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The Al2O3-supported Ru-Co catalysts were modified by loading with several additives (Mn, Fe, and Cu) by incipient wetness impregnation and tested in the Fischer–Tropsch (FT) reaction using a simulated syngas (CO/H2) mixture similar to that obtained in biomass gasification (BG). The catalysts characterization included N2adsorption, X-ray diffraction (XRD), temperature programmed reduction (TPR), and scanning electron microscopy (SEM) techniques. The results show that the additives affected the catalyst activity and the C5+selectivity and Cu was the best species for improving the performance due to its excellent reduction performance and high dispersion of the active metal components. [ABSTRACT FROM AUTHOR]

Biomass resources are abundant in China, the cultivation of which is encouraged as it could provide energy for future social and economic development. Utilization of biomass pellets for energy through gasification could help ease critical problems such as energy shortage and environmental deterioration in China. In this paper, the performance of three types of gasification and pyrolysis reactors-downdraft, bubbling, and pyrolysis-were evaluated in terms of thermal output using the same corn stalk pellets. The three reactors were connected in parallel with a common control system, condenser, root blower, gas tank, and gas chromatography (GC) system. Gas composition was analysed using two GC columns. The lower heating values (LHVs) of the pellets, pellets charcoal, and bio-oil were analysed using a rapid screening device. Analyses of the properties of the pellets and pellets charcoal were carried out using an automatic proximate analyser. In the downdraft reactor, gas with an LHV of 3.91-4.44 MJ/Nm3 was obtained at a reduction zone temperature (RZT) of 660-760 °C. In the bubbling reactor, gas with an LHV of 8.48-9.38 MJ/Nm3 was obtained at an RZT of 575-750 °C. In the pyrolysis reactor, gas with an LHV of 14.51-16.49 MJ/Nm3 was obtained at a pyrolysis temperature of 380-530 °C, and pellets charcoal and bio-oil were formed in the pyrolysis reactor as gas-assisted products. [ABSTRACT FROM AUTHOR]

• CO 2 -gasification of PET waste for syngas recovery was investigated at 800–950 °C. • CO yields of 0.5–0.9 g were obtained per gram of PET waste gasified. • CO 2 utilization of 0.1–0.7 g were achieved per gram of PET waste gasified. • Char yields with BET surface area ~936 m2/g were achieved via gasification. Polyethylene terephthalate (PET) contributes to majority of the global plastics wastes generated and its lack of sustainable recycling calls for the development of pathways for this waste transformation to energy and chemicals extraction that will help avoid landfilling of this waste. In this paper, CO 2 assisted gasification of PET was investigated at 800 °C to 950 °C using a fixed bed reactor to understand the feasibility of this pathway for PET waste management. Evolutionary behavior of the yields of H 2 , CO, CH 4 , total C 2 -C 3 gases and total syngas from fixed bed reactor were investigated to understand the influence of temperature on isothermal conversion. Gasification composition and total accumulative syngas rate were also calculated and compared. Solid residues from gasification were analyzed for morphological characteristics and CO 2 consumption. Evolution rate and yield of H 2 , CO, CH 4 and total syngas from fixed bed reactor changed with increase in reaction time and temperature. CO yields increased from 0.5 to 0.9 g/g (gas mass yield per unit mass of PET), which accounted for 89.9 to 95.2 wt% of the total syngas yield with increase in temperature from 800 °C to 950 °C. The CO mole fraction accounted for about 73.3 to 79.4 vol% of their total syngas at the different temperatures examined. Brunauer-Emmett-Teller (BET) surface area of solid resides from CO 2 gasification increased from 434 to 936 m2/g with increase in temperature. These results showed thermal decomposition behavior under CO 2 gasification influenced the char structure and the effect became more pronounced with increase in temperature. CO 2 gasification of each mass unit of PET provided with the capability to convert about 0.1 to 0.7 mass unit of CO 2 into valuable syngas (a precursor for various value-added products) which reveals the synergistic possibility of PET waste management along with CO 2 utilization in this process of energy and value-added product recovery. [ABSTRACT FROM AUTHOR]

• Evolution of syngas and energy yield from pine bark gasification were examined. • CO 2 gasification yielded overall energy efficiency more than 55%. • Peak mole fraction of CO in accumulated product gas reached 19.3 to 46.8%. • 2.4 tons of CO 2 recycled per ton of pine bark gasified to syngas via gasification. Forestry residues, one of the main sources of carbon–neutral lignocellulosic biomass, are abundant to support energy sustainability and reduce carbon emissions into the atmosphere. In this paper, the characteristics of syngas from the gasification of pine bark in CO 2 atmosphere are presented using a fixed-bed reactor at temperatures of 700, 800, 900 and 1000 °C. Gasification behavior at these temperatures was investigated in terms of evolved flow rate of CO, H 2 , CH 4 , total hydrocarbons (C m H n) and total syngas yield. Solid residues were analyzed for morphological characteristics. Total accumulative syngas rate and overall energy efficiency at different temperatures were also calculated and compared. Results showed that gas yields of H 2 , CO, and total syngas increased with increase in temperature. However, the yield of C m H n was maximum at 800 °C. Syngas with heating value of 21.0 to 23.3 MJ/kg was obtained from CO 2 gasification. CO mole fraction accounted for approximately 66–80% (vol.) of the total syngas from char and CO 2 gasification via Boudouard reaction and hydrocarbon reforming with CO 2 at high temperatures. Gasification of each gram of pine-bark provided with the capability of converting ~0.25–1.74 g of CO 2 into valuable products examined at 800 to 1000 °C. The porosity and thus specific surface area of solid char residue increased with increase in temperature. Overall energy efficiency increased with increase in temperature to values as high as 56.6% at 1000 °C, while maintaining this high efficiency over long reaction times that revealed promising pathway for harnessing of energy production and CO 2 utilization. [ABSTRACT FROM AUTHOR]