydrothermal liquefaction (HTL) and supercritical water gasification (SCWG) to improve energy recovered from algal biomass. Eight algal biomasses, including four microalgae and four macroalgae with a large difference in biochemical compositions, were screened for this dual process. The algal biomass feedstocks significantly affected the carbon and energy distribution in the product fractions (crude bio-oil, solid, gas, and water-soluble products). 62.50–71.34% energy of microalgae and 6.03–41.06% energy of macroalgae could be recovered as crude bio-oil. 11.86–21.55% carbon of the microalgae and 8.01–15.82% carbon of the macroalgae was distributed in the HTL process water in form of water soluble products after the HTL process. 14.3–33.7% energy of microalgae and 30.18–36.34% energy of macroalgae was retained in the HTL process water. SCWG could convert the organics in the HTL process water into fuel gases consisting mainly of H2 and CH4. 54–91% carbon of the HTL process water was transformed into the fuel gases, which correspond 5.53–18.30% energy of the algal biomass. Thus, this work shows that the integration of HTL and SCWG could improve energy recovery from algal biomass relative to the HTL process alone.

Transformation of biomass wastes into sustainable low-cost carbon materials is now a topic of great interest. Here, a novel porous carbon has been prepared through activation of crab shell, which demonstrates an interconnected hierarchical porosity comprised of macro-, meso- and micro-pores as well with a high specific surface area of 1153.6 m2 g−1. Benefiting from the unique pore structure and oxygen and nitrogen dual doping, a well-developed ionic and electronic conductivity is achieved. Remarkably, when used as a anode material for sodium-ion batteries, it exhibits good cycling stability with a capacity up to 339.1 mA h g−1 at a current density of 0.03 A g−1, and maintains a capacity of 132.4 mA h g−1 even at a high current density of 0.5 A g−1 after 200 cycles, and still maintain high Coulomb efficiency. These results indicate that the fabricated porous carbon could be a promising electrode material for sodium-ion batteries.

The hydrodeoxygenation (HDO) of sorbitol in aqueous medium was performed over CNT supported Ru-Mo bimetallic catalyst. Compared with Ru-Mo/AC, Ru-Mo/CNT showed higher yield and selectivity towards C5/C6 alkanes due to the higher relative rate of C O vs. C C bond cleavage of sorbitol. Based on TEM, XPS and H 2 -TPR characterizations, the role of CNT in HDO reaction was studied to clarify the likely reasons for the selective C O vs. C C bond cleavage. It is suggested that an increase concentration of MoO x (x

Recently, we demonstrated the catalytic conversion of biomass hydrolysate and real biomass into renewable alkanes over a Ru/C catalyst with aqueous phosphoric acid (Ru/C+H3PO4) and we obtained a high yield of C5/C6 alkanes. In this study, the mechanism of sorbitol hydrodeoxygenation (HDO) into alkanes over the Ru/C+H3PO4 catalytic system was investigated by using a trickle-bed reactor. A high HDO performance was detected with a large amount of long-chain alkanes in the products. Subsequently, pre- and postcharacterization studies (N2 adsorption, XRD, X-ray photoelectron spectroscopy, TEM, NH3 temperature-programmed desorption, H2 temperature-programmed reduction, FTIR spectroscopy) were performed on the relevant catalysts to study the change of the catalytic active sites. Moreover, mineral acid experiments were performed to study the influence of phosphoric acid on the HDO performance.

Sorbitol was reported as one promising platform compounds as a C6 sugar related derivative from biomass cellulose due to its high oxygen content with six hydroxyl groups. Our previous work has reported the selective hydrodeoxyenation (HDO) of sorbitol into long alkanes such as pentane and hexane (C5/C6) over carbon supported ruthenium-molybdenum catalysts. Here, the effect of acidic pretreatments of those carbon catalysts on the performance of HDO reaction was studied in detailed. The result indicated that carbon support pretreated by phosphoric acid presented much phosphorus groups, but the carbon support pretreated by nitric acid presented high graphitization degree. Moreover, the phosphoric acid pretreated catalyst (RuMo/C–P) obtained high HDO performance in the sorbitol conversion with 79.7% carbon yield of C5/C6 alkane (pentane and hexane). Finally, detailed characterizations (N2-adsorption, XRD, HRTEM, XPS, XRF, Raman, NH3-TPD, Py-IR spectrums, etc.) were performed over relevant catalysts for correlating their catalytic and physicochemical properties.

In this work, a dual-bed aqueous catalysis system with Ru/C as catalyst was proposed for the liquid alkane (pentane/hexane: C5/C6) production from acid biomass hydrolysate. The low temperature (413 K) hydrogenation of biomass-derived carbohydrates into polyols was carried out in the first fixed-bed. The high temperature (523 K) hydrodeoxygenation (HDO) of polyols into alkanes was carried out in the down-stream bed. To screen the optimal reaction conditions, glucose and sorbitol were chosen for model tests. Whereby, reactor types, solution pH value, mineral acid, reaction temperature, pressure and sorbitol concentrations were studied. A maximum C5/C6 alkane yield of 61.9% was achieved from 20 wt% sorbitol solution (pH = 1.5) under 523 K and 4 MPa H 2 pressure in the fixed-bed reactor. For cassava and corncob hydrolysate, C5/C6 alkane yield of 38.8% and 44.1% were obtained, respectively.

Aromatics including benzenes, olefins and naphthalenes derived from renewable biomass are of great importance on the potential substitution for diminishing fossil fuels. In this work, aromatics from biomass-derived sorbitol by hydrogenation and aromatization was investigated over the Ni/HZSM-5 and Ni/Hβ catalysts in a fixed-bed reactor. The testing results showed that all the catalysts revealed 100% of sorbitol conversion, while the formation of aromatics and carbon species were various during the catalytic processing of sorbitol. The selectivity of aromatics was found to be 53.2% and 17.1% over the Ni/HZSM-5(38) and Ni/Hβ catalyst, respectively. In addition, the catalysts were characterized by N 2 physical adsorption, X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), H 2 temperature-programmed reduction (H 2 -TPR), and temperature-programmed desorption of ammonia (NH 3 -TPD) techniques. The characterization results revealed that the Ni/HZSM-5(38) catalyst contained the optimum acidic sites and the structural property, which favor the hydrogenation and aromatization of sorbitol in the reaction.

Coal direct chemical looping hydrogen generation (CDCLHG) is known as an attractive technique that converts coal into high purity H2 with inherent CO2 separation. In this paper, a CDCLHG system is developed and modeled. According to the prediction results, hydrogen element flow and economic performance of the CDCLHG system are researched. The study demonstrate that utilization efficiency of hydrogen element is 51.89%. By economic analysis, the results indicate that the calculated H2 producing cost of the CDCLHG system is 11.55 CNY/kg with coal price of 797 CNY/t and Fe based oxygen carrier price of 1986 CNY/t. Sensitivities to variables such as coal price, oxygen carrier price, water price and operating labor are researched. Coal price represents the most important sensitivity, while the sensitivity to water price and operating labor is relatively small. Additionally, H2 production from the CDCLHG process is only 3.0% more expensive than H2 production from natural gas chemical looping reforming with Fe based oxygen carrier. The CDCLHG process therefore appears to be an ideal option to obtain competitive hydrogen production.

Gasoline production by one-pot catalytic conversion of biomass derived sugar/polyol was investigated over bifunctional heterogeneous catalyst. Ni@HZSM-5/SG catalyst showed excellent performance of converting sugar/polyol to gasoline. The gasoline yield of 46.94% was obtained. Its composition and properties are similar to petroleum based gasoline. It provides a novel approach for the production of gasoline by one-pot aqueous phase catalytic conversion of sugar/polyol derived from biomass.

The activities of nickel supported on MCM-41 catalysts, prepared by co-impregnation with polyols (ethylene glycol, glycerol, xylitol, sorbitol and glucose), were investigated by hydro- genation of naphthalene. Compared with the conventional wetness impregnation, addition of moderate polyols into the metal nitrate aqueous solution could enhance interaction with support surface, resulting in formation of very small NiO particle size (

Exergy-based analysis is a powerful method to evaluate, understand, and improve energy conversion processes. Compared with conventional exergy analysis, advanced exergy analysis can identify the improvement potential of each component and the interactions among components of the whole system. In this paper, the ash agglomerating fluidized bed (AFB) gasification process is simulated in Aspen Plus (version 8.0). Based on the simulation results, advanced exergy analysis is carried out to study the performance of the AFB gasification process. The exergy efficiency of the AFB gasification process is 82.13% and the total exergy destruction is 4670 kW. The result shows that 54.18% of the total exergy destruction can be avoided. The AFB gasifier has the largest potential for reducing exergy destruction. In addition, sensitivity analysis is performed to research the effects of carbon conversion, pressure and temperature on the exergy destruction of the AFB gasifier.

Recently, it has been noticed that cyclopentanol, a versatile compound under heavy demand, could be alternative produced by hydrogenation rearrangement from biomass furfural. In this work, the design of synergistic ruthenium‑molybdenum bimetallic catalysts (RuMo/CNT) was firstly reported for the selective rearrangement of furfural to cyclopentanol in aqueous phase. Interestingly, the result clearly illustrated the significance of the catalyst reduction which tuned the metal/acid bifunctional roles and affected the catalytic performance. An unprecedented quantitative furfural conversion and high rearrangement selectivity (complete conversion, 74% selectivity to cyclopentanol, 9% selectivity to cyclopentanone) were achieved under the optimized condition over RuMo/CNT. Subsequently, detailed characterizations (N2-adsorption, XRD, HRTEM, XPS, H2-TPR, NH3-TPD, etc.) were performed over relevant catalysts for correlating their catalytic and physicochemical properties.

A series of MCM-41 supported Ni catalysts with high metal dispersion was successfully synthesized by simple co-impregnation using proper ethylene glycol (EG). The acquired Ni-based catalysts performed the outstanding hydrogenolysis activity of guaiacol. The effects of the synthesis parameters including drying temperature, calcination temperature, and metal loading on the physical properties of NiO nanoparticles were investigated through the use of X-ray diffraction (XRD). The drying temperature was found to significantly influence the particle sizes of NiO supported on MCM-41, but the calcination temperature and metal loading had less influence. Interestingly, the small particle size (≤3.3 nm) and the high dispersion of NiO particles were also obtained for co-impregnation on the mixed support (MCM-41:HZSM-5 = 1:1), similar to that on the single MCM-41 support, leading to excellent hydrogenation activity at low temperature. The guaiacol conversion could reach 97.9% at 150 °C, and the catalytic activity was comparative with that of noble metal catalysts. The hydrodeoxygenation (HDO) performance was also promoted by the introduction of acidic HZSM-5 zeolite and an 84.1% yield of cyclohexane at 240 °C was achieved. These findings demonstrate potential applications for the future in promoting and improving industrial catalyst performance.

Aromatics and cyclic-hydrocarbons are the significant components of jet fuel with high energy-density. However, conventional technologies for bio-fuel production cannot produce these products without further aromatization and isomerization. In this work, renewable liquid fuel with high content of aromatics and cyclic-hydrocarbons was obtained through aqueous catalytic conversion of biomass sorbitol over Ni-HZSM-5/SBA-15 catalyst. Texture characteristics of the catalyst were determined by physisorption of N2, which indicated its bimodal pore structures were microporous (HZSM-5, pore width: 0.56 nm) and mesoporous (SBA-15, pore width: 8 nm). The surface acidity included weak and strong acid sites, predominantly Lewis type, and was further confirmed by the NH3-TPD and Py-IR analysis. The catalytic performances were tested in a fixed-bed reactor under the conditions of 593 K, WHSV of 0.75 h−1, GHSV of 2500 h−1 and 4.0 MPa of hydrogen pressure, whereby oil yield of 40.4 wt. % with aromatics and cyclic-hydrocarbons content of 80.0% was obtained.